The Edge of the Universe
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- เผยแพร่เมื่อ 2 ต.ค. 2024
- The Universe is immense. Does it have an edge out beyond the Cosmological Event Horizon? Or in time, before the Big Bang? Or in higher dimensions like Hyperspace?
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Credits:
The Edge of the Universe
Science & Futurism with Isaac Arthur
Episode 305, August 26, 2021
Written, Produced & Narrated by Isaac Arthur
Editors:
A.T. Long
Keith Blockus
Cover Art:
Jakub Grygier www.artstation...
Music Courtesy of Epidemic Sound epidemicsound.c...
![Beyond the Observable Universe [4K]](http://i.ytimg.com/vi/mty0srmLhTk/mqdefault.jpg)
![ลองสั่งของจากแอพ temu ถูกจริงหรอ?? [โกงไหมครับ ep.88 ] | DOM](http://i.ytimg.com/vi/RTcZSQTiDZw/mqdefault.jpg)
"...,at least until we discover how to walk at right angles to reality." Superbly original way of putting that notion forth.
I believe "perpendicular to reality" was a line from Hitchhiker's Guide. Potentially intentional.
Had an interesting idea for a scifi novel on how to access that. How about streching space out alot and hoping that some fluctuation makes wave like things that ate right angle dimensioon
This episode has a retro Isaac Arthur feel. Like I've travelled a few years back in time.
Maybe it’s the audiob
Semi-intentional, the FTL series is one of our first and this is technically episode #6 of it, and I used some of the same visuals and music themes, though mostly without thinking about it :)
Or maybe it was sent from the past...!
You sure you haven't?
I prefer the old IA videos more of a storyteller feel to them
A fucking big rain hit our camp so nobody wants to leave the barrack, even the guys who are already on leave right now, what a good time for some SFIA!
Nothing worse than marching in the rain :)
The first rule of Warfare: Stay dry and always carry a towel.
@@SpecialEDy First Rule of Hitchhiking: Always know where your towel is.
I'm a primary school teacher in the Netherlands and currently teach ~8 yr olds. I've brought my pc to run SpaceEngine a couple times and show them around. They come with a million questions and even after answering them for over an hour, they want more.
It's thanks to you that I have a lot to share as well. Thank you so much for this!
You're an awesome teacher. I knew I would have killed to have something like SpaceEngine to see back in the day
An absolutely wonderful channel with such astoundingly mind stimulating content. Thank you Issac, keep up the great work.
"We're not bothered by kicking the can down the road in science so long as the can arrives where it's supposed to be, which for a lot of theories is apparently a recycling center." 🤣🤣 And lots of episodes in September. See you Sunday!
TH-cam - There's a new Isaac Arthur video. Me - Immediately stop what I'm doing to watch
your channel is great too.
Fun fact - Isaac was a massive inspiration for me to start my own channel
@@HistoryTime great to hear that. always nice to see an domino effect of great stuff.
Sad to hear about your surgery patient that died because he posted a new vid 😢
Watching this with my 2 and 4 year old sons. They love watching your videos, the visuals are captivating for them and they ask me lots of questions about what you’re talking about. Thanks Isaac…I hope we can all maintain our sense of wonder like my kids have right now.
I bet your 2 and 4 year olds would actually prefer Peppa Pig !
@@ohmatron8360 haha nope. They’re familiar with that show. They ask to see “space videos”
@@roadkillanonymous4807 I was only pulling your leg...I think it's great you open your children's minds with vids like this.
Isn't the vocabulary a bit too much for children?
Anyway, it's great if they enjoy it!
@@tite93 of course it is. They like the pictures of space and ask me what he’s talking about. I do my best to explain it to them, no doubt they don’t really get it yet.
Happy Arthursday fellow sapient intelligences! Greetings from the Quantum Chimichanga Reality!
Yum
Hello from the Quantum Cheeseburger Reality!
Hello from the quantum cigarette reality
*Teleports in*
Greetings, fellow multiversal voyager!
*Rubs tentacles against your thigh*
A happy Arthursday indeed!
*Farts cinamon tasting cloud of joy*
@@askani21 wtf bro
This is exactly the type of show that made me fall in love back when I found this program!
Most physicists:
It can't be explained in words, you need to know the math.
Isaac Arthur:
Grab a snack and a drink; we're talking physics.
The edge of the universe is where we can find Isaac's video about atmosphere mining
♥✞♥Jesus Christ is Lord. Hallelujah We are God's creations. He spent time and energy making us each unique and are all beautiful in His eyes. Choose what to do with your body wisely, because the Lord expended effort on it. Do not throw it away. Cherish the beautiful gifts that you have been given. Thanks be to God.♥✞♥✞♥
Wow! Early enough to see the edge of the universe from here!
Cheers Isaac! Another great topic
♥✞♥Jesus Christ is Lord. Hallelujah We are God's creations. He spent time and energy making us each unique and are all beautiful in His eyes. Choose what to do with your body wisely, because the Lord expended effort on it. Do not throw it away. Cherish the beautiful gifts that you have been given. Thanks be to God.♥✞♥✞♥
The Edge of the Universe has a wall, and on the wall there is a legend, it reads:
*SLOW, Spaced Out Hippies Ahead!*
We all know there's a brick wall with a tourist view finder at the edge of the universe where you can look at the other side & find a universe where everyone wears cowboy clothes & hats. That's what Futurama taught me at least.
So excited for this. I remember being 4 years old, and trying to wrestle with the concept of “the end of space”. How does it end? A wall? Then what’s on the other side. I think that kickstarted my fascination with space
My current running possibilities are that either you hit a wall, you leave the universe and enter nothing, or it turns you like the inside of a black hole would.
@@gigastrike2 It’s still so incomprehensible to me. There’s no theory that doesn’t sound utterly insane.
It could also be round, just in 4th dimension. Similarly like on Earth - surface seems 2-dimensionally flat, but there is no wall at the horizon - it just keeps on going until you go around and reach your starting point
@@krumuvecis like a game of asteroids.
Pretty impressive for 4
This reminds me of a throw away sentence in Arthur C Clarke's novel "Against the Fall of Night" where its casually mentioned that the ancients had taken a starship and raced around the rim of the universe in a single day.
Everyone only went to the universe to see them him the edge
13:24 I, for one, welcome our new hyper dimensional cat overlords
You know all those yet unexplained phenomena in the universe? These are all caused by the Hyperkitten pawing at our universe while playing with it.
That's a lot of talk about edging. Interesting talk as always, Isaac!
lmfao
His videos are always edgy
I'm edging as I'm reading your comment. And now I have arrived all over the place.
I do think I've seen that compacted universe hung on a collar a cat was wearing and it's slightly bigger brother in the work locker you "don't open unless emergency"....🤫😉
✌️ Favour ALL, Isaac Sarah
A cat in a morgue??
@@davidfinley1214 Not in our version of the collapse of the wave function.
Economists: "There is no free lunch"
Non-Economists: The whole universe is a free lunch.
Physics: "Matter can't be created or destroyed."
Non-Physicist: "Tell me this again after teaching me about big-bang theory."
Wouldn't physics say: Matter is energy?
The Universe is a free lunch that requires effort to gather. This effort is the cost of lunch.
@@kedrednael Yeah, that's weird. Every physicist knows that matter can very well be destroyed into energy or created from it.
@@InventiveHarvest The effort will also increase entropy.
@@johannageisel5390 Hmm, I suppose you could say Entropy is like a tax; you get nothing for paying it, you can't avoid paying it, and the asshole who set the rate doesn't listen to his constituents but swears it'll be better in the next term.
Seeing more often less than 30min vids on SFIA is super worrying for me.
10-20min videos on TH-cam will become the normal.
I have to wonder sometimes if we don't have the whole idea wrong? Kind of like a puzzle where the pieces mostly fit, but the picture makes no sense.
Indeed. First off, there might be some event or interaction, that has passed by our possbility to ever detect it. Like how in billions of years, there wil only be "island galaxies" left, and whatever intelligence arises then, will not be able to find all the pieces of the puzzle so to speak.
Our minds have certainly not evolved to understand the intricasies of the universe, and I dont mean intelligence here, but rather how we are experiencing and viewing the world thorugh the lense of a specific homonid species. With all that entails concerning limited capabilities, brain unable to think in a way that could give us an understanding, our conecpts of sensors and measuring being limited, etc.
And ofc the most important issue; "is math discovered or created?". Because there is a possibility that math and our understanding of the unvierse is just a really well functioning framwork/lense to view the world though, without actually being an intrinsic part of the universe as our current understanding/hope is.
Personally I have hope that we might someday be able to understand what this existence really is, if it even is a "concept"/"occuring event" that CAN be understood. But my best guess is that we as a species will have become something entirely different looong before we will ever get close to this point. In the meantime I love learning about this stuff, and hope us strange little apes can argue, discuss and intensely try to figure out what this all really is about :)
For that part about math, Roger Penrose has some interesting videos and interviews about this subject, if you did not know about it or want to check it out :)
Can you revisit active support structures again and go into more details about how they can be achieved? Your original video is one of the only few web sources on this. And as active support appears to be the basis for all mega structures and major space construction concepts I feel like this deserves a remake.
Thank you for all you do. Please upvote so Isaac reads this! Ty all!
You might find more sources by searching the names "space fountain" and "orbital ring". "Active support structure" might be too vague to get good search results.
en.m.wikipedia.org/wiki/Space_fountain
en.m.wikipedia.org/wiki/Orbital_ring
There is something different about the vibe of this video. There's a strange outburst of confidence and witty... humor? humor-adjacent thing that isn't present in the older ones. Especially at the beginning
I like this video
The last time I was this early, the temperature of the universe was 10 billion Kelvins
I find it humbling that we laugh at people in the past who thought they would fall off the edge of the world, and yet here we are wondering the same kinds of questions.
Gold.
We will hopefully never reach the end of your videos! Thanks for your hard work!
♥✞♥Jesus Christ is Lord. Hallelujah We are God's creations. He spent time and energy making us each unique and are all beautiful in His eyes. Choose what to do with your body wisely, because the Lord expended effort on it. Do not throw it away. Cherish the beautiful gifts that you have been given. Thanks be to God.♥✞♥✞♥
2:25 .......that deep sigh..... yeah.... that is pretty much how I feel all the time. The best I have ever heard it put into words is Bill Hicks.... "...bear with me while I plaster on a fake smile and plough through this shit one more time."
Origins are such difficulties.
Each personal universe -- the universe as seen from a given point -- expands in radius at 1 light-second/second. Expansion is in spacetime.
Hey, Isaac. Have you written any books that are science fiction? I feel you'd be gangsta at it.
love the futurology but I also love just learning about space and I think we should have more of thee sprinkled in.. also literally can never have enough fermi paradox vids!
♥✞♥Jesus Christ is Lord. Hallelujah We are God's creations. He spent time and energy making us each unique and are all beautiful in His eyes. Choose what to do with your body wisely, because the Lord expended effort on it. Do not throw it away. Cherish the beautiful gifts that you have been given. Thanks be to God.♥✞♥✞♥
Nothing like waking up to a new video by Isaac!👍
...we’re not bothered by kicking cans down the road in science so long as the can arrives where it is supposed to be. Which for a lot of theories is apparently the recycling center...
- Isaac Arthur
I'm relatively new to this channel but id like to say your content is really awesome
Hey Isaac, another great episode. Thanks! I was wondering if you could explain what it would take to divert very cold air from the troposphere to ocean level, for example in the Arctic? How difficult would this be? Would it actually have a significant cooling and reflect effect to mitigate some of climate changes effects in at least that region?
Thanks
There are 3 ways to watch SFIA.
1: With 100% attention, to learn something and to get thinking about the universe and our place in it.
2: As background noise, so one doesn't feel alone.
3: As relaxing podcast to fall asleep.
All 3 of them are wonderful and I enjoy every second of it. Your videos are running around 4 - 6 hours on my screens every day and I love it.
Traveling to an older, bigger, colder universe might be an interesting plot point for a sci-fi story beyond just hiding there the way you briefly mention. If you can travel back and forth between universes, you can look for evidence of dead mega-structures and such in the older universe, return to your universe or an even younger one to travel quickly to those locations, and then search for advanced technology that there literally hasn't been enough time for anyone to have developed yet in your own universe. It could make for an interesting take on the "future explorers find ancient ruins with super-powerful alien artifacts" trope.
♥✞♥Jesus Christ is Lord. Hallelujah We are God's creations. He spent time and energy making us each unique and are all beautiful in His eyes. Choose what to do with your body wisely, because the Lord expended effort on it. Do not throw it away. Cherish the beautiful gifts that you have been given. Thanks be to God.♥✞♥✞♥
I would say if someone asked where the universe is expanding into, just let them imagine the surface of an inflating balloon with a stickfigure on it.
The universe isn't expanding anywhere, it's expanding onitself.
If you take it down a dimension with a stickfigure, people can grasp the theory better.
The question is it that edge has drinks and snacks.
Lee Smolin had a theory that black holes formed new universes with slightly different physics. As such, one prediction is that universes should be tuned to making more black holes.
Yeah, and it seems like a really interesting theory(especially considering our universe in particular, has attributes that makes it an almost ideal blak hole "spawner") but it is part of the many worlds theory. Ofc, both could be true. And if our universe has other variants/temporal states we can cross into/use as a medium, and there is a hyperspace above that again. I would say then that the possibilities of many worlds is almost 100%.
The really cool thing I think, if any of these cases are true. Is that with our universe being such a damn good black hole creator, we might end up being like the central travel point/nexus for travel across both our other temporal variants and the multiverse, sometime waaaaay off in the distant future. That would be neat :)
I tend to subscribe to the idea that time-space is plotted out on the inside or outside of a spherical shape. This allows for a foundation of infinity, being as there are infinite coordination points on a sphere.
Of course, this might mean we're all trapped on an event horizon...
What if the real edges of the universe were the friends we made along the way?
Explain please.
How is it possible to make such stellar ( höhö ) content and drop it with this frequency? Does Arthur live next to a black hole to find the weeks of production time to drop these almost daily?
he has a decent backlog & writes these eps weeks or months in advance.
We already jump dimensions. Your perception is the only thing in motion, through time. Reality is that stack of paper, or maybe slides, composed of parallel dimensions. Your perception moves from a fixed point on one slide, to an adjacent point, on the next slide, in what seems to be a single direction. Something in the structure of the mammalian brain, another sense perhaps, allows it to perceive this motion. This makes it possible to choose, the next point; or at least, present the illusion of choice.
Great to see the Matt O'Dowd shoutout at the end. PBS Spacetime is up there with 3blue1brown and Michael Penn as my favorite science content creators (the latter two being math oriented, PBS physics)
The opening phrase of this video is my favorite quote to all those that like to play smart by parroting "nothing moves faster then light"! =))
@@fantasyEXX No they did not.
You put History and Discovery channel to shame, lol.
"We're not opposed to kicking cans in science, as long as that can arrives where it's supposed to be, which apparently to some theories is a recycling center."
I like this
Last time I was this early, there was one
unified force.
So...internally, the travel time for a photon is 'zero' regardless of the distance (or how much time passes for some observer). What happens if the travel distance is literally infinite though, due to there being nothing to interact with? An infinite travel time from an external perspective, and yet still instantaneous internally?
16:54 Make sure the young and hot universe you try to get into is at least 18 y/o or Chris Hansen ask you to sit on a chair.
So what happens during a possible Big Crunch? Would galaxies begin to wink into existence at the observable horizon, speeding towards us faster than the speed of light? As the universe got smaller, could we reach a place where we could go no father (some maximum distance from our starting point) and we would start heading back regardless of the direction we chose? Would black holes grow bigger as they merged and swallowed other converging matter, our would they get smaller as the space that they were embedded in contracted? It would be interesting to see if CPT symmetry really would be conserved in such a scenario ;)
Yes
Kind of - we don't really know what happens in a singularity due to divide by zero errors.
Black holes are weird, the singularity gets smaller as it adds mass, while the event horizon gets bigger.
Liked the tone and cadence with this one. Felt more personal, like listening to a friend
Nothing can travel faster than light.
Nothing, can travel faster than light.
Both are true statements
If you think about it, there is no contradiction between energy conservation and energy coming into existence at a beginning of time. Conservation of Energy is just an implication of time invariance. If there's no such thing as time, there's no time symmetry, and no such thing as energy conservation. It's not that energy goes from a zero to non zero quantity at the big bang. It's more like energy goes from a null, undefined quantity to some actual quantity.
Also, the total energy of the universe might be zero, so coming into existence did not cause a change to the total either.
Beyond the edge of the universe is endless darkness with no wall or limit to it
Hi this is one of your best videos yet and I have really enjoyed your work over the past few years. I would like ask you about the no real images of the earth from satellites in high orbit.
That dark energy is coming from somewhere.
dude, your diction has improved markedly . . . huzzah!
time runs slower where a lot is happening. It's the system lagging.
00:00 technically, there is space generated between us and everything else... in a geometric progression in relation with the distance to... stuff
15:00 - I though that was how FTL worked in babylon 5...
great video and amazing upcoming ones, wow! thorium, human machine teaming, stealth spaceships, very delicious topics :D
Traveling backwards in time would require ordinary matter to change sign of its mass. Unfortunately negative mass hasn't been found yet.
I recently saw some simulations where space was homogeneously filled with ordinary and negative mass - with time it forms similar sponge-like structure to our filaments, galaxies and voids. Not sure what this implies - maybe dark matter is traveling backwards in time?
Are you confusing it with antimatter? A positron, for example, is sometimes thought of as a time-reversed electron. It has the same (normal) mass, but opposite charge. This symmetry is what gives rise to pair production and annihilation.
@@JohnDlugosz No, not confusing it with antimatter, but the concept is similar. In Newtonian gravity negative mass would still produce positive force to other negative mass, but if you put negative mass into Newtons 2nd law, acceleration becomes negative. That effectively acts as if time-reversed.
There is a theory called "Dark fluid" which tries to tie together dark matter and dark energy using negative mass. As far as i know it wouldn't necessarily annihilate with ordinary-mass matter, if it was only interacting within gravity.
Maybe the universe is just God's dream and it's expanding into it's "memory". The further we peer out the more creative God gets. Someday maybe we'll see ourselves looking back!
Thats very poetic, I like it.
Boltzmann brain
wouldn't my spaceship just shrink, if I went in that "past" parallel hyperspace universe?
Does anyone know what happened to hades 9? I remember Isaac talking about it a few years ago but I haven’t been able to find anything on it since.
Afaik it fizzled out?
Isn't that the realm where Satan himself is chewing on Judas, Brutus, and... Uh a third guy who isn't as famous
The phrase; "Set in stone." doesn't seem to fit with the scale of the universe.
I miss the slower-paced videos
**watching the new video while eating a very good pineapple cake**
Isaac please do a show on the existential dread of a civilisation that develops on a planet in the late universe that is passed all cosmological event horizons. Imagine an intelligent species develops in a solar system but never has the ability to see the universe. Kind of sad to think that might happen
I think they wouldnt feel dread. Quite the contrary. Look back at our civilization, we thought we were gods creation on our own world. Only when we recognized how big and ancient the universe is we slowly stopped thinking we are creatures made by god with a divine plan. A species born to late to see anything but it's own galaxy or even it's own star might feel super special.
they would still see a cosmos just a smaller one. barring the obvious modification we'll get up to, our decendants will one day be chillin in a local group-sized galaxy too & i don't see why that would bum them out. even less reason to be bummed if you evolved in that dying supergalaxy since u would never know anything different & would still have the option of colonizing whats left to meter out the available fuel as long as you could but nothing in life is guaranteed except death sure you could've been born in better times or humanity could have evolved earlier but you & we are here now i don't see how the what-ifs change anything
@@virutech32 no I mean a civilization that saw no cosmos as everything was outside its event horizon. Its unlikely but technically possible. No matter if they invented 'interstella' spaceships, they would never find or see anything. Though would they eventually compute that they don't see anything because of expansion I wonder. Otherwise what a sad existence and shows that truth is not really so important a quality since that civilization would never be allowed to know the truth
@@dermittelfinger5903 yes very true. Might be very happy thinking they are unique and alone. But if they develop past religion, they would have a difficult and painful question as to why they are in this empty expanse of nothing. Horrible!
@@sgu00dir well the only way that would happen under our current understanding is if life evolved on a rogue extragalactic exosystem somewhere in the cosmic voids. which i guess is as likely as any other place so it's not that far fetched, but again they would never know anything else so it would only be sad for you.
i mean for the majority of human existence earth was all we ever knew. sure we saw stars & the moon, but that was the realm of the gods & all that was empty anyways so it's not like this civ would be anymore "alone" than we are.
it's not like there are any ET lining up to say hi so if being alone doesn't make us sad i don't see why a civ that wouldn't have ever even contemplated there being any other option would be saddened by it.
plus they aren't alone anymore than u or i am. there's billions of other people around & not meeting ET doesn't diminish that or really matter at all until you actually do meet an ET. that's like being sad about never having met the gods. until or unless we actually do it wont matter to the majority of people.
"Compactified" is now my new favorite word. Great stuff as always, Isaac.
You should look it up to grasp its real meaning, in mathematics first, and then how physics uses it. His usage isn't exactly _wrong_ but it gives the wrong idea of what the term is actually referring to.
@@JohnDlugosz Not sure what you're on about, mate. At NO POINT did I say the usage was wrong, nor did I say I did not know its meaning.
If our galaxy was near the edge of the universe, (not including the stars in our own galaxy) would we only see galaxys in one half of the sky with just darkness in the other? Or is our universe a 3 dimensional version of the 2 dimensional surface of a sphere (that makes everywhere is the edge of the universe), so there would be galaxys all around us but the universe is expanding into a 4th dimension we cant see?
we have no clue whether the cosmos has an edge. we have no reason to think it does. though it might have curvature enough to eventually close up but if it does we don't yet have sensitive enough instruments to detect that curvature which leaves us with a very low curvature geometry. so if the cosmos is closed it is ridiculously large & anywhere we could conceivably go would be well within that. means we would always see the same things around u no matter where u went.
if the cosmos is perfectly flat & also finite for some reason we still wouldn't really have an answer to that since we don't know anything about the boundary conditions of our cosmos & couldn't reach it anways
@@virutech32 So if the universe is closed and we dont see enough curviture to measure over the span of the observable universe that would indecate that the universe is either open or it would take dozens of times the size of the observable universe just to get 1 degree of curvature let alone the other 359 degrees that would make up the whole of the universe ? Thats gargantuan in scale, surley there hasnt been enough time since the big bang to expand to that kind of scale has it? It must be a >50% chance of being open ?
Would such an edge appear black? It might be a mirror, so they would see galaxies in all directions. Or it might be a grey and white checker pattern.
There is a strange irony in the fact that us humans have a difficult time conceiving of 'the edge' of the universe, whilst simultaneously living on it and experiencing it constantly. The edge of the universe is in fact the only thing we really know. This is because we live on the edge of the time dimension, the future is outside the universe. The edge of the universe is today, and beyond the edge is tomorrow. And the expansion of the universe is not an expansion of space, but an expansion of space-time. It is actually time that we see expanding.
Very astute point! We're looking for an XYZ three dimensional edge while simultaneously riding the edge of the Temporal dimension. We can't be thinking in three dimensional geometry when there's four dimensions at play. The human brain processes Time and XYZ space as two separate things, hell physics is based around them being two separate variables (speed for instants is spatial distance over time) but their really all the same concept. It almost begs the question that perhaps we have so many problems with the math in physics b/c we started on the core assumption that space and time were independent variable and not just different directions of the same variable. How would the math change if we threw out the separation and treated them as up-vs-down rather than separate entities?
@@Lusa_Iceheart well look no further than Einstein himself for the maths of space time! But I do sometime wonder if the expansion of the universe, of spacetime, is in the main the expansion of the time dimension. Its strangely intuitive if you think about it, every passing moment is that expansion.
@@sgu00dir Oh jeez, I like to think I can handle complicated topics, but Einstein was a whole different level! I'm not sure I could follow along with his math. I can however appreciate the work other people put into understanding it all. Yes, it does seem to be pretty intuitive, the answer right there, time is expanding so spacetime is expanding, it makes sense.
I always wondered that if you were to hypothetically travel faster than the universe was expanding, what exactly would you go into?
I would guess just more universe, at least to a point. I’d say it’s doubtful that we are at the exact centre of the universe.
You mean like ordinary motion? The expansion is quite slow at short distances, and zero in gravitationally bound systems like our solar system. We travel from A to B faster than the expansion of the space between A and B all the time! It's a requirement of actually getting to B.
@@JohnDlugosz assume for a moment that we have hypothetically teleported to the very furthest edge of the universe. It is expanding, but into what? Assume we cross the boundaries between what is the universe and what it is expanding into. Is it a wall preventing us from going further than what has already been defined as reality? Or is it as of yet unknown and/or incomprehensible area beyond what we know as our universe?
I hear Isaac Arthur released an edgy video today
If you gain mass as yo approach the speed of light, how much do the galaxies at the edge of the universe mass? Assuming those galaxies are indeed traveling FTL...
They're not moving at the speed of light, they space they are in is.
@@TheEvilmooseofdoom but space has no mass - therefor space cannot move. But space has energy and energy equals mass time c2... So, I wonder is there a boundary where what we think of as space is expanding into 'not space'?
@@michaelread539 the space they are in si not actually moving. the space between far away enough objects is expanding. it's conceptually easier to think of them as moving away but technically it's just there's more space between you & them so they never experience relativistic effects of moving close to the speed of light
I really enjoyed this episode, even though it challenged the limits of my intellect and understanding! Maybe even because of that...
Nice thumbnail!
Drink and a snack prepeared.
Traveling back near the big bang would not only be difficult due to high energy, but anything you do, even merely existing there, would affect the evolution of galaxies. All the smallest of changes would magnify as the universe evolves. You hull cutting through that plasma would change densities, and that would in turn create greater densities that probably wouldn't have occurred otherwise. Add Chaos theory on top of that and you changed everything in the end.
wonder if our universe is still creating new mass by expanding
That would certainly be in line with Hawking's thesis that the net energy of the cosmos is zero. According to him (regarding the "Big Bang"): ""In the case of a universe that is approximately uniform in space, one can show that this negative gravitational energy exactly cancels the positive energy represented by the matter. So the total energy of the universe is zero." As cosmic spacetime expands into the future, more fermionic/bosonic matter must pop into existence to maintain the balance, just as it did at t-0.
What do you mean energy is not conserved? I thought matter and energy cannot be created and destroyed. Only converted into each other.
If our universe is not a closed system, then locally we would observe that the conservation is broken. I think he was talking about the system being open vs closed
@@krumuvecis Oh, right. Well yes. I was thinking the same thing. All the billions of light years that are now observable might be pretty much nothing compared to outer systems that pump in or out matter and energy into this system that we call the universe. But I think overall if you think of ALL of the stuff that exists regardless if we can detect it or not then I am pretty sure that matter and energy are indestructible. The only things they can do is to change from one spot to another or one size to another or one direction to another or one type to another and so on.
Computer analogy is WRONG.
Expanding a imaginary world from 1k pixels/ 1k pixles to 10k pixles/ 10k pixels is actualy exampding into HHD space. When your reach the HDD limit the"universe" is no longer expanding.
Stimulating, as usual, and even when you're blithely hand waving things like turning black holes into ramjets, your important contribution is ATTITUDE, i.e. that of being a positive futurist rather than a negative hand-wringing doomsayer (better to hand wave than hand-wring).
Stimulated Personal Observations:
1. Anything with a beginning is not infinite (or eternal).
2. The matter from a Big Bang is expanding into nothingness, UNLESS there is something else out there, then the nothingness becomes 'space' (between two objects). Without anything else out there, you have no reference to reference how fast or far your expansion is going.
3. Infinity is actually nothingness (just as eternity is changelessness). If you attain either, you have attained nothingness (and/or changelessness). Congratulations.
4. Given an infinite amount of something, you cannot attain all of it ('everything').
5. Once you have something, you can never go back to complete nothingness. (get over it - we are past that point in time) (or, more correctly, that point in change).
6. Since 'something coming from nothing' is a paradox, it means we are on the wrong track of thinking. It is like the paradox of backwards time travel - backwards time travel is a wrong track of thinking, because:
6. If you want to travel back in time, just run your timepiece backwards. Time is a tool we created to track change, which is a component of the physical world, not time. So what you really want to do is go back in change, a component of the physical world, and not time, which is a mental tool. So when physicists talk about time, they usually mean 'change' (get your act together, physicists).
7. From the broadest philosophical perspective, what you want to ask about all of this is, "How does it affect Broader Survival?" (which affects your individual prospects of long-term survival). Read the Philosophy of Broader Survival (and Ultimate Morality), for the Space Age, no less for the comprehensive body of thought on this. Future enlightened entities (biological or otherwise) will be living by it.
8. There is only 3 dimensions of space in the physical world (they are all your model needs). All else is either pure math, other properties, or the human tendency toward foolishness.
Another great concept development video in science, from a brilliant content creator
If the universe appears appears to be expanding at a similar rate in all directions from our relative perspective, wouldn't that more likely imply that our particular neighborhood is contracting? Otherwise wouldn't that imply we are at the exact center of the universe? This seems an unlikely coincidence and may be egotistical, as humans tend to be. Perhaps the observations we make themselves cause our local area to contract? Or do most attribute this coincidