Honestly man, your knowledge, presentation, and most importantly, your narration skills, are otherwordly. The latter is what keeps me glued to the screen and never notice when minutes fly by. I'm infatuated.
In terms of narration, apart from Brian Cox so far the only one who can convey the awe of science as succinctly. Really love the shit out of these videos!
Long form content that I watch multiple times to catch all the nuances. Man, don't ever change. You are one of the best things online, not to say on TH-cam. Thanks.
Your voice is perfect for this stuff, the cadence is unmatched and really emphasizes on peoples curiosity, and affects the ability of our attention spans to really get in and watch it all the way through. Thank you, keep up the great work.
He by whom you are so hypnotised, *Knows* nothing, because he cannot, because he is a *believer* - he simply cannot help it, has no choice but to believe, because that is what religion(defined as any set of related*Unquestioned* beliefs assumptions presumptions[and occasionally norms] or simply any set of related preconceptions) does, It simply preconceptions does to men (human beings/dreaming machines) it preconditions them to accept without question or believe or predicates or conditions the reason. Believers simply*Cannot* know(directly immediately personally experience)
@@richardmlouis Why are you like that? Maybe the little guy is happy because there are other people that are more aligned with his own thoughts and philosophies. We are humans and social animals. It's always nice to see like minded spirits.
Seriously TH-cam.. stop putting ads in mid-sentence. When it comes to science and lectures this is ridiculous it takes away from the content. Thank you Dr for another excellent experience.
TH-cam premium is actually worth it. Content is so much more enjoyable without ads and your video views support the content creator just as much as if you had sat through the ads.
Since TH-cam started making the advertisements more and more punitive, I consider it a moral imperative not to reward that with payments. Customers... Demand better.
Prof Kipping, I hope I can get to the point to be able to financially support the work you do, as the sheer amount of enrichment and education I’ve gotten out of your channel is immeasurable. Till then, thanks to everyone who can and does support, and thank you doctor kipping for continuing to bring us these amazing videos
@@justadildeau Haha. 50x might be an exaggeration. But yeah, David is fine. It is okay to donate though. Why not? David is a planet 'hunter' and trying to understand our surrounding. It is what I call consciousness. I need to be conscious. It gives my life meaning. If David can contribute to that consciousness, he's more than welcome. I think it is perfectly reasonable to support a guy like David that has more resources of achieving that goal.
@@justadildeau It is not a waste if you can afford it. And again, I agree, David doesn't really need it. He's fine. Stay safe bro and spend it wisely. Cheers!
Man I consider myself lucky to get to hear you talk. Thank you for the way you approach topics and your honesty while presenting facts. You are one of the best modern educators out there.
I'm glad you finally raised those caveats at the end: just how "earth-like" (this is likely a multi-dimensional "parameter") must a planet be for statistics like these to be calculable? Moreover, we can't exclude the possibility that some verrry different variety of life may arise & evolve in a similarly different environment. We can't begin to address these questions until we've surveyed a multitude of exoplanets in great detail. Or at least until we find microbes on Europa or Enceladus. At the other end of this, I agree with Steven Hawking that encountering an exo-civilization is dangerously inadvisable, as the likely disparity in level of development may mean that one will overwhelm (e.g., destroy) the other, or that the greater will regard the lesser much as we currently view colonial insects, or corals. 🦖? 🐒? 🦜? 🐠? 🐝? 🦂? 🦠? (?!)??
To me, the terrifying solution to the Fermi paradox is that life is common but so short that the chance of two civilizations noticing each other are infinitely small. We pop into existence that would be noticeable and disappear so quickly that anyone watching our solar system blinks and misses us.
Or... The rare earth hypothesis is true... And complex/intelligent life is extremely, extremely rare in the universe, because you need goldilocks conditions fore life to evolve to that point. Maybe Earth conditions are so extremely rare, that we are alone in our corner of universe. Despite life being so easy to thrive.
@@ianthor22 I’m afraid that solves nothing. If a civilization was broadcasting for 300 years, you still have 300 years to detect it when the waves pass by you. The fact that they travel forever does not help at all.
There are thousands of possible solutions. Coming up with solutions isn't the issue. The issue is proving them. This, just like every other possible solution, is totally inconsequential.
@@ianthor22 Our radio communications are only detectable at 1 ou 2 light-years away from Earth. If we were trying to actually send a signal to outer-space, that could change the numbers significantly. But at best we would be able to deliberatly send a detectable signal to a hundred light-years planet. By the way, our galaxy has a radius of 52 850 light years.
Complex life has had multiple hard resets through extinction events just in the past 600 million years. It's just not something that can ever be calculated or predicted in a sample size of one.
I tend to agree, but I am too lazy to definitively critique bayesian based statistical analysis; especially when applied to data points representing one instance.
If anything the fact that thea sample size is one tells you that life appearence from scratch it´s a rare event, because it never happened again (any new life appearence would have a different genetic code becasue there is no causal link between the codon and anticodon in the tRNA). We just don´t know how rare. I´m rusty on Poisson distribution but a once in 4,4 billon years should give a better estimate that guessing that life appears 200-700 millon years after it becomes possible
I enjoy the type of videos you make but what makes me come back everytime is how your passion can be felt through the screen and you always make complicated subjects so much easier to comprehend for an average joe like me. Keep it up!
This is the kind of content that got me hooked into studying Geosciences and also into Astrobiology. I cannot get enough of talking, thinking and in this case, listening to the passage of time that is just beyond human imagination. I find it incredibly tempting to think of former advanced civilizations that inhabited the Earth; its thrilling to think of their come back or maybe secrets they have deployed for future civilizations like us. Quite frankly, despite all the craze in the world right now, its mind-boggling, what humans are mentally capable of.
Professor Kipping, in the past especially your public lecture on the Cool Worlds Classroom Channel did a superb job in convincing me, it is likely we might be alone in the galaxy and even the universe. Like you said yourself: As the arguments in this video are only valid for an exact copy of Earth, this new discoveries about LUCA are interesting, but don't change much as we have still now idea how common "Earths" are. Thanks anyway for the entertaining and informative video!
Another thing. COMPLEX multicellular life only has about a 700 million year history. So much had to evolve, AND atmospheric O2 had to sufficiently increase to cause more bioenergetic pathways to evolve. In addition, what if a large meteor had NOT impacted Earth 66MYA? Would we be here now??
Need to be looking more into Earth's evolution, it's like looking for a needle in a haystack with no haystack until they know more about how life emerged here let alone anywhere else.
@@simoncove1 Possibly, though primate brains are legit just built different so probably not. Though we would certainly see non-avian dinos adapt to the glacial conditions of today’s Greenland and Antarctica, so that’d be cool to see
@@yancgc5098 small mammals did exist tho even back then so maybe anyway…. Might be inevitable give a planet like earth and long enough. Also yeah the continents allow ecological niches but yes let’s face it…. Who knows?!
LUCA is usually "last universal common ancestor". Lowest doesn't really make sense because lowest suggests the earliest, presumably somewhere back in the fuzzy weirdness of abiogenesis
LUCA means all life descend from this ancestor, it doesn't mean it's the first, just that this ancestor is the ancestor all modern life descend from. LUCA is not the first self-replicating molecule.
@@al-Assas Exactly, Lowest Common Ancestor (LCA) is a common term when discussing trees in computer science so given prof. Kipping likely had some exposure to cs/programming, it makes sense that he misspoke here. LCA is the last shared ancestor between two nodes in a tree. In this context, "last universal common ancestor" would therefore mean the same thing as "lowest common ancestor (on the tree of evolution)".
This is hands down, one of the best YT-channels ever made. This channel is so well needed in this ocean of drama, depressing news and jump cut attention span destroying content. :P
Saving this for bed. Thanks in advance for another thought-provoking video. Just finished watching this. I firmly believe that life started quickly but developed slowly. Things like the boring billion were necessary for the development of more complex life. A great channel for the evolution of life is The History Of Earth.
I will also point out that boring billion was also a break-point for life on earth. That is, it was either the stepping stone for more complex life or.. if plate tectonics had not started up again, it would have been the end of the habitable earth.
This is why it's usually best to resort to Bayesian inference to decide statistical probabilities. The human mind is not good at interpreting statistics and can easily fool itself. Then we have various cognitive biases to deal with.
Great example of appearing to be rational. It's not about time, it's about the conditions favoring certain breakthroughs, factors that do not fit a regular temporal lattice.
And even the intelligence of our n>1 is not quite sure... I will agree, when we stop destroing our habitat and learn to think and plan on longer timescales.
@@AndreasSmolka I just think it's a major reach to assume that 1. Life emerges from random stuff, since nobody's replicated this in a lab yet, so still n=1 there, and 2. Nobody knows how to define "intelligence" yet; it's all over the board. As soon as one person says it's cognition, language, civilization, etc., another says "yeah but chimps do all that." I don't think most scientists even take human intelligence very seriously. They were convinced by Carl Sagan and Frank Drake we needed aliens to help us get out of the Cold War; they were wrong, and they're still wrong
That’s a beautiful comment. I’m quite surprised that Prof. Kipping didn’t place more emphasis on this. Usually he comes across as the dilligent conservative scientist to me, and although he doesn’t actually say anything specific he changed his mind about here, and is very up front about all the "this COULD mean", "that MAY be", "what if" and so on, I find it to be quite out of character for him. In a disturbingly TH-camr-science’ish-clickbaity kind of way. Then again, that may just be how you have to play to promote actual science on social media.
Just think yourself lucky that you existed at all. Who's to say the people in a 1000 years time will be any happier than us. One presumes they'll have tech and knowledge far beyond what we can conceive but the human condition will remain the same.
There are numerous variables that could easily sway the conditions. From meteoric bombardment, to plate tectonics, star stability, solar flares, radiation, specific chemical ratio... And so forth. Then you have to have the right time frame as well. When taken all of those things into consideration, the number you get is miniscule.
a lot of emphasis - so much so that I did not understand a word - well, I understood what You said, but my brain did not process it due to the "backgrund noise" / the emotional charge - I was disrupted
I think the problem with the Fermi paradox is that interstellar travel is too big a barrier. We hear that events on Earth going back billions of years were such that life was nearly wiped out several times for various reasons. It is hard for me to see how one can use the time scale for how life evolved on Earth and apply it to other worlds with any expectation of being similar for another planet.
You wouldn't use that time scale though, you would go to the closet star which would take ~130-350 years will current tech (Orion Drive), then you would mine all the asteroids and debris around that star and use it to make a Dyson Swarm, maybe also mining the smaller moons and planets, then you launch ships to the closest nearby stars again, it would take a blink of an eye on geologic timescales to colonize the entire galaxy, doing so is theoretically possible with our current tech.
@@cy728 we can’t even colonize the moon after half a century after first landing on it. We can barely maintain a low earth orbit ISS and it costs an eye and a leg. Imo these speculations often ignore that what is theoretically possible is very different from what is economically and practically possible irl.
@@pansepot1490 u are correct for economic concerns can and has prevented advancement for decades now. Why switch to renewable resources when that ruins big fossil fuels profits? Why explore space when profits might not even be guaranteed in this life time? The reason it’s so easy to ignore economic concerns is cause unlike gravity or the vacuum of space, it isn’t a real problem to overcome, just one we’ve created for ourselves.
@@sleepninja2350 The implication here that renewables are "more advanced" is weird, because usually the person that favours renewables doesn't even make that case; they make the case that they're less polluting or something (and that's their entire case).
@@pansepot1490 The economics of space colonization change once you have a sufficient industrial base actually in space. We currently don't have a significant production capacity outside of our planet, so we have to haul all of our equipment quite expensively out of that pesky gravity well.
Another explanation for the early onset of life is panspermia. A smaller planet like Mars would presumably cool down and become habitable quicker.Even interstellar panspermia can not be completely ruled out yet. That could make single celled life reasonably common in the galaxy but still possibly extremely rare in other galaxies.
I'm betting on interstellar panspermia... bacteria ejected into the early universe from an older one. I am not convinced the age of our universe supports the challenge of evolving life in our simplest form unless it really is just anthropic principle explaining everything.
Ye great point, I was tempted to talk about that here but didn’t want the video to explode in length, I’ll definitely talk about this in a future vid 👍
Not necessarily. Bacteria cause infections, but have you ever heard of an archaean-caused disease? Archaea are extremely common yet the only health conditions associated with them tend to be imbalances in the already extant microbiome. Granted, archaea are more closely related to eukaryotes (and multicellular life) so maybe alien microbes would be pathogenic, but considering alien microbes would have nothing to do with our own biological processes then it would probably only be sheer coincidence if they're harmful.
Pathogens jumping hosts happens but between mammals. Anything more different just isn’t compatible. If the world doesn’t have multicellular life they aren’t adapted.
@@yannicmodritscher4646 True only for viruses. A bacterial form of life could adapt to more or less any environment with a supply of nutrients - e. g our bodies. It would then very likely produce chemicals toxic to us.
@@yannicmodritscher4646There are these recently unearthed mimiviruses that have allegedly caused upper respiratory infections, but they don't seem to be infectious.
A pathogen requires a larger, more complex host to infect - so there couldn't be a world inhabited only by pathogens. There may be lots of worlds, however, where life never gets beyond the level of the single cell.
I know it sounds bad becuz it’s sounds like I only watch to hear what I want, but it’s nice to hear you more positive on the likelihood of life. That is because I respect your intellect so much
Short answer: very, very far away. I find it stunning that few people tend to grasp the implication that the vastness of space brings. Even if one assumes there are a million civilizations roughly equivalent to ours (at our stage of development) spread throughout the universe, the distances involved makes contact highly improbable, if not completely impossible at any stage.
@@siubhan2047 some communicative discord could be possible , we can't for see tomorrows tech , same goes for traversing the galaxy , physics is ongoing we nowhere near answering or discovering everything
I have to confess that I'm not sure I accept that life occurring very early necessarily implies that it's likely to occur. Certainly if there were many planets like ours, and life always tended to occur early, that would be compelling. But with exactly one data point, it seems like "maybe it just happened to occur early here - regardless of the odds of life occurring". Am I missing something?
OK - I went back and reviewed it. I feel at least a little less silly now. I think we're talking about different things. You're describing the rare Earth hypothesis - which is certainly a valid consideration. Not only may it be important to have a planet extremely similar to our own, but perhaps it also has to go through some of the same changes as Earth. What I'm asking is a different question. Perhaps abiogenesis would be a very common thing under perfectly ideal conditions. But perhaps not. It could be an astonishingly improbable event even under the best circumstances. I think the notion that it occurred early on Earth is used to "prove" that it's a very likely event under the right conditions. But I'm not sure we can make that leap based on a single case. Perhaps it's an incredibly unlikely event that simply happened to occur quite early. If I'm right, we would only be able to know this if we saw how quickly it occurred on many ideal planets.
@@Rick_Cavallaro The thing is, because we have only one sample (earth) its logically more probable that we are the norm as opposed to the exception. Therefore we can extrapolate based off that as this video does, but if we are the exception (as your suggesting) then the math changes.
@@user-ga5fne3h I'm not suggesting that we're the exception, I'm only asking whether a single data point can tell us anything at all about the probability that abiogenesis is a likely event under the best of circumstances. I admit that the fact it seems to have occurred almost as early as possible in the one case we're aware of would make us inclined to believe it's a highly likely event, but I don't know if the math bears that out. >> because we have only one sample (earth) its logically more probable that we are the norm as opposed to the exception. I also don't see how that follows with only one data point.
Hey Cool Worlds changing his mind? This is why I remained subscribed to you. I disagree with your conjecture on certain topics, but I respect you as an academic and I am absolutely happy to hear someone as highly educated as you changing your stance on the odds of life.
I really love your channel. You’re clearly very intelligent and educated. Yet you still have an open mind for the potential future of science and its discoveries. I’ve met many highly educated and intelligent people who are completely unwilling to bend any beliefs on science or otherwise. You are an inspiration. Keep doing the fantastic work you do.
I’ll take the in between. We won’t see them in 100 years, but not cause they’re not there but because they’re so advanced they can keep earth in essentially a nature reserve forbidden from the public.
I don't think it's likely that we will ever receive a signal from aliens because im assuming they would only send signals to stars where they can observe planets using the transit method and the chances that they are at the precise angle to even make that possible seems very unlikely also since they could be so far away i don't think they could predict where our star will be in the future for them to even aim the signal at due to random variables
I am not of a sciency background but love astronomy and astrobiology and sciency things..I really found myself not understanding the technicalities of the video (frustratlng) but watched and tried to grasp as much as possible..thats the sign of a good teacher, to inspire..this is indeed exciting stuff!
It helps to check out the cool worlds videos. The ones from 5 years back are great and help to give a better context to his current videos. This video especially depends on watching all of his videos addressing the Fermi Paradox and the duration of life on our planet. Most of them require very little math beyond simple logical analysis and graphing comprehension.
Please, continue thru Cool Worlds to make lots and lots of podcasts! Kindly allow me to echo the immediately foregoing comment, "Honestly man, your knowledge, presentation, and most importantly, your narration skills, are otherworldly. The later is what keeps me gluded to the screen and never notice when minutes fly by. I'm infatuated."
If life gets going relatively easy, an inevitability of some kind of assembly/ information theory, then why is all life descended from LUCA? And why can we not find any life precursors anywhere on earth? If life were easy, shouldn’t there be signs/ evidence of new life attempting to create itself all the time that we can detect?
Well, it's not as easy as that. Life could have started easily in the conditions on the young Earth, but conditions have changed, and life might arise with more difficulty now. Second problem would be that new life appearing would be an easy prey for established life forms like predators. In many online build-and-wage-war games, time-in is a good predictor for your success. The same will generally hold for life. It's like a pyramid game really.
@@TicTac2 You forget that many animals eat plastic, mistaking it for food. And left-handed sugars can be eaten by certain pathogenic bacteria. Take it easy. Remember that only a vanishingly small number of organisms that ever existed, "live on" in the form of fossils, and we will find only a few of them, because many are buried deep inside the rocks or they have been destroyed by metamorphosis or erosion. Many attempts to start life could have failed very quickly, either by being eaten or by being at the wrong place at the wrong time. But once it is there to stay, it will have to compete with the already existing life. And for all we know, some life forms that now exist, with different DNA encoding, might well be the result of a separate origin, if the RNA DNA path is inevitable on the road to life.
There's a big big big difference between a civilization and "life". The odds of life and the odds of a civilization should never come close to being mixed in any way shape or form. It'd be like mixing the odds of ever having a date in your life VS the odds of sleeping with super models your whole life, becoming a rock star, and super rich. The Huge part is going from mere single celled organisms to multicellular organisms and making that leap. And life existing on this planet will last longer than 900 million years (assuming no planetary collision or change of orbit toward the sun). Life at the bottom of the ocean is one example of this, and I never heard of people believing No Life would. That's why it's a problem equating life with advanced beings that's on a totally totally different plane.
Very underrated comment. Too often I see astrophysicists talking as if civilisation is _on average_ a necessary consequence of life on a planet, and drawing statistical conclusions from this assumption. If we look at palaeoanthropology, we see that even intelligence (Homo sapiens and our close cousins) is not guaranteed to develop civilisation (agriculture, cities, metalworking), let alone a technological one like ours. The time from the emergence of our species in West Africa to the Neolithic Revolution is 95% of our evolutionary history, and we could've gone completely extinct several times during that interval. Which intelligent species would have taken up the mantle of civilisation? And when? Add to that the fact that space travel is probably unfeasible (unless we're missing something big in our physical laws, all we can do is send out probes that will _maybe_ reach their destination in a few millennia and _maybe_ report back to a civilisation as far removed from us as we are from the ancient Egyptians... Why should we do such a thing?) and we can see that Fermi's question isn't at all difficult to answer.
My biggest issue is your time frame. It's all based on OUR solar system. There are trillions of solar systems over billions of years. There are untold numbers of solar systems that have been around for 10 billion years. 700 million years (based on one case study) doesn't seem that long. Great episode.
Ohh that's a great angle. Makes sense. The variety of conditions is immense. As soon as that big new ESA telescope start running and gathers the exo planets data we can start adjusting these theoretical boundaries
Well, if you would have watched any of his previous vids. That was EXACTLY his argument. I tend to disagree, because it's fact. We exist and therefor it is evidence. Sure it is one example, only but it is all we got. So, I'm going to draw conclusions from that one example.
As human, I get humbled in front of the universe and it's grandness. As a vlogger, I get humbled in front of Cool Worlds and it's majestic content. Thank you David.
IMO: any reference to Earth is (largely) irrelevant. All that really matters is if there are other planets with the key features needed for life to start in the first place. We simply can't answer the likelihood of such via reference to Earth.
13:30 surely in 900 million years from now we would just convert whatever was needed into CO2 and pump it into the atmosphere to maintain what ever biosphere is left at that point in time, therefore, extending the habitable period?
Or just move the Earth out a bit. Move a big asteroid to fly by the Earth at regular intervals and drag the Earth out. I'm sure we'll be able to that in a 1000 years, much less 1 million.
@@AlexRussell-kd9pd 10 m per year, over billion years, 10,000,000 km, sufficient to cool the planet. Wouldn't try such an orbital movement in 1000 years, too much risk of earth quakes.
Three thoughts: 1) Evolution rate is quite variable. The coelacanth, sharks, and alligators are all examples of life that have changed very little of hundreds of millions of year. Human could considered the fastest evolution rate since we have clearly definited intelligence yet have not beeen around very long (relatively speaking). The real trick of there being other intelligent, and even space faring, races is what factors sped human evolution and what would the maximum for those factors be? Even on a planet with a shorter life span or less ideal conditions an intelligent race could evolve if the evolution factors were strong enough for force it without reaching extinction levels of stress. 2) Planetary life span is only being calculated based in non-interferrence. If a species becomes intelligent enough and aware of issue affecting the planatary life span, they could take actions to reverse or slow down the dying process, gving them time to evolve and advance more. 3) Even if life on the surface of a planet becomes overly stressful, it could move underground and still develop to become intellgent and spacefaring. Basically, life finds a way.
I know that i might sound like a jerk, but your arguments would be more compelling and logically rigorous (against critics and trolls) if the phrasing of your essay was proofread and corrected. For me, proofreading also helps to identify arguments or statements that are heavily based on my emotional state or personal bias. I am trying to be a friend with the previous statement. Addressing your statement: You make three compelling arguments that seem to make the case that the life-span of our planet is very different than the one Professor Kipping has stated. Your first statement may be correct; however the difference in time for rapid evolution versus the typical duration is small in comparison to the eons that measure the duration of our planet. But, data and scientific analysis could easily prove me wrong. I agree with the second and third points. On the second point, it seems obvious that if we can easily imagine ways to: move our planet; 'terraform' other planets and even adapt our species and intelligent machines to thrive in hostile conditions then the life-span of our planet and star will be extended. Our effective life span would then be indefinite. The survival of humans and our descendant species or machine intelligences would then only depend on the total amount of usable energy and materials available in our Solar System or nearby star systems. On the third point: microcellular life on our own planet has penetrated miles into the crust of the Earth according to scientific reports. Even after our entire planet was covered with miles of ice from pole to pole for thousands of years life re-emerged. This happened at least twice according to geologists. Multicellular life emerged and continued to evolve into the diverse forms of life today. We might be lucky among the few planets with emergent life or typically resilient survivors as you imply in your essay.
You have an excellent point. If you look at all the life forms you realize intelligence at our level is very rare AND not necessarily a good survival trait since saber tooth tigers can easily gobble us up. Another point is if intelligence evolved in sea life, like the octopus. No fire, no quite a lot.
I think you have a mistaken idea that evolution has the goal of higher intelligence. Natural selection is about reproduction. Therefore, an evolution rate would quantity a species ability to adapt. Humans are actually quite slow, especially compared microbes. It takes over a decade for us to be able to reproduce and we don't have a lot of offspring compared to other species. That's a major reason why infectious diseases are so hard to fight. Microbes can adapt in days. Humans are far far slower.
@@marveloussoftware4914 Except that intelligence allowed us to out avoid them, out smart them, and finally out live them. Sure one on one they have the better chance of winning, but smarts ultimately won.
@@someguy999 No natural selection is about survival of the fittest. And fittest is a variable concept since it all about surviving the natural evvironment that you happen to be in. And the natural environment changes based on a number of factors like seasons, location, and natural hazzards. Being inteligent help to give one the greatest chance of surviving by being able to make tools to enable survival without necessairly evolving claws, hooves, altered eyesight, and such which would take very long time to develop. Intelligence is the ultimate Swiss Army Knife as long as it's properly applied. It's true in some cases it's has its limits based on the available resources, but generally it's the best survival tool, along with knowledge which is something most animals don't really possess. Having a mind that can learn, hold knowledge, and pass it on to the next generation ultimaltely leads to intelligence and higher survival rate.
Ah, the joy of learning something new that changes your outlook on something! I grew up with learning about 3 states of matter and three allotropes of carbon and sunlight was required for life to exist - and am utterly delighted that we know better than that, now. Likewise, it's wonderful to hear that recent studies and discoveries indicate a higher likelihood of life starting easily than we previously thought.
I don't understand why most people are so dubious that life is common when we literally live in a big pit of life that randomly cropped up. It's all around you and in literally every place we look, in poisonous vents, in volcanoes etc. The occam's razor on this topic quite obviously slices on the "life is common" side.
@ Yeah lately I've been realizing that everything really is that stupid. Everyone. Every person ive met. All of it is based on this weird idea that humans are special. Depressing shit.
It’s also unlikely that the first time single cell life got started in Earth, that it survived. Life would have started multiple times before something took hold. Then multicellular organisms, did the first one of those survive or did it die? Again, probably the first one died before it could successfully evolve and take over.
@@ksh95If you knew almost nothing of the universe this assumption should be pretty logical to make. It shouldn't have blown out minds when learning it is a fact
As a biochemist with an interest in the origins of life I do not particularly care if life elsewhere achieved a 'technological civilization' state, but rather on the origin of what we call life, and in understanding what life is. I would issue a challenge that we can ask biologists and biochemists and most will not be able to produce a description of what life is that is truly universal, and not just relevant to terrestrial life. If the microfossil record is correct, i.e. it really represents structures that were 'alive' 3.7 billion years ago I would completely agree that life is not fussy. How long evolution takes, and the paths that it ends up in are irrelevant. It is only important for us humans from an antropocentric perspective, where we want some life, somewhere in the universe, to converge on a technological civilization, but as a biochemist that criterium is really not relevant. Having said that, I think that as life's complexity increases also its frequency decreases. As a system that is in a continuous state of non-equilibrium thermodynamically, it will also require conditions that must be stable over an extended period. The higher the complexity the narrower the range of fluctuation of environmental parameters that are compatible with that complex life. Sure evolution will enable change, but evolution also working on a species and not individual level, it will also require long periods of time of stability.
That's a great point. If we consider our own impact on our environment right now, our chances of lasting 900 million more years at this rate are slimmer than the Planck length on a vegan diet. I take it you're familiar with Jeremy England's 2014 paper on the emergence of life as a highly efficient distributor of heat? I quite like that hypothesis.
It's not merely because we're chauvinistic about technological civilization that we look for it amongst the stars. It's more the fact that we ourselves ARE a technological civilization. If we hear nothing, if technological civilization is fleeting enough that it is undetectable on cosmic scales, what does that say about our future?
@@Stadsjaap - I strongly doubt any one complex life could reasonably be said to last 900 million years as numerous extinction events seem to prove but there always seems to be another to take up the batton
@@sja45uk I completely agree. The extinction events in Earth's past completely remodeled the biosphere as a consequence. In the absence of those, Earth's life makeup would be very different. As to life's origin, and life in general, biochemically I see it as a series of events (chemical reactions or physical changes) that as a result of a continuous energy flux tend to optimize the thermodynamic exchanges with the surrounding environment. Jeremy England is one of the latest in a line of physicochemical scientists who have been looking at this problem as such (Ilia Prygogine being one who in the 50s and 60s) started looking at dissipative structures and non-equilibrium thermodynamics). That is how I see life, from a biochemical perspective). Yes, there is much we do not know, but I think some of the researchers are on the right path. But it is something that we will never know for sure, how it originated on Earth. The best we can hope is understanding its principles and perhaps reproduce it (microscopic) in controlled conditions.
Do you have a working or provisional definition of complexity? It's often mentioned but rarely defined. Genome size doesn't work, as I doubt that anyone would consider an onion to be more complex than humans. The number of proteins doesn't work ("simple" worms like C. Elegans have similar numbers of proteins as us). Maybe the number of organs or tissues could work, but I haven't given it much thought...
You could have done the math for lower mass G type stars. Theyre similar enough to our sun, but can last upt o 30% longer giving intelligent life more time to evolve.
@@TheDotBot Yes, the sun is unusually, extremely quiet. How much this actually matters is uncertain, I think it is important. Everything about our solar system that is unusual should be considered important until proven otherwise. Personally, I think this is because the sun's mass is perfectly balanced between the CNO and proton-proton chain methods of fusion, and this acts to stabilize it. (Lighter stars only do proton-proton and heavier ones do mostly CNO, but the sun does both). But I'm not an astrophysicist, so I could easily be wrong.
@@fluffysheap Interesting, as I understand it, the sun's quiescence compared to other G-stars is (largely) due to its slow spin at the equator and low magnetic field strengths, and that CNO cycles being a threshold thing would affect the sun's overall output stability but not surface activity, which is tens to hundreds of thousands of years away from the fusion reaction in the core. Same disclaimer, I'm not an astrophysicist, so anything I say could be stuff I've picked up and completely misunderstood, or it could be obsolete knowledge or whatever, and I'd be more than happy to be corrected.
Hypothetically if the Europa clipper or another project discovers independent simple life but we don't have an estimate for when that life started, how would that impact the model?
They will going to make a new copium stuff because they still want earth/our solar system be special, but the thing is, more likely life/intelligent life is everywhere, like in Three body problem
This model is just for earth-equivalent systems so it wouldn't impact but it means the universe is surely teaming with at least simple life. Honestly the problem I have with extrapolating this model out to the whole galaxy is we still have yet to even find an earth like exoplanet.
5:00 2 Things: 1) We aren't looking for intelligent life, just life. So a planet could be anywhere in the 3.7 bya-to-today time span and we could find life (based on prior assumptions). 2) Our evolution was catastrophically altered by the asteroid that killed the dinos. Thats a pretty low odds event that severly slowed us down.
One problem with this is that we really lack a genuinely operational definition of what life is. For instance, viruses are studied by biologists, and seen to be specifically linked to life as we vaguely understand it. As concerns CO2, there are several discussions that indicate that primary production - conversion of water and CO2 into carbohydrates - essentially stops between 200 ppm and 150 ppm. In addition, empirical data also shows that prmiary production is already limited to some degree by _low_ levels of CO2. This is shown by the positive response of desert margins to increased CO2 since around 1950.
4:48 The weak anthropic principle wouldn't state that the existence of simple forms of life or intelligent life found here on earth proves that the process is easy. It simply states that the existence of life here proves that it is unremarkable. The WAP is a perspective about the existence of life's remarkability. It is an antithesis to creationism, or the strong anthropic principle, the WAP stating that SAP's analysis is based on a selection bias, i.e. where else would there be intelligent life to reflect on the remarkability of its existence than the place where it happened. Anyway, to my original point, the WAP would state that even if earth is the only planet in the universe with life on it, that is still proof that it is unremarkable
@@daMillenialTrucker Would we be having this conversation if life evolved in the center of a star? Or on an asteroid floating in deep space between galaxies? Nope, because it's extremely unlikely to be possible there. How nuts is it that life occurred on a planet where the conditions are favorable, in the goldilocks zone. On a planet with this much water. With a sufficient magnetic field to protect from cosmic rays and solar ejecta. With a gas gas giant stabilizing the asteroid belt to slow accretion to the degree Jupiter has. It's not nuts at all. You and I are living in the place where that happened.
@@skengasaurus did you know they even found water under the crust of the earth? It's literally 400 miles below earths crust lol WHAT IS EVEN GOING ON!!! 😂😂😂😂
My argument is still that the problem with the Fermi Paradox isn't how common life is, but how can we detect it? If our best means of detecting exoplanets and exomoons is watching for a dip in luminosity in its star, how exactly are we going to figure out that life exists there? If a planet is 200 million light years away and evolved life 100 million years ago, how could we possibly ever detect it? Yeah, we look for radio signals, but how do we know aliens would even use radio, or communicate via sound in the first place? What if aliens evolved a system of visual or written communication only? What if they communicate via chemical signals, like many microbes do on Earth? That's really my problem with all of these equations, we are operating on the assumption that intelligent alien life would look something like us, but there could be any number of hidden variables changing things. I simply can't accept that Earth is the most unique planet in the entire universe, that sounds like hubris to me. The probability that life does exist but we don't currently have the technology required to detect it seems much higher to me. Call that wishful thinking if you want.
To be fair, as David has pointed out many times, there really are two variants of the Fermi Paradox. What he calls the "weak" Fermi paradox is why we haven't observed aliens. What he calls the "strong" Fermi paradox is why aliens aren't here among us right now. That is also the variant that Fermi himself was originally referring to. Why the Earth isn't an alien colony. There has been plenty of time for expansionist aliens to colonize the entire galaxy, and it seems very unlikely we wouldn't be aware of it if Earth was currently an alien colony.
There are a range of chemicals not produced naturally that we could snoop in an Exo Atmo. That's strong evidence for intelligent life. But I agree with you. There are hundreds of different amino acids yet all life uses the same 21. What if life evolved using a different suite? It might turn out radically different.
That last sentence you wrote about the probability seeming higher to you is a fallacy though, that’s just a total guess that feels more right to you, but has no mathematical backing
I think we would notice if aliens had colonized Earth and were living here. We would also notice if aliens had started building Dyson swarms around all the stars, or were tearing them apart for materials. In fact we probably wouldn't exist in both scenarios. That is the Fermi paradox. There has to be a rate of life. There is no reason that number can't be incredibly small. Like one in a trillion, or one in a trillion trillion. The fact life exists on Earth gives us 0 information. If life didn't exist here, we wouldn't be here to observe it.
@@CoolWorldsLab - I can't think of any reason why a sterilising impact would be necessary. Indeed if life was not present then I don't see what sterilisation means!
@@sja45uk I will posit that i am a creationist so it's not my forte (yeah i know, creationist in a evolution topic), but one of the major ideas for how life could have been sparked seems to usually require intense heat events, a lightining strike, volcanic vents etc, there's no reason to think a impact event wouldn't be able to do that as well, especially if there are ways for elements to form we haven't discovered yet, for example, earth is a rare planet with phosphorus, there's no guarantee that phosphorus or some other element could form under the rare conditions of a sterilization event impact, as it's unlikely we'll be able to even test those conditions for a long time what would happen in such of a event is only something we can make educated guesses on..
Great video. But isn't there still one factor you haven't addressed that could kill the theory? Namely, the likelihood of abiogensis. It is entirely possible that abiogensis is so incredibly unlikely that it literally never happens, except here on earth. And since we don't even know, really, anything about abiogenesis, we cannot possibly discuss its likelihood. The only stance we can take is one of utter agnosticism.
I think it is a fair point that 72 years after the Miller-Urey experiments chemists still don't have a plausible model for abiogenesis. If it is easy someone ought to be able to replicate it.
I think what you've done is just rule out life around F type stars, which we kind of suspected anyway. But you also don't rule in K type stars which give around 10 times more time than G types. Also one of the great filters would be Eukaryotic life. It may be that 3bn years of Prokaryotic life could be anything from at the earliest, an average or a latest event before the first Eukaryote.
Another assumption is that evolution would typically take so long before sparking into complexity. What if some environments push evolution hard so it has to adapt a lot and often? Between the two assumptions and the sheer number of chances out there, I think life, even intelligence, might still be common enough. I did find his point on the window that life has to do these things very eye opening when I first ran across it, and while his point does lean on our experience alone since that's all we have, it could be valid enough to reduce many chances across the galaxy.
It's hard to get passed the weak anthropic effect, where the odds of life occurring on a planet where the occupants want to know what the odds are, is 100%. This is interesting and thoughtful work, ideas rather than facts though.
Thank you for explaining things like this in an easy to understand way. Your video are always informative but this one kind of blew my mind. Thank for presenting it in a way that that I can understand it.
I sincerely hope so too. If there's 'anything' that seems 'living' would indeed *change everything.* My gosh, what a tremendous finding. But then again if not, that's fine. It pushes back the hope of finding something back a bit. I really appreciate his approach to this subject. He holds reservations about finding something as if, it's gonna happen every time and every place. I'm in the same camp. Looking close into the actual mechanics that would enable life to start. All very fascinating to me.
I hope it does not. I would love it if there is life on other planets, but it would be best for us if there is no life in the solar system even a basic one. That way we will be able to expand and use the resources of the solar system to prolong life on Earth, including sentient intelligent life. Clearly, we could be gravy Aliens and just go to Europe and exploit the water and use the same reasoning used for abortion (even better because it won't be a clump of cells) but it will be divisive. Also as the activity of the Sun increases we may need to move.
Note that Stromatolites are fairly advanced lifeforms that have developed the ability to glue themselves in place and have everything they need for survival delivered to them.
Prof. Kipping, if indeed we have about 900 mil years left, surely there's enough time for you to make a video/podcast about Quasars and Magnetars, right? 🙃
I do not think there is enough negative bias being applied to our thinking, regards the exacting balance required for evolutionary presure, to much pressure and evolution fails, to little pressure and it fails...that sort of puts the odds against evolved life in the universe up a considerable amount.
The early collision hypothesis is the only way we come up with a large moon like we have. The likelihood of a Planet having a moon as large as ours is extremely unlikely for many reasons.
@@altus3278 The likelihood of a planet having a moon as large as ours is 100% *given we've seen it in reality*. Bayesian statistics gets you like that.
@@georgespalding7640 pretty sure, the moon also has like a similar composition to "earth rock" aswell almost like it's a chunk of the planet that consolidated.
You have to also remember that life on Earth had some setbacks that, while common, aren't necessarily ubiquitous. We can likely assume a nonzero number of atmospheric changes similar to Earth's oxygenation event, which caused mass extinction; but things like asteroids and other natural disasters are all up to chance.
I think that's an important point - For example, the Earth was in an evolutionary stall for about a billion years. How does that affect the numbers? Also, there have been several extinction events, how many of those were outliers? All of them? None of them? We only have one example. So timelines and some clever analysis gives us very little idea of how common life is in the universe - apart from the basic fact that some kind of life started fairly soon after it could.
Aerospace Engineer here: In the last couple of years I have gotten into economics for the simple reason that economists are interfering in engineering to a staggering level, which is why we have an energy crisis, but that's another story. In looking into another profession and how it trains people you not only get to examine that profession but re-examine your own and we don't do that enough. One of the great flaws in economics is the lack of self-evaluation. They have an awful lot of theory and modelling that has NEVER been truly tested except on US and right now that's looking like very bad outcomes as they keep telling us all is well and that's not going to end well for any of us. Your profession is in a similar predicament except you are NOT costing several billion people a future like economists are. HOWEVER, what you and you colleagues are doing is modelling based on UNTESTED THEORY. Yes this is all very interesting and I like your channel because it expands my own knowledge base, but you need to temper this will reality and let people know these are theories that are UNTESTABLE because of the time frames involved. They are some every interesting theories and models but they are just that - theories and models. *PLUS* and I can't emphasise this enough with dating technologies whether its carbon dating or any other dating. CALIBRATING your measurement system is almost impossible beyond a few 1,000 years because where's the actual sample that you know for certain what its age is that you can use to calibrate against. Your calibration for longer time periods is theory not measured reality. *You are one of the very few sciences that is allowed to get away with this lack of calibration but then we also understand that calibrating such systems is almost impossible.* So you get some slack on this, but please DO NOT MISTAKE that other STEM fields are unaware of this.
Radio active decay is quite a well studied process and we don't expect it to disobey the established models of nuclear science. Decay models are derived from Quantum mechanics which is one of our most precisely tested theories.....what is the objection here?
@@kanishkchaturvedi1745 *I KNOW THAT* And if you bothered to READ what I have said that is the problem. Do you know that when they carbon dated the Shroud of Turin they used the 3 best labs they available and the results varied by 10% at 1,000 years age. If radioactive dating is so damn accurate and so well understood then how do 3 top labs have that much variation? ALL measuring techniques have limits to their accuracy which is why calibration is so incredibly important to understand. Metrology (the science of measuring) is one of the least understood fields of science and yet its one of the most important. But trying to explain that to IGN0RANT M0R0NS is hard.
How do we know that life that developed here wasn't just a 'slow starter', and other intelligent life hasn't/hadn't developed MUCH faster than we did here on earth?
What I never understand is; If we all have one common ancestor, such has been proven. Then this means life has only begun once in 4.5 billion years. Evidently making it extremely rare! Surely answering the Fermi paradox.
We have two - at some point mitochondria were taken into single cells as a symbiotic relationship, although the details are still debated on. If we had two at one point, there could have been more that simply didn't survive later changes. Once life became prevalent its activities would make further chemical replicators nearly impossible due to competition. Life on a blank canvas may start early and often. We only have one example so far to work with.
There was an emergence of life on earth before us. Look up the Ediacaran geological period. It was about 630 million years back. All we have are the fossils but it's pretty wild
If the existence of life prevents newly formed life from gaining a foothold, then abiogenesis could happen every 10 million years, but every time after the first time, it would get eaten immediately.
No, life could've started many times. For all we know, it keeps starting all the time, just never gets anywhere and disappears before we discover it. Also, life eradictes life and traces of life. On our planet, there's also geological "life" that complicates things.
"the universe is teeming with life" needs qualification I think, due to the mind-boggling scale of the universe. If the observable universe has 2 trillion galaxies, and each galaxy has one planet hosting life, then you could say there are 2 trillion inhabited planets. That sounds a lot, but because the universe is so huge, the chances of travelling between galaxies is about zero. So the universe could have a vast amount of life on a numeric basis, but the inhabitants of each inhabited planet will likely never encounter another inhabited planet, because the density of life is so very low. Of course, if life does start early and often, it begs the question : why have we not detected any other advanced civilizations?
The density could be MUCH higher, and we still couldn't detect them (currently, possibly ever) Make the following assumptions: We advance to the point that interplanetary voyages (and limited (or maybe even "moderate") resource use within our own solar system) is possible but hard/expensive/not economically worth doing on an extremely large scale (maybe mining asteroids etc, but not a fundamental change to the point where much of humanity lives off of earth in a dyson sphere) Voyages to other stars are "possible", but not really very viable other than for scientific curiosity (with fairly limited returns, incredibly long time periods (significantly sub-c)) And those voyages could be at most equivalent to the apollo program (a one off (or a few) overall insignificant "visits" to the nearest possible destinations) but anything beyond that is just too demanding with too few scientific returns for the effort expended. Barring fundamental changes to physics, this is what I would consider "likely" as the apex of what is possible. Say we don't wipe ourselves out, and exist at that technological level for even many millions of years. How far apart could two such civilizations detect each other. Only a few dozen light years, and then you run into the problem of radio (or any other) signals getting lost in the noise. There could be dozens, even hundreds of such civilizations in our own galaxy, and they could never detect each other. Space is just too vast, and even the nearest star systems are just too far away. We live on an island on a vast ocean. We can see some other islands in the far distance, and even take our best guesses about what exists on those islands ... but they are just too far away to reach on the treacherous seas. We hypothesize about the existence of other civilizations on those islands, but are far to far apart to see the smoke or light from their cooking fires, and we'll never know. That's my assumption about the Fermi paradox.
@@missyandmartinbakalorz1725 Interesting comment. I would expect that the density of simple life is much higher, and follows some sort of "long tail" distribution. So in our galaxy there might be a billion planets with single-celled life, a million with multi-celled life, and ~1000 with advanced life, like primates. Then advanced technological civs that can be persist for a significant time might be 1/1000 of those... A billion planets with life sounds a lot, but there may be 3 trillion planets in the galaxy.
Well we know lots of things but when you learn one thing there's more things to learn. That's more accurate if you know nothing there's nothing to learn. 😅
5:10 Abiogenesis has to be the most common occurence in the universe. My spouse is adamant it takes place even in completely closed off sterile systems the moment you take your eyes off of them. For example, if you forget to put away the milk cartons to the fridge the nanosecond you come home from the store, they are apparently immediately teeming with life and need to be thrown away.
That is not abiogenesis. Abiogenesis is life coming from inorganic molecules. If you had pure chemicals in a sterile container, life arising from that would be the first documented ocurrance. There are pre-existing microbes even in pasturized milk
She's not wrong, but that's because life is already present. If you mix vodka with a juice of some kind to an ABV of 9% and leave the container open, you'll get a nice vinegar just from bacteria in the air. Or if you leave the juice out on the balkony, you'll probably get a wine. Life is fascinating.
Suggesting there is no other life in the universe is like pulling a drop of water out of the ocean, not finding any life and then claiming there is no life in the ocean.
I am willing to believe that there exists life outside our planet, but your analogy is grossly incorrect for several reasons. The main reason is that in any drop of ocean water... you would actually always find life! Bacteria, phytoplankton, zooplankton, protozoa and algae, and even marine viruses (that one could dismiss as "not alive", although discovering a virus on Mars would probably be equated to discovering life...), you name it. Another reason is that we are in the exact opposite situation compared to your analogy: we have one example of a planet with life, and we want to extrapolate to the other planets/moons of our solar system, our galaxy, or other galaxies to infer if they may host life. Next time you find an ant in your bed, ask yourself if your bed is full of ants! 😁
Thanks to GroundNews for supporting this episode! Head to ground.news/CoolWorlds to save 40% on the Ground News unlimited access Vantage plan with my link. Let me know if you think Earth-like conditions are common or rare, how special do you think we are??
This video seems to go against your paper 'An objective Bayesian analysis of life's early start and our late arrival'. We are orbiting around a third generations star. There has been a ton of time and space for life to develop into civilizations if life is easy to form, yet we seem to be alone.
Ground News is a good sponsor. I like them. I use them. Good information -- good information _sourcing_ -- is essential for being a participant in democratic society.
@@TheVigilante2000no it uses the results of that paper! You highlight lack of intelligent civs, which is fair but a different process to abiogenesis (which this video concerns)
One factor to consider in these kinds of analyses if applied to all potential alien biospheres is that the CO2 and temperature constraints on photosynthesis and plant life on Earth need not be universal. Alien lifeforms could potentially evolve other forms of photosynthesis that have different limitations. There is also the possibility that an intelligent civilization could arise from a biosphere that never evolves oxygenic photosynthesis and instead ends up with some other process for primary biomass production.
Given perfect conditions the genesis of life may be easy, but I still think that the likelihood of perfect Earthlike conditions are prohibitively rare. SO much had to go perfectly for the Earth to be where it's at right now and to be so protected from constant asteroid bombardment, and to have a sun that wasn't too deadly for the ecosystem, as well as not too close to any stellar killers like supernovae or gamma ray bursts, and there had to be enough asteroid bombardment to deposit enough water onto the planet to support the development of life, and the planet had to be big enough to keep enough of an atmosphere but not too much, and the tilt had to be good enough to allow for a proper water cycle, and so on ad infinitum. Earth, is just super, incredibly, rare.
We have no idea if any of this is significant, required, or rare, or if we're just retroactively finding connections, as our pattern-seeking brains always clamor to do. As David says in this very video. We have to live on *a* planet that supports life, but that doesn't mean there's any special significance to how that planet is. It's like assuming only white people can win the lottery because the one lottery winner you've encountered is white. Well, they can only have one skin color. Doesn't mean there's any significance to what skin color that is. All Earth's configuration tells us is that this configuration does support life. It says nothing about whether this configuration is required, and definitely not whether it's rare.
I know that many would not want to talk about supernatural factors but has anyone also considered the fact that besides life on this planet, we have the perfect conditions for PERFECT total solar eclipses? I ask anyone to calculate the odds of that occurring anywhere else in the universe of 200 sextillion stars
@@Erikaaaaaaaaaaaaa You need to pay more attention to Organic Chemistry. The complexity needed for life requires Carbon Chemistry, and the environments where Carbon Chemistry can dominate are extremely limited. Liquid water, no ionizing radiation, stable temperature range, etc, etc. All of these variables must be maintained for Billions of years. It's just the science.
"Incredible rare", well, nobody knows how rare. But it's not unreasonable to suspect pretty rare and yes, maybe indeed incredible rare. What we dó have a reasonable estimation of is the amount of planets in the known universe. An INCREDIBLE amount. Soooo.....
@@ksh95 We have absolutely no idea that carbon chemistry is required for life. For example Gerald Feinberg and Robert Shapiro have shown how one could use a system of magnetized particles as an alternative to DNA. In other words, we don't even know for sure that *biology* is required. You are building your entire thesis on a series of unproven assumptions. You might be right, but just like OP there is no way to know whether you're retroactively finding patterns where there are none or whether you're actually onto something.
Simply put a sample of one data point is a data point. It is information. If we had a sample of zero, no inference would be possible. Nothing magic happens in going from 1 to 2 data points, but something does change from no info to some!
But... With one data point there's no way to tell anything about the actual population. Like, the one data point looks the same whether deviation is massive or minimal, and outliers look identical to data points that are representative. I'm not sure the magic is much greater from 0 to 1 than from 1 to 2. But I'm also an idiot with a Com degree so... I'm hoping some 3Blue1Brown crossover fans can come explain the math.
Ha! There you have a point. As long as we do not see (physically!) any other planet with a biosphere, we cannot set our own data point. All we have are planets (lots of them) from which we can tell „no life“. It is like guiding a caravan in the desert to the next oasis by just following the „No Water Here!“ signs. And basically that is the root problem of the Fermi paradox.
It's possible to do probability with a single data point (for example, estimating how many tanks the enemy has by retrieving a single serial number), it's just that you shouldn't expect much precission.
@@CoolWorldsLab Really? I thought that going from 1 data point to 2 data points is more significant. I am no expert, but my reasoning has been that if we have only one data point,the odds of life could be anywhere from 1/(10^1000), which is basically zero with the exception of our own planet, to 1, which means every planet has life. But if we add another data point, suddenly our chances skyrocket. Now I am reconsidering this.
“We will show them Our signs in the horizons and within themselves until it becomes clear to them that it is the truth. Is it not enough that your Lord is a witness over all things?” Quran 41:53
Honestly man, your knowledge, presentation, and most importantly, your narration skills, are otherwordly. The latter is what keeps me glued to the screen and never notice when minutes fly by. I'm infatuated.
👊
I, too, am infatuated.
*throws Dave his sexiest pair of undies*
He's the best scientist in YT right now.
Keep it up!
The only person i trust on YT. So glad I found this channel.
In terms of narration, apart from Brian Cox so far the only one who can convey the awe of science as succinctly. Really love the shit out of these videos!
Long form content that I watch multiple times to catch all the nuances. Man, don't ever change. You are one of the best things online, not to say on TH-cam. Thanks.
Long form content 😂😂😂 you just mean a video?
😂 so a full video and not a “short “ you actually make yourself look wholly cretinous whilst attempting to sound smart! 😅 🤦🏻♂️
Sooo not a short! Don’t be pompous 🙄
Your voice is perfect for this stuff, the cadence is unmatched and really emphasizes on peoples curiosity, and affects the ability of our attention spans to really get in and watch it all the way through. Thank you, keep up the great work.
Borderline ASMR
He talks incredibly fast without sounding fast and rather relaxed.
I prefer to read. Listening is ok for stories but with stuff I want to absorb reading is my go to medium.
i play this in the background while playing pc and mobile games at the same time
He by whom you are so hypnotised, *Knows* nothing, because he cannot, because he is a *believer* - he simply cannot help it, has no choice but to believe, because that is what religion(defined as any set of related*Unquestioned* beliefs assumptions presumptions[and occasionally norms] or simply any set of related preconceptions) does, It simply preconceptions does to men (human beings/dreaming machines) it preconditions them to accept without question or believe or predicates or conditions the reason. Believers simply*Cannot* know(directly immediately personally experience)
I wish more people were this happy and excited when they’ve been shown to be wrong about something. Respect.
You could worry about yourself, not other people's perceived faults.
@@richardmlouis Why are you like that? Maybe the little guy is happy because there are other people that are more aligned with his own thoughts and philosophies. We are humans and social animals. It's always nice to see like minded spirits.
@richardmlouis feeling attacked old boy? Suffering from entrenched opinions that refuse to accept reality? Or are you just a drag? Do tell...
@hvbris1 absolutely mate, that's a scientist right there...
You are the best science channel on TH-cam
Seriously TH-cam.. stop putting ads in mid-sentence. When it comes to science and lectures this is ridiculous it takes away from the content. Thank you Dr for another excellent experience.
Premium is a game changer, it pays off given how much time I spend on TH-cam
TH-cam premium is actually worth it. Content is so much more enjoyable without ads and your video views support the content creator just as much as if you had sat through the ads.
@@viacheslavkiselev3125and honestly, it's not that expensive
Since TH-cam started making the advertisements more and more punitive, I consider it a moral imperative not to reward that with payments. Customers... Demand better.
Ads are actually placed by the content creator. They clearly just hit the 'distribute randomly' button.
Prof Kipping, I hope I can get to the point to be able to financially support the work you do, as the sheer amount of enrichment and education I’ve gotten out of your channel is immeasurable.
Till then, thanks to everyone who can and does support, and thank you doctor kipping for continuing to bring us these amazing videos
Don't be silly, he makes 50x your income, save your pennies
@@justadildeau Haha. 50x might be an exaggeration. But yeah, David is fine. It is okay to donate though. Why not? David is a planet 'hunter' and trying to understand our surrounding. It is what I call consciousness. I need to be conscious. It gives my life meaning. If David can contribute to that consciousness, he's more than welcome. I think it is perfectly reasonable to support a guy like David that has more resources of achieving that goal.
@@Nobody-df4is sure, waste your money, it's yours to waste
@@justadildeau It is not a waste if you can afford it. And again, I agree, David doesn't really need it. He's fine. Stay safe bro and spend it wisely. Cheers!
@Nobody-df4is suit yourself🤷🏼♂️
Man I consider myself lucky to get to hear you talk. Thank you for the way you approach topics and your honesty while presenting facts. You are one of the best modern educators out there.
Simple life is easy, complex life and advanced civilization , very very rare.
Your channel should be a mandatory viewing in all schools. There is a sense of awe in every single frame amd i love it. 😊
Imagine if you made learning about the silurian hypothesis mandatory.
Love your content professor ! Your recent appearances on podcasts were a gem to watch as well
I'm glad you finally raised those caveats at the end: just how "earth-like" (this is likely a multi-dimensional "parameter") must a planet be for statistics like these to be calculable? Moreover, we can't exclude the possibility that some verrry different variety of life may arise & evolve in a similarly different environment. We can't begin to address these questions until we've surveyed a multitude of exoplanets in great detail. Or at least until we find microbes on Europa or Enceladus.
At the other end of this, I agree with Steven Hawking that encountering an exo-civilization is dangerously inadvisable, as the likely disparity in level of development may mean that one will overwhelm (e.g., destroy) the other, or that the greater will regard the lesser much as we currently view colonial insects, or corals.
🦖? 🐒? 🦜? 🐠? 🐝? 🦂? 🦠? (?!)??
To me, the terrifying solution to the Fermi paradox is that life is common but so short that the chance of two civilizations noticing each other are infinitely small. We pop into existence that would be noticeable and disappear so quickly that anyone watching our solar system blinks and misses us.
Or... The rare earth hypothesis is true... And complex/intelligent life is extremely, extremely rare in the universe, because you need goldilocks conditions fore life to evolve to that point. Maybe Earth conditions are so extremely rare, that we are alone in our corner of universe. Despite life being so easy to thrive.
Radiowaves would remain and travel for ever across the galaxy. So, briefness of civilizations is not the answer.
@@ianthor22 I’m afraid that solves nothing. If a civilization was broadcasting for 300 years, you still have 300 years to detect it when the waves pass by you. The fact that they travel forever does not help at all.
There are thousands of possible solutions. Coming up with solutions isn't the issue. The issue is proving them. This, just like every other possible solution, is totally inconsequential.
@@ianthor22 Our radio communications are only detectable at 1 ou 2 light-years away from Earth. If we were trying to actually send a signal to outer-space, that could change the numbers significantly. But at best we would be able to deliberatly send a detectable signal to a hundred light-years planet.
By the way, our galaxy has a radius of 52 850 light years.
Complex life has had multiple hard resets through extinction events just in the past 600 million years. It's just not something that can ever be calculated or predicted in a sample size of one.
I tend to agree, but I am too lazy to definitively critique bayesian based statistical analysis; especially when applied to data points representing one instance.
Soft resets. Multicellular life never had to evolve again from scratch. Once multicellular organisms arrived, they stuck around. At least until today.
True.
However, it's easy to simulate larger sample sizes.
If anything the fact that thea sample size is one tells you that life appearence from scratch it´s a rare event, because it never happened again (any new life appearence would have a different genetic code becasue there is no causal link between the codon and anticodon in the tRNA). We just don´t know how rare. I´m rusty on Poisson distribution but a once in 4,4 billon years should give a better estimate that guessing that life appears 200-700 millon years after it becomes possible
The dinosaurs were wiped out which created space for mammals to evolve. If they hadnt been wiped out would we be here now?
I enjoy the type of videos you make but what makes me come back everytime is how your passion can be felt through the screen and you always make complicated subjects so much easier to comprehend for an average joe like me. Keep it up!
This is the kind of content that got me hooked into studying Geosciences and also into Astrobiology. I cannot get enough of talking, thinking and in this case, listening to the passage of time that is just beyond human imagination. I find it incredibly tempting to think of former advanced civilizations that inhabited the Earth; its thrilling to think of their come back or maybe secrets they have deployed for future civilizations like us. Quite frankly, despite all the craze in the world right now, its mind-boggling, what humans are mentally capable of.
Professor Kipping, in the past especially your public lecture on the Cool Worlds Classroom Channel did a superb job in convincing me, it is likely we might be alone in the galaxy and even the universe. Like you said yourself: As the arguments in this video are only valid for an exact copy of Earth, this new discoveries about LUCA are interesting, but don't change much as we have still now idea how common "Earths" are.
Thanks anyway for the entertaining and informative video!
Another thing. COMPLEX multicellular life only has about a 700 million year history. So much had to evolve, AND atmospheric O2 had to sufficiently increase to cause more bioenergetic pathways to evolve. In addition, what if a large meteor had NOT impacted Earth 66MYA? Would we be here now??
Need to be looking more into Earth's evolution, it's like looking for a needle in a haystack with no haystack until they know more about how life emerged here let alone anywhere else.
Non-avian dinosaurs would still be around if that large meteor didn’t hit Earth 66 million years ago
@@yancgc5098possibly they might be quite smart by now also?
@@simoncove1 Possibly, though primate brains are legit just built different so probably not. Though we would certainly see non-avian dinos adapt to the glacial conditions of today’s Greenland and Antarctica, so that’d be cool to see
@@yancgc5098 small mammals did exist tho even back then so maybe anyway…. Might be inevitable give a planet like earth and long enough. Also yeah the continents allow ecological niches but yes let’s face it…. Who knows?!
LUCA is usually "last universal common ancestor". Lowest doesn't really make sense because lowest suggests the earliest, presumably somewhere back in the fuzzy weirdness of abiogenesis
I don't even see how "lowest" would suggest the earliest. It just doesn't make any sense. Maybe lowest on an upside down tree of evolution?
And FUCA is the first universal common ancestor, yes I knew lowest sounded wrong.
LUCA means all life descend from this ancestor, it doesn't mean it's the first, just that this ancestor is the ancestor all modern life descend from. LUCA is not the first self-replicating molecule.
yeah why did he say lowest
@@al-Assas Exactly, Lowest Common Ancestor (LCA) is a common term when discussing trees in computer science so given prof. Kipping likely had some exposure to cs/programming, it makes sense that he misspoke here. LCA is the last shared ancestor between two nodes in a tree. In this context, "last universal common ancestor" would therefore mean the same thing as "lowest common ancestor (on the tree of evolution)".
This is hands down, one of the best YT-channels ever made. This channel is so well needed in this ocean of drama, depressing news and jump cut attention span destroying content. :P
Thanks for dropping this video especially as we all know your extremely busy atm it's most appreciated. ❤
Saving this for bed. Thanks in advance for another thought-provoking video. Just finished watching this. I firmly believe that life started quickly but developed slowly. Things like the boring billion were necessary for the development of more complex life. A great channel for the evolution of life is The History Of Earth.
You won't be able to sleep because it will have you thinking lol.
@@JedEckert Just have to put it on repeat 😊😀🤔
...not exactly a bed-time video for me. I had to rewatch it at least twice to grasp (and criticize or support) his arguments.
@@JedEckert lol, that was my comment as well ; before I read yours!
I will also point out that boring billion was also a break-point for life on earth. That is, it was either the stepping stone for more complex life or.. if plate tectonics had not started up again, it would have been the end of the habitable earth.
I will watch every video this Professor makes. His voice is like butter melting on a stack of pancakes.
Yeah, that's my standard for the legitimacy of science information. When it's delivered in a voice like butter melting on a stack of pancakes.
@@DMichaelAtLarge Legitimacy is peer reviewed publications. If you have objection then disprove his paper by writing your own xd
@hungrypanda4506 you missed his point. Cute try tho
Yeah@@hungrypanda4506, you missed my point, apparently because you have no sense for satire.
I find it weird that an event that has not happened yet (extinction of life on Earth) somehow changes the probability that the start of life was easy.
He is unknowingly using causal fallacy.
yeah like humans aren't going to be able to increase the amount of c02 in the air in 1 billion years?
@@ticketforlife2103I totally agree, although your fingers have played a trick on you, as casual is rather opposed to causal... ;-)
Im gay ;-)
This is why it's usually best to resort to Bayesian inference to decide statistical probabilities. The human mind is not good at interpreting statistics and can easily fool itself. Then we have various cognitive biases to deal with.
Great example of appearing to be rational. It's not about time, it's about the conditions favoring certain breakthroughs, factors that do not fit a regular temporal lattice.
Thanks Dr. Kipping! Always love your videos. You help keep me thoughtful and curious. ❤️
Gonna withhold any kind of anticipation of intelligent alien life until n>1
And even the intelligence of our n>1 is not quite sure...
I will agree, when we stop destroing our habitat and learn to think and plan on longer timescales.
@@AndreasSmolka I just think it's a major reach to assume that 1. Life emerges from random stuff, since nobody's replicated this in a lab yet, so still n=1 there, and 2. Nobody knows how to define "intelligence" yet; it's all over the board. As soon as one person says it's cognition, language, civilization, etc., another says "yeah but chimps do all that." I don't think most scientists even take human intelligence very seriously. They were convinced by Carl Sagan and Frank Drake we needed aliens to help us get out of the Cold War; they were wrong, and they're still wrong
@@AndreasSmolkawere gonna need to stop aging for that.
That’s a beautiful comment. I’m quite surprised that Prof. Kipping didn’t place more emphasis on this. Usually he comes across as the dilligent conservative scientist to me, and although he doesn’t actually say anything specific he changed his mind about here, and is very up front about all the "this COULD mean", "that MAY be", "what if" and so on, I find it to be quite out of character for him. In a disturbingly TH-camr-science’ish-clickbaity kind of way. Then again, that may just be how you have to play to promote actual science on social media.
@@AndreasSmolka there's no question that we're intelligent; the issue is whether we're self-destructive. I don't see the two as mutually exclusive.
Who is watching in 2084 🎉
Who won the 2024 election?
I'm dead.
Trump.
I'm 86yr can't believe 🤲🏻🤲🏻😭🐔🫣🐢
Quomodo, nunc id quod duobus bis annis factum est, imperium Romanum adhuc totius mundi princeps est
This stuff gives me such an existential crisis knowing that I’m dying like 50 years from now
@@Anthony-ru7sk I’m 50 and know when my time comes
Amazing discovery that you know when you'll depart this realm. I'll assume you intend to deliberately pull the plug in 50 years😂
@@justadildeau What? you did´t get you death day with your life´s instructions manual?
50! You're lucky! Wish I could rely on even the next 10.
Just think yourself lucky that you existed at all. Who's to say the people in a 1000 years time will be any happier than us. One presumes they'll have tech and knowledge far beyond what we can conceive but the human condition will remain the same.
There are numerous variables that could easily sway the conditions. From meteoric bombardment, to plate tectonics, star stability, solar flares, radiation, specific chemical ratio... And so forth. Then you have to have the right time frame as well. When taken all of those things into consideration, the number you get is miniscule.
a lot of emphasis - so much so that I did not understand a word - well, I understood what You said, but my brain did not process it due to the "backgrund noise" / the emotional charge - I was disrupted
I think the problem with the Fermi paradox is that interstellar travel is too big a barrier.
We hear that events on Earth going back billions of years were such that life was nearly wiped out several times for various reasons.
It is hard for me to see how one can use the time scale for how life evolved on Earth and apply it to other worlds with any expectation of being similar for another planet.
You wouldn't use that time scale though, you would go to the closet star which would take ~130-350 years will current tech (Orion Drive), then you would mine all the asteroids and debris around that star and use it to make a Dyson Swarm, maybe also mining the smaller moons and planets, then you launch ships to the closest nearby stars again, it would take a blink of an eye on geologic timescales to colonize the entire galaxy, doing so is theoretically possible with our current tech.
@@cy728 we can’t even colonize the moon after half a century after first landing on it. We can barely maintain a low earth orbit ISS and it costs an eye and a leg. Imo these speculations often ignore that what is theoretically possible is very different from what is economically and practically possible irl.
@@pansepot1490 u are correct for economic concerns can and has prevented advancement for decades now. Why switch to renewable resources when that ruins big fossil fuels profits? Why explore space when profits might not even be guaranteed in this life time?
The reason it’s so easy to ignore economic concerns is cause unlike gravity or the vacuum of space, it isn’t a real problem to overcome, just one we’ve created for ourselves.
@@sleepninja2350 The implication here that renewables are "more advanced" is weird, because usually the person that favours renewables doesn't even make that case; they make the case that they're less polluting or something (and that's their entire case).
@@pansepot1490 The economics of space colonization change once you have a sufficient industrial base actually in space. We currently don't have a significant production capacity outside of our planet, so we have to haul all of our equipment quite expensively out of that pesky gravity well.
Another explanation for the early onset of life is panspermia. A smaller planet like Mars would presumably cool down and become habitable quicker.Even interstellar panspermia can not be completely ruled out yet. That could make single celled life reasonably common in the galaxy but still possibly extremely rare in other galaxies.
I'm betting on interstellar panspermia... bacteria ejected into the early universe from an older one. I am not convinced the age of our universe supports the challenge of evolving life in our simplest form unless it really is just anthropic principle explaining everything.
Ye great point, I was tempted to talk about that here but didn’t want the video to explode in length, I’ll definitely talk about this in a future vid 👍
"The universe must be teeming with simple life."
What I've heard: there's an endless amount of microscopic pathogens.
Not necessarily. Bacteria cause infections, but have you ever heard of an archaean-caused disease? Archaea are extremely common yet the only health conditions associated with them tend to be imbalances in the already extant microbiome. Granted, archaea are more closely related to eukaryotes (and multicellular life) so maybe alien microbes would be pathogenic, but considering alien microbes would have nothing to do with our own biological processes then it would probably only be sheer coincidence if they're harmful.
Pathogens jumping hosts happens but between mammals. Anything more different just isn’t compatible.
If the world doesn’t have multicellular life they aren’t adapted.
@@yannicmodritscher4646
True only for viruses. A bacterial form of life could adapt to more or less any environment with a supply of nutrients - e. g our bodies. It would then very likely produce chemicals toxic to us.
@@yannicmodritscher4646There are these recently unearthed mimiviruses that have allegedly caused upper respiratory infections, but they don't seem to be infectious.
A pathogen requires a larger, more complex host to infect - so there couldn't be a world inhabited only by pathogens. There may be lots of worlds, however, where life never gets beyond the level of the single cell.
I know it sounds bad becuz it’s sounds like I only watch to hear what I want, but it’s nice to hear you more positive on the likelihood of life. That is because I respect your intellect so much
I love how excited you are about all of this, it's contagious.
Great video. If intelligent life is practically an inevitable outcome of life, and life comes easy, there is still the question "Where is everyone?".
needle in a mega haystack , i feel we don't quite have the tech too search for life
Short answer: very, very far away. I find it stunning that few people tend to grasp the implication that the vastness of space brings. Even if one assumes there are a million civilizations roughly equivalent to ours (at our stage of development) spread throughout the universe, the distances involved makes contact highly improbable, if not completely impossible at any stage.
@@siubhan2047 some communicative discord could be possible , we can't for see tomorrows tech , same goes for traversing the galaxy , physics is ongoing we nowhere near answering or discovering everything
First episode of the Twilight Zone!
Homer Simpson waving back at ya from a planet 100 million light years away.....
The art of talking a long time about what we do not know.
I have to confess that I'm not sure I accept that life occurring very early necessarily implies that it's likely to occur. Certainly if there were many planets like ours, and life always tended to occur early, that would be compelling. But with exactly one data point, it seems like "maybe it just happened to occur early here - regardless of the odds of life occurring". Am I missing something?
Right I give this argument fairly explicitly at the end
@@CoolWorldsLab boy, do I feel like a numpty! I thought I watched and listened carefully. :(
OK - I went back and reviewed it. I feel at least a little less silly now. I think we're talking about different things. You're describing the rare Earth hypothesis - which is certainly a valid consideration. Not only may it be important to have a planet extremely similar to our own, but perhaps it also has to go through some of the same changes as Earth.
What I'm asking is a different question. Perhaps abiogenesis would be a very common thing under perfectly ideal conditions. But perhaps not. It could be an astonishingly improbable event even under the best circumstances. I think the notion that it occurred early on Earth is used to "prove" that it's a very likely event under the right conditions. But I'm not sure we can make that leap based on a single case. Perhaps it's an incredibly unlikely event that simply happened to occur quite early. If I'm right, we would only be able to know this if we saw how quickly it occurred on many ideal planets.
@@Rick_Cavallaro The thing is, because we have only one sample (earth) its logically more probable that we are the norm as opposed to the exception. Therefore we can extrapolate based off that as this video does, but if we are the exception (as your suggesting) then the math changes.
@@user-ga5fne3h I'm not suggesting that we're the exception, I'm only asking whether a single data point can tell us anything at all about the probability that abiogenesis is a likely event under the best of circumstances. I admit that the fact it seems to have occurred almost as early as possible in the one case we're aware of would make us inclined to believe it's a highly likely event, but I don't know if the math bears that out.
>> because we have only one sample (earth) its logically more probable that we are the norm as opposed to the exception.
I also don't see how that follows with only one data point.
Hey Cool Worlds changing his mind? This is why I remained subscribed to you. I disagree with your conjecture on certain topics, but I respect you as an academic and I am absolutely happy to hear someone as highly educated as you changing your stance on the odds of life.
I really love your channel. You’re clearly very intelligent and educated. Yet you still have an open mind for the potential future of science and its discoveries.
I’ve met many highly educated and intelligent people who are completely unwilling to bend any beliefs on science or otherwise.
You are an inspiration. Keep doing the fantastic work you do.
I truly think we will be kicking ourselves in 100 years, that the signs of life were everywhere...
I would take the opposite bet, in 100 years we will have not detected signs of life elsewhere. I wish I were around to see the result!
@@bobcousins4810 Then I hope my assumption is correct, my friend 😁
I’ll take the in between. We won’t see them in 100 years, but not cause they’re not there but because they’re so advanced they can keep earth in essentially a nature reserve forbidden from the public.
I don't think it's likely that we will ever receive a signal from aliens because im assuming they would only send signals to stars where they can observe planets using the transit method and the chances that they are at the precise angle to even make that possible seems very unlikely also since they could be so far away i don't think they could predict where our star will be in the future for them to even aim the signal at due to random variables
Life: Yes .... Intelligent life: How would one jumped up species of modified chimp define 'intelligent'?
I am not of a sciency background but love astronomy and astrobiology and sciency things..I really found myself not understanding the technicalities of the video (frustratlng) but watched and tried to grasp as much as possible..thats the sign of a good teacher, to inspire..this is indeed exciting stuff!
It helps to check out the cool worlds videos. The ones from 5 years back are great and help to give a better context to his current videos. This video especially depends on watching all of his videos addressing the Fermi Paradox and the duration of life on our planet. Most of them require very little math beyond simple logical analysis and graphing comprehension.
14:20 - Aquatic plants regularly work with single digit ppm CO2 dissolved in the water without any access to the air.
This was one of your more optimistic videos, (with obvious caveats), love your robust analysis.
Please, continue thru Cool Worlds to make lots and lots of podcasts! Kindly allow me to echo the immediately foregoing comment, "Honestly man, your knowledge, presentation, and most importantly, your narration skills, are otherworldly. The later is what keeps me gluded to the screen and never notice when minutes fly by. I'm infatuated."
If life gets going relatively easy, an inevitability of some kind of assembly/ information theory, then why is all life descended from LUCA?
And why can we not find any life precursors anywhere on earth?
If life were easy, shouldn’t there be signs/ evidence of new life attempting to create itself all the time that we can detect?
Well, it's not as easy as that. Life could have started easily in the conditions on the young Earth, but conditions have changed, and life might arise with more difficulty now. Second problem would be that new life appearing would be an easy prey for established life forms like predators. In many online build-and-wage-war games, time-in is a good predictor for your success. The same will generally hold for life. It's like a pyramid game really.
@@florisv559 new life wouldn't necessarily be nutritious? e.g. left handed sugars
@@TicTac2 You forget that many animals eat plastic, mistaking it for food. And left-handed sugars can be eaten by certain pathogenic bacteria.
Take it easy. Remember that only a vanishingly small number of organisms that ever existed, "live on" in the form of fossils, and we will find only a few of them, because many are buried deep inside the rocks or they have been destroyed by metamorphosis or erosion.
Many attempts to start life could have failed very quickly, either by being eaten or by being at the wrong place at the wrong time. But once it is there to stay, it will have to compete with the already existing life.
And for all we know, some life forms that now exist, with different DNA encoding, might well be the result of a separate origin, if the RNA DNA path is inevitable on the road to life.
There's a big big big difference between a civilization and "life". The odds of life and the odds of a civilization should never come close to being mixed in any way shape or form. It'd be like mixing the odds of ever having a date in your life VS the odds of sleeping with super models your whole life, becoming a rock star, and super rich. The Huge part is going from mere single celled organisms to multicellular organisms and making that leap. And life existing on this planet will last longer than 900 million years (assuming no planetary collision or change of orbit toward the sun). Life at the bottom of the ocean is one example of this, and I never heard of people believing No Life would. That's why it's a problem equating life with advanced beings that's on a totally totally different plane.
Very underrated comment.
Too often I see astrophysicists talking as if civilisation is _on average_ a necessary consequence of life on a planet, and drawing statistical conclusions from this assumption.
If we look at palaeoanthropology, we see that even intelligence (Homo sapiens and our close cousins) is not guaranteed to develop civilisation (agriculture, cities, metalworking), let alone a technological one like ours. The time from the emergence of our species in West Africa to the Neolithic Revolution is 95% of our evolutionary history, and we could've gone completely extinct several times during that interval. Which intelligent species would have taken up the mantle of civilisation? And when?
Add to that the fact that space travel is probably unfeasible (unless we're missing something big in our physical laws, all we can do is send out probes that will _maybe_ reach their destination in a few millennia and _maybe_ report back to a civilisation as far removed from us as we are from the ancient Egyptians... Why should we do such a thing?) and we can see that Fermi's question isn't at all difficult to answer.
My biggest issue is your time frame. It's all based on OUR solar system. There are trillions of solar systems over billions of years. There are untold numbers of solar systems that have been around for 10 billion years. 700 million years (based on one case study) doesn't seem that long. Great episode.
Ohh that's a great angle. Makes sense. The variety of conditions is immense. As soon as that big new ESA telescope start running and gathers the exo planets data we can start adjusting these theoretical boundaries
Well, if you would have watched any of his previous vids. That was EXACTLY his argument. I tend to disagree, because it's fact. We exist and therefor it is evidence. Sure it is one example, only but it is all we got. So, I'm going to draw conclusions from that one example.
As human, I get humbled in front of the universe and it's grandness. As a vlogger, I get humbled in front of Cool Worlds and it's majestic content. Thank you David.
Once again loving both your intellectual honesty as well as the way you narrate your videos!
IMO: any reference to Earth is (largely) irrelevant. All that really matters is if there are other planets with the key features needed for life to start in the first place. We simply can't answer the likelihood of such via reference to Earth.
Why not?
@@mryellow6918 because we dont know what is required for life to appear if we only have one sample?
13:30 surely in 900 million years from now we would just convert whatever was needed into CO2 and pump it into the atmosphere to maintain what ever biosphere is left at that point in time, therefore, extending the habitable period?
That's exactly what I thought 💭
OR we could start now by driving SUV’s?
We should start leaving now. And it wouldn’t hurt to move our orbits. A half million years might make the difference.
Or just move the Earth out a bit. Move a big asteroid to fly by the Earth at regular intervals and drag the Earth out. I'm sure we'll be able to that in a 1000 years, much less 1 million.
@@AlexRussell-kd9pd
10 m per year, over billion years, 10,000,000 km, sufficient to cool the planet. Wouldn't try such an orbital movement in 1000 years, too much risk of earth quakes.
Three thoughts:
1) Evolution rate is quite variable. The coelacanth, sharks, and alligators are all examples of life that have changed very little of hundreds of millions of year. Human could considered the fastest evolution rate since we have clearly definited intelligence yet have not beeen around very long (relatively speaking). The real trick of there being other intelligent, and even space faring, races is what factors sped human evolution and what would the maximum for those factors be? Even on a planet with a shorter life span or less ideal conditions an intelligent race could evolve if the evolution factors were strong enough for force it without reaching extinction levels of stress.
2) Planetary life span is only being calculated based in non-interferrence. If a species becomes intelligent enough and aware of issue affecting the planatary life span, they could take actions to reverse or slow down the dying process, gving them time to evolve and advance more.
3) Even if life on the surface of a planet becomes overly stressful, it could move underground and still develop to become intellgent and spacefaring. Basically, life finds a way.
I know that i might sound like a jerk, but your arguments would be more compelling and logically rigorous (against critics and trolls) if the phrasing of your essay was proofread and corrected. For me, proofreading also helps to identify arguments or statements that are heavily based on my emotional state or personal bias. I am trying to be a friend with the previous statement. Addressing your statement: You make three compelling arguments that seem to make the case that the life-span of our planet is very different than the one Professor Kipping has stated. Your first statement may be correct; however the difference in time for rapid evolution versus the typical duration is small in comparison to the eons that measure the duration of our planet. But, data and scientific analysis could easily prove me wrong. I agree with the second and third points. On the second point, it seems obvious that if we can easily imagine ways to: move our planet; 'terraform' other planets and even adapt our species and intelligent machines to thrive in hostile conditions then the life-span of our planet and star will be extended. Our effective life span would then be indefinite. The survival of humans and our descendant species or machine intelligences would then only depend on the total amount of usable energy and materials available in our Solar System or nearby star systems. On the third point: microcellular life on our own planet has penetrated miles into the crust of the Earth according to scientific reports. Even after our entire planet was covered with miles of ice from pole to pole for thousands of years life re-emerged. This happened at least twice according to geologists. Multicellular life emerged and continued to evolve into the diverse forms of life today. We might be lucky among the few planets with emergent life or typically resilient survivors as you imply in your essay.
You have an excellent point. If you look at all the life forms you realize intelligence at our level is very rare AND not necessarily a good survival trait since saber tooth tigers can easily gobble us up.
Another point is if intelligence evolved in sea life, like the octopus. No fire, no quite a lot.
I think you have a mistaken idea that evolution has the goal of higher intelligence. Natural selection is about reproduction. Therefore, an evolution rate would quantity a species ability to adapt. Humans are actually quite slow, especially compared microbes. It takes over a decade for us to be able to reproduce and we don't have a lot of offspring compared to other species. That's a major reason why infectious diseases are so hard to fight. Microbes can adapt in days. Humans are far far slower.
@@marveloussoftware4914 Except that intelligence allowed us to out avoid them, out smart them, and finally out live them. Sure one on one they have the better chance of winning, but smarts ultimately won.
@@someguy999 No natural selection is about survival of the fittest. And fittest is a variable concept since it all about surviving the natural evvironment that you happen to be in. And the natural environment changes based on a number of factors like seasons, location, and natural hazzards. Being inteligent help to give one the greatest chance of surviving by being able to make tools to enable survival without necessairly evolving claws, hooves, altered eyesight, and such which would take very long time to develop. Intelligence is the ultimate Swiss Army Knife as long as it's properly applied. It's true in some cases it's has its limits based on the available resources, but generally it's the best survival tool, along with knowledge which is something most animals don't really possess. Having a mind that can learn, hold knowledge, and pass it on to the next generation ultimaltely leads to intelligence and higher survival rate.
Ah, the joy of learning something new that changes your outlook on something!
I grew up with learning about 3 states of matter and three allotropes of carbon and sunlight was required for life to exist - and am utterly delighted that we know better than that, now. Likewise, it's wonderful to hear that recent studies and discoveries indicate a higher likelihood of life starting easily than we previously thought.
I don't understand why most people are so dubious that life is common when we literally live in a big pit of life that randomly cropped up. It's all around you and in literally every place we look, in poisonous vents, in volcanoes etc. The occam's razor on this topic quite obviously slices on the "life is common" side.
Because people want to feel important. Life being elsewhere challenges their ego and their desire.
@ Yeah lately I've been realizing that everything really is that stupid. Everyone. Every person ive met. All of it is based on this weird idea that humans are special. Depressing shit.
It’s also unlikely that the first time single cell life got started in Earth, that it survived. Life would have started multiple times before something took hold.
Then multicellular organisms, did the first one of those survive or did it die? Again, probably the first one died before it could successfully evolve and take over.
The universe is very inhospitable for life. Infinitely vast, yet so lonely. A tiny change in the sun and it's game over here.
It blew my mind when I found out that our sun is unreasonably calm, unlike most other stars. We really are in the goldilocks zone!
@@ksh95If you knew almost nothing of the universe this assumption should be pretty logical to make. It shouldn't have blown out minds when learning it is a fact
@@ksh95 That was a study regarding Brown Dwarves but there are caveats to that
Well, its the ONLY place that is hospitable... soo
This is what changed Carl Sagan's mind, too many coincidences
As a biochemist with an interest in the origins of life I do not particularly care if life elsewhere achieved a 'technological civilization' state, but rather on the origin of what we call life, and in understanding what life is. I would issue a challenge that we can ask biologists and biochemists and most will not be able to produce a description of what life is that is truly universal, and not just relevant to terrestrial life. If the microfossil record is correct, i.e. it really represents structures that were 'alive' 3.7 billion years ago I would completely agree that life is not fussy. How long evolution takes, and the paths that it ends up in are irrelevant. It is only important for us humans from an antropocentric perspective, where we want some life, somewhere in the universe, to converge on a technological civilization, but as a biochemist that criterium is really not relevant.
Having said that, I think that as life's complexity increases also its frequency decreases. As a system that is in a continuous state of non-equilibrium thermodynamically, it will also require conditions that must be stable over an extended period. The higher the complexity the narrower the range of fluctuation of environmental parameters that are compatible with that complex life. Sure evolution will enable change, but evolution also working on a species and not individual level, it will also require long periods of time of stability.
That's a great point. If we consider our own impact on our environment right now, our chances of lasting 900 million more years at this rate are slimmer than the Planck length on a vegan diet. I take it you're familiar with Jeremy England's 2014 paper on the emergence of life as a highly efficient distributor of heat? I quite like that hypothesis.
It's not merely because we're chauvinistic about technological civilization that we look for it amongst the stars. It's more the fact that we ourselves ARE a technological civilization. If we hear nothing, if technological civilization is fleeting enough that it is undetectable on cosmic scales, what does that say about our future?
@@Stadsjaap - I strongly doubt any one complex life could reasonably be said to last 900 million years as numerous extinction events seem to prove but there always seems to be another to take up the batton
@@sja45uk I completely agree. The extinction events in Earth's past completely remodeled the biosphere as a consequence. In the absence of those, Earth's life makeup would be very different. As to life's origin, and life in general, biochemically I see it as a series of events (chemical reactions or physical changes) that as a result of a continuous energy flux tend to optimize the thermodynamic exchanges with the surrounding environment. Jeremy England is one of the latest in a line of physicochemical scientists who have been looking at this problem as such (Ilia Prygogine being one who in the 50s and 60s) started looking at dissipative structures and non-equilibrium thermodynamics). That is how I see life, from a biochemical perspective). Yes, there is much we do not know, but I think some of the researchers are on the right path. But it is something that we will never know for sure, how it originated on Earth. The best we can hope is understanding its principles and perhaps reproduce it (microscopic) in controlled conditions.
Do you have a working or provisional definition of complexity? It's often mentioned but rarely defined. Genome size doesn't work, as I doubt that anyone would consider an onion to be more complex than humans. The number of proteins doesn't work ("simple" worms like C. Elegans have similar numbers of proteins as us). Maybe the number of organs or tissues could work, but I haven't given it much thought...
you are a world class master at communicating this information to people like me who arent particularly educated in science.
17:30 That will be the _Silurian_ hypothesis then.
I don't know what the _Sirrillian_ hypothesis is but it sounds vaguely like a Tolkien novel.
😆
In Asimov's foundation the unsettled worlds of the galaxy all had a biosphere consisting basically of moss and a few other plants/ insects
You could have done the math for lower mass G type stars. Theyre similar enough to our sun, but can last upt o 30% longer giving intelligent life more time to evolve.
But would they be as quiescent as the Sun? I've heard that the Sun is unusually quiescent for a G-type star.
@@TheDotBot Yes, the sun is unusually, extremely quiet. How much this actually matters is uncertain, I think it is important. Everything about our solar system that is unusual should be considered important until proven otherwise.
Personally, I think this is because the sun's mass is perfectly balanced between the CNO and proton-proton chain methods of fusion, and this acts to stabilize it. (Lighter stars only do proton-proton and heavier ones do mostly CNO, but the sun does both). But I'm not an astrophysicist, so I could easily be wrong.
@@fluffysheap Interesting, as I understand it, the sun's quiescence compared to other G-stars is (largely) due to its slow spin at the equator and low magnetic field strengths, and that CNO cycles being a threshold thing would affect the sun's overall output stability but not surface activity, which is tens to hundreds of thousands of years away from the fusion reaction in the core.
Same disclaimer, I'm not an astrophysicist, so anything I say could be stuff I've picked up and completely misunderstood, or it could be obsolete knowledge or whatever, and I'd be more than happy to be corrected.
Hypothetically if the Europa clipper or another project discovers independent simple life but we don't have an estimate for when that life started, how would that impact the model?
They will going to make a new copium stuff because they still want earth/our solar system be special, but the thing is, more likely life/intelligent life is everywhere, like in Three body problem
This model is just for earth-equivalent systems so it wouldn't impact but it means the universe is surely teaming with at least simple life. Honestly the problem I have with extrapolating this model out to the whole galaxy is we still have yet to even find an earth like exoplanet.
@@ToxickysBruh not a single physicist I personally know wants earth to be "special". They salivate at the prospect of finding alien life
5:00 2 Things: 1) We aren't looking for intelligent life, just life. So a planet could be anywhere in the 3.7 bya-to-today time span and we could find life (based on prior assumptions). 2) Our evolution was catastrophically altered by the asteroid that killed the dinos. Thats a pretty low odds event that severly slowed us down.
One problem with this is that we really lack a genuinely operational definition of what life is. For instance, viruses are studied by biologists, and seen to be specifically linked to life as we vaguely understand it. As concerns CO2, there are several discussions that indicate that primary production - conversion of water and CO2 into carbohydrates - essentially stops between 200 ppm and 150 ppm. In addition, empirical data also shows that prmiary production is already limited to some degree by _low_ levels of CO2. This is shown by the positive response of desert margins to increased CO2 since around 1950.
Star Trek Voyager did a story like what those two Scientists suggest about Life emerging before we knew it ! It is a Interesting Premise.
“Distant Origin”. Yup it was interesting. Flawed but a very different story to the usual stuff.
Dr.Who beat Voyager to that one by some decades .... Google 'silurian hypothesis'
4:48 The weak anthropic principle wouldn't state that the existence of simple forms of life or intelligent life found here on earth proves that the process is easy. It simply states that the existence of life here proves that it is unremarkable. The WAP is a perspective about the existence of life's remarkability. It is an antithesis to creationism, or the strong anthropic principle, the WAP stating that SAP's analysis is based on a selection bias, i.e. where else would there be intelligent life to reflect on the remarkability of its existence than the place where it happened. Anyway, to my original point, the WAP would state that even if earth is the only planet in the universe with life on it, that is still proof that it is unremarkable
Ain't no way God isn't real. Theres no way this all randomly happened all on its own 😂😂
@@daMillenialTruckerlol OK crusader trucker...whatever.
@@daMillenialTrucker Would we be having this conversation if life evolved in the center of a star? Or on an asteroid floating in deep space between galaxies? Nope, because it's extremely unlikely to be possible there. How nuts is it that life occurred on a planet where the conditions are favorable, in the goldilocks zone. On a planet with this much water. With a sufficient magnetic field to protect from cosmic rays and solar ejecta. With a gas gas giant stabilizing the asteroid belt to slow accretion to the degree Jupiter has. It's not nuts at all. You and I are living in the place where that happened.
@@skengasaurus did you know they even found water under the crust of the earth? It's literally 400 miles below earths crust lol WHAT IS EVEN GOING ON!!! 😂😂😂😂
@@skengasaurus it's a whole ocean under the earths crust
My argument is still that the problem with the Fermi Paradox isn't how common life is, but how can we detect it? If our best means of detecting exoplanets and exomoons is watching for a dip in luminosity in its star, how exactly are we going to figure out that life exists there? If a planet is 200 million light years away and evolved life 100 million years ago, how could we possibly ever detect it? Yeah, we look for radio signals, but how do we know aliens would even use radio, or communicate via sound in the first place? What if aliens evolved a system of visual or written communication only? What if they communicate via chemical signals, like many microbes do on Earth?
That's really my problem with all of these equations, we are operating on the assumption that intelligent alien life would look something like us, but there could be any number of hidden variables changing things. I simply can't accept that Earth is the most unique planet in the entire universe, that sounds like hubris to me. The probability that life does exist but we don't currently have the technology required to detect it seems much higher to me. Call that wishful thinking if you want.
To be fair, as David has pointed out many times, there really are two variants of the Fermi Paradox. What he calls the "weak" Fermi paradox is why we haven't observed aliens. What he calls the "strong" Fermi paradox is why aliens aren't here among us right now. That is also the variant that Fermi himself was originally referring to. Why the Earth isn't an alien colony. There has been plenty of time for expansionist aliens to colonize the entire galaxy, and it seems very unlikely we wouldn't be aware of it if Earth was currently an alien colony.
There are a range of chemicals not produced naturally that we could snoop in an Exo Atmo. That's strong evidence for intelligent life.
But I agree with you. There are hundreds of different amino acids yet all life uses the same 21. What if life evolved using a different suite? It might turn out radically different.
That last sentence you wrote about the probability seeming higher to you is a fallacy though, that’s just a total guess that feels more right to you, but has no mathematical backing
I think we would notice if aliens had colonized Earth and were living here. We would also notice if aliens had started building Dyson swarms around all the stars, or were tearing them apart for materials. In fact we probably wouldn't exist in both scenarios. That is the Fermi paradox.
There has to be a rate of life. There is no reason that number can't be incredibly small. Like one in a trillion, or one in a trillion trillion. The fact life exists on Earth gives us 0 information. If life didn't exist here, we wouldn't be here to observe it.
@@Erikaaaaaaaaaaaaa - so we are talking about rare in the galaxy not rare in the universe
I love these videos. They teach me so much. And I love the way that the information is presented. Thank you my friend.
"They did the math!" Love it. But my "believer" side always goes back to the quote from Contact.. "It would be a big waste of space!"
What if that “sterilizing impact” was a necessary precondition for life to emerge ?
Indeed! Rare Earth hypothesis believes so
@@CoolWorldsLab - I can't think of any reason why a sterilising impact would be necessary. Indeed if life was not present then I don't see what sterilisation means!
@@sja45uk I will posit that i am a creationist so it's not my forte (yeah i know, creationist in a evolution topic), but one of the major ideas for how life could have been sparked seems to usually require intense heat events, a lightining strike, volcanic vents etc, there's no reason to think a impact event wouldn't be able to do that as well, especially if there are ways for elements to form we haven't discovered yet, for example, earth is a rare planet with phosphorus, there's no guarantee that phosphorus or some other element could form under the rare conditions of a sterilization event impact, as it's unlikely we'll be able to even test those conditions for a long time what would happen in such of a event is only something we can make educated guesses on..
@@tatsuya2112 life did not "spark" into existence spontaneously, it slowly arose over millions of years from increasingly simpler chemical systems.
Aside the moon forming impact, the later impacts I believe were much much smaller mass so minimal Earth chemistry changes
Great video. But isn't there still one factor you haven't addressed that could kill the theory? Namely, the likelihood of abiogensis. It is entirely possible that abiogensis is so incredibly unlikely that it literally never happens, except here on earth. And since we don't even know, really, anything about abiogenesis, we cannot possibly discuss its likelihood. The only stance we can take is one of utter agnosticism.
This is entirely what this video is about.
The likelihood of abiogenesis is precisely 100%.
OP is obviously talking about the probability per planet. It's only 100% if we're talking about the universe rate.
I think it is a fair point that 72 years after the Miller-Urey experiments chemists still don't have a plausible model for abiogenesis. If it is easy someone ought to be able to replicate it.
@@someguy999 Obviously. And that makes the OP's post contentless and wholly uninteresting. Film at eleven.
I think what you've done is just rule out life around F type stars, which we kind of suspected anyway. But you also don't rule in K type stars which give around 10 times more time than G types.
Also one of the great filters would be Eukaryotic life. It may be that 3bn years of Prokaryotic life could be anything from at the earliest, an average or a latest event before the first Eukaryote.
I agree he's always trying to prove life is super rare and we're the only intelligent beings in the galaxy total rubbish
Who knows whether or not the eukaryotic/prokaryotic distinction would even apply to non-earth life
@@moshpitjo1146 isactly
Another assumption is that evolution would typically take so long before sparking into complexity. What if some environments push evolution hard so it has to adapt a lot and often? Between the two assumptions and the sheer number of chances out there, I think life, even intelligence, might still be common enough. I did find his point on the window that life has to do these things very eye opening when I first ran across it, and while his point does lean on our experience alone since that's all we have, it could be valid enough to reduce many chances across the galaxy.
@@rhaedas9085 totally agree if it was a random event then we could be the unlucky ones. Maybe 100million years is normal for the leap on other planets
It's hard to get passed the weak anthropic effect, where the odds of life occurring on a planet where the occupants want to know what the odds are, is 100%. This is interesting and thoughtful work, ideas rather than facts though.
Thank you for explaining things like this in an easy to understand way.
Your video are always informative but this one kind of blew my mind. Thank for presenting it in a way that that I can understand it.
Europa Clipper will change everything.
I sincerely hope so too. If there's 'anything' that seems 'living' would indeed *change everything.* My gosh, what a tremendous finding. But then again if not, that's fine. It pushes back the hope of finding something back a bit. I really appreciate his approach to this subject. He holds reservations about finding something as if, it's gonna happen every time and every place. I'm in the same camp. Looking close into the actual mechanics that would enable life to start. All very fascinating to me.
i really don't think so, but still an interesting and important mission.
I doubt it will change everything, but it is the most exciting opportunity in decades since the first proper samplings of the Martian soil!
highly doubt it
I hope it does not. I would love it if there is life on other planets, but it would be best for us if there is no life in the solar system even a basic one. That way we will be able to expand and use the resources of the solar system to prolong life on Earth, including sentient intelligent life. Clearly, we could be gravy Aliens and just go to Europe and exploit the water and use the same reasoning used for abortion (even better because it won't be a clump of cells) but it will be divisive. Also as the activity of the Sun increases we may need to move.
Note that Stromatolites are fairly advanced lifeforms that have developed the ability to glue themselves in place and have everything they need for survival delivered to them.
Yes, it's a hint that life might not originate from Earth. Panspermia might actually be a thing.
@@julien5053with 3.5+ billion years of evolution, they should be advanced. Not sure how thats evidence of panspermia.
@@TheEljefe20 re-watch the video, there is something you missed
Prof. Kipping, if indeed we have about 900 mil years left, surely there's enough time for you to make a video/podcast about Quasars and Magnetars, right? 🙃
He needs more mass before broaching the topic.
It means the world to hear that you enjoy the content and especially the narration. Putting heart into every word is what makes it all worthwhile.
I do not think there is enough negative bias being applied to our thinking, regards the exacting balance required for evolutionary presure, to much pressure and evolution fails, to little pressure and it fails...that sort of puts the odds against evolved life in the universe up a considerable amount.
That early collision is now under question.
The early collision hypothesis is the only way we come up with a large moon like we have. The likelihood of a Planet having a moon as large as ours is extremely unlikely for many reasons.
@@georgespalding7640 The likelihood of a planet having a moon as large as ours is 100%.
@@altus3278 The likelihood of a planet having a moon as large as ours is 100% *given we've seen it in reality*. Bayesian statistics gets you like that.
@@georgespalding7640 did you see the research tha moon rock is so close to identical to Earth that it puts the collision in question
@@georgespalding7640 pretty sure, the moon also has like a similar composition to "earth rock" aswell almost like it's a chunk of the planet that consolidated.
You have to also remember that life on Earth had some setbacks that, while common, aren't necessarily ubiquitous. We can likely assume a nonzero number of atmospheric changes similar to Earth's oxygenation event, which caused mass extinction; but things like asteroids and other natural disasters are all up to chance.
I think that's an important point - For example, the Earth was in an evolutionary stall for about a billion years. How does that affect the numbers? Also, there have been several extinction events, how many of those were outliers? All of them? None of them? We only have one example. So timelines and some clever analysis gives us very little idea of how common life is in the universe - apart from the basic fact that some kind of life started fairly soon after it could.
Aerospace Engineer here: In the last couple of years I have gotten into economics for the simple reason that economists are interfering in engineering to a staggering level, which is why we have an energy crisis, but that's another story. In looking into another profession and how it trains people you not only get to examine that profession but re-examine your own and we don't do that enough.
One of the great flaws in economics is the lack of self-evaluation.
They have an awful lot of theory and modelling that has NEVER been truly tested except on US and right now that's looking like very bad outcomes as they keep telling us all is well and that's not going to end well for any of us.
Your profession is in a similar predicament except you are NOT costing several billion people a future like economists are. HOWEVER, what you and you colleagues are doing is modelling based on UNTESTED THEORY. Yes this is all very interesting and I like your channel because it expands my own knowledge base, but you need to temper this will reality and let people know these are theories that are UNTESTABLE because of the time frames involved. They are some every interesting theories and models but they are just that - theories and models.
*PLUS* and I can't emphasise this enough with dating technologies whether its carbon dating or any other dating. CALIBRATING your measurement system is almost impossible beyond a few 1,000 years because where's the actual sample that you know for certain what its age is that you can use to calibrate against. Your calibration for longer time periods is theory not measured reality.
*You are one of the very few sciences that is allowed to get away with this lack of calibration but then we also understand that calibrating such systems is almost impossible.* So you get some slack on this, but please DO NOT MISTAKE that other STEM fields are unaware of this.
Radio active decay is quite a well studied process and we don't expect it to disobey the established models of nuclear science. Decay models are derived from Quantum mechanics which is one of our most precisely tested theories.....what is the objection here?
@@kanishkchaturvedi1745 *I KNOW THAT*
And if you bothered to READ what I have said that is the problem.
Do you know that when they carbon dated the Shroud of Turin they used the 3 best labs they available and the results varied by 10% at 1,000 years age.
If radioactive dating is so damn accurate and so well understood then how do 3 top labs have that much variation?
ALL measuring techniques have limits to their accuracy which is why calibration is so incredibly important to understand. Metrology (the science of measuring) is one of the least understood fields of science and yet its one of the most important.
But trying to explain that to IGN0RANT M0R0NS is hard.
What we as humans define as life may not be a complete definition.
How do we know that life that developed here wasn't just a 'slow starter', and other intelligent life hasn't/hadn't developed MUCH faster than we did here on earth?
What I never understand is;
If we all have one common ancestor, such has been proven.
Then this means life has only begun once in 4.5 billion years. Evidently making it extremely rare! Surely answering the Fermi paradox.
Perhaps life has emerged multiple times, but the first life to emerge always outcompeted later life because of greater efficiency and differentiation
We have two - at some point mitochondria were taken into single cells as a symbiotic relationship, although the details are still debated on. If we had two at one point, there could have been more that simply didn't survive later changes. Once life became prevalent its activities would make further chemical replicators nearly impossible due to competition. Life on a blank canvas may start early and often. We only have one example so far to work with.
There was an emergence of life on earth before us. Look up the Ediacaran geological period. It was about 630 million years back. All we have are the fossils but it's pretty wild
If the existence of life prevents newly formed life from gaining a foothold, then abiogenesis could happen every 10 million years, but every time after the first time, it would get eaten immediately.
No, life could've started many times. For all we know, it keeps starting all the time, just never gets anywhere and disappears before we discover it. Also, life eradictes life and traces of life. On our planet, there's also geological "life" that complicates things.
"the universe is teeming with life" needs qualification I think, due to the mind-boggling scale of the universe. If the observable universe has 2 trillion galaxies, and each galaxy has one planet hosting life, then you could say there are 2 trillion inhabited planets. That sounds a lot, but because the universe is so huge, the chances of travelling between galaxies is about zero. So the universe could have a vast amount of life on a numeric basis, but the inhabitants of each inhabited planet will likely never encounter another inhabited planet, because the density of life is so very low.
Of course, if life does start early and often, it begs the question : why have we not detected any other advanced civilizations?
Just like travel to any of these places communication is also basically impossible convinced that you're right though at least half a trillion
The density could be MUCH higher, and we still couldn't detect them (currently, possibly ever)
Make the following assumptions:
We advance to the point that interplanetary voyages (and limited (or maybe even "moderate") resource use within our own solar system) is possible but hard/expensive/not economically worth doing on an extremely large scale (maybe mining asteroids etc, but not a fundamental change to the point where much of humanity lives off of earth in a dyson sphere)
Voyages to other stars are "possible", but not really very viable other than for scientific curiosity (with fairly limited returns, incredibly long time periods (significantly sub-c))
And those voyages could be at most equivalent to the apollo program (a one off (or a few) overall insignificant "visits" to the nearest possible destinations) but anything beyond that is just too demanding with too few scientific returns for the effort expended.
Barring fundamental changes to physics, this is what I would consider "likely" as the apex of what is possible.
Say we don't wipe ourselves out, and exist at that technological level for even many millions of years.
How far apart could two such civilizations detect each other.
Only a few dozen light years, and then you run into the problem of radio (or any other) signals getting lost in the noise.
There could be dozens, even hundreds of such civilizations in our own galaxy, and they could never detect each other.
Space is just too vast, and even the nearest star systems are just too far away.
We live on an island on a vast ocean.
We can see some other islands in the far distance, and even take our best guesses about what exists on those islands ... but they are just too far away to reach on the treacherous seas.
We hypothesize about the existence of other civilizations on those islands, but are far to far apart to see the smoke or light from their cooking fires, and we'll never know.
That's my assumption about the Fermi paradox.
@@missyandmartinbakalorz1725 Interesting comment. I would expect that the density of simple life is much higher, and follows some sort of "long tail" distribution. So in our galaxy there might be a billion planets with single-celled life, a million with multi-celled life, and ~1000 with advanced life, like primates. Then advanced technological civs that can be persist for a significant time might be 1/1000 of those...
A billion planets with life sounds a lot, but there may be 3 trillion planets in the galaxy.
No one knows anything. That is certain.
This is the only truth.
Well we know lots of things but when you learn one thing there's more things to learn. That's more accurate if you know nothing there's nothing to learn. 😅
And how do you know this knowledge?
How do you know that?
@@poirob2Becouse we are just guessing
Microbial or non-civilizational complex life fascinates me. The Hart-Tipler conjecture is pretty convincing to me though.
I enjoy all of these videos but this one just went over my head.
Requires a rewatch.
5:10 Abiogenesis has to be the most common occurence in the universe. My spouse is adamant it takes place even in completely closed off sterile systems the moment you take your eyes off of them. For example, if you forget to put away the milk cartons to the fridge the nanosecond you come home from the store, they are apparently immediately teeming with life and need to be thrown away.
That is not abiogenesis. Abiogenesis is life coming from inorganic molecules. If you had pure chemicals in a sterile container, life arising from that would be the first documented ocurrance. There are pre-existing microbes even in pasturized milk
@@ungmd21 it was a joke, my friend.
She's not wrong, but that's because life is already present. If you mix vodka with a juice of some kind to an ABV of 9% and leave the container open, you'll get a nice vinegar just from bacteria in the air. Or if you leave the juice out on the balkony, you'll probably get a wine. Life is fascinating.
jokes not allowed here. it is a science channel 😉
@@bbcc-p7w :)
Suggesting there is no other life in the universe is like pulling a drop of water out of the ocean, not finding any life and then claiming there is no life in the ocean.
I am willing to believe that there exists life outside our planet, but your analogy is grossly incorrect for several reasons.
The main reason is that in any drop of ocean water... you would actually always find life! Bacteria, phytoplankton, zooplankton, protozoa and algae, and even marine viruses (that one could dismiss as "not alive", although discovering a virus on Mars would probably be equated to discovering life...), you name it.
Another reason is that we are in the exact opposite situation compared to your analogy: we have one example of a planet with life, and we want to extrapolate to the other planets/moons of our solar system, our galaxy, or other galaxies to infer if they may host life.
Next time you find an ant in your bed, ask yourself if your bed is full of ants! 😁
Cool quote whose is it?
@@No_Camping You are correct. timelapsega should have said fish instead of life.
Thief
Thanks to GroundNews for supporting this episode! Head to ground.news/CoolWorlds to save 40% on the Ground News unlimited access Vantage plan with my link. Let me know if you think Earth-like conditions are common or rare, how special do you think we are??
This video seems to go against your paper 'An objective Bayesian analysis of life's early start and our late arrival'. We are orbiting around a third generations star. There has been a ton of time and space for life to develop into civilizations if life is easy to form, yet we seem to be alone.
Ground News is a good sponsor. I like them. I use them. Good information -- good information _sourcing_ -- is essential for being a participant in democratic society.
Satellites, Jupiters, etc is one thing. Phosphorus (or lack thereof) is quite another in my view, and often overlooked.
@@Nethershaw I wish Ground News would allow you to specify your own bias distribution of the various sources. I don't agree with some of its defaults.
@@TheVigilante2000no it uses the results of that paper! You highlight lack of intelligent civs, which is fair but a different process to abiogenesis (which this video concerns)
One factor to consider in these kinds of analyses if applied to all potential alien biospheres is that the CO2 and temperature constraints on photosynthesis and plant life on Earth need not be universal. Alien lifeforms could potentially evolve other forms of photosynthesis that have different limitations. There is also the possibility that an intelligent civilization could arise from a biosphere that never evolves oxygenic photosynthesis and instead ends up with some other process for primary biomass production.
Love seeing someone open to revising their beliefs based on science!
That's the short definition of a scientist.
I've heard rumours that there's a Varga-like Planet that could possibly have microbial, non-intelligent life. The planet is called Earth 🌎
I doubt a non-intelligent life form would be able to type that.
That gets 4 "ha"'s from me. 😊
Oh don't be silly, everyone knows there's way too much free oxygen for life to exist with that planet's atmosphere.
that's odd, it's called just like us 🙃
@@SirThanksalot_1 Oh wow, do you have intelligent lifeforms? If so, can we have some? We're running out.
Given perfect conditions the genesis of life may be easy, but I still think that the likelihood of perfect Earthlike conditions are prohibitively rare. SO much had to go perfectly for the Earth to be where it's at right now and to be so protected from constant asteroid bombardment, and to have a sun that wasn't too deadly for the ecosystem, as well as not too close to any stellar killers like supernovae or gamma ray bursts, and there had to be enough asteroid bombardment to deposit enough water onto the planet to support the development of life, and the planet had to be big enough to keep enough of an atmosphere but not too much, and the tilt had to be good enough to allow for a proper water cycle, and so on ad infinitum. Earth, is just super, incredibly, rare.
We have no idea if any of this is significant, required, or rare, or if we're just retroactively finding connections, as our pattern-seeking brains always clamor to do. As David says in this very video.
We have to live on *a* planet that supports life, but that doesn't mean there's any special significance to how that planet is. It's like assuming only white people can win the lottery because the one lottery winner you've encountered is white. Well, they can only have one skin color. Doesn't mean there's any significance to what skin color that is.
All Earth's configuration tells us is that this configuration does support life. It says nothing about whether this configuration is required, and definitely not whether it's rare.
I know that many would not want to talk about supernatural factors but has anyone also considered the fact that besides life on this planet, we have the perfect conditions for PERFECT total solar eclipses? I ask anyone to calculate the odds of that occurring anywhere else in the universe of 200 sextillion stars
@@Erikaaaaaaaaaaaaa You need to pay more attention to Organic Chemistry. The complexity needed for life requires Carbon Chemistry, and the environments where Carbon Chemistry can dominate are extremely limited. Liquid water, no ionizing radiation, stable temperature range, etc, etc. All of these variables must be maintained for Billions of years. It's just the science.
"Incredible rare", well, nobody knows how rare. But it's not unreasonable to suspect pretty rare and yes, maybe indeed incredible rare.
What we dó have a reasonable estimation of is the amount of planets in the known universe. An INCREDIBLE amount.
Soooo.....
@@ksh95 We have absolutely no idea that carbon chemistry is required for life.
For example Gerald Feinberg and Robert Shapiro have shown how one could use a system of magnetized particles as an alternative to DNA. In other words, we don't even know for sure that *biology* is required.
You are building your entire thesis on a series of unproven assumptions. You might be right, but just like OP there is no way to know whether you're retroactively finding patterns where there are none or whether you're actually onto something.
I might be an idiot Bioinformatician, but I’ve never understood how alien theorists make statistical claims with a sample size of 1
Simply put a sample of one data point is a data point. It is information. If we had a sample of zero, no inference would be possible. Nothing magic happens in going from 1 to 2 data points, but something does change from no info to some!
But... With one data point there's no way to tell anything about the actual population. Like, the one data point looks the same whether deviation is massive or minimal, and outliers look identical to data points that are representative. I'm not sure the magic is much greater from 0 to 1 than from 1 to 2.
But I'm also an idiot with a Com degree so... I'm hoping some 3Blue1Brown crossover fans can come explain the math.
Ha! There you have a point. As long as we do not see (physically!) any other planet with a biosphere, we cannot set our own data point. All we have are planets (lots of them) from which we can tell „no life“. It is like guiding a caravan in the desert to the next oasis by just following the „No Water Here!“ signs. And basically that is the root problem of the Fermi paradox.
It's possible to do probability with a single data point (for example, estimating how many tanks the enemy has by retrieving a single serial number), it's just that you shouldn't expect much precission.
@@CoolWorldsLab Really? I thought that going from 1 data point to 2 data points is more significant. I am no expert, but my reasoning has been that if we have only one data point,the odds of life could be anywhere from 1/(10^1000), which is basically zero with the exception of our own planet, to 1, which means every planet has life. But if we add another data point, suddenly our chances skyrocket. Now I am reconsidering this.
Thank you Prof. Kipping for this amazing video and sharing your knowledge with us. I am extreamly excited about the results from JWT.
“We will show them Our signs in the horizons and within themselves until it becomes clear to them that it is the truth. Is it not enough that your Lord is a witness over all things?” Quran 41:53
"Garbage in, garbage out." All religion.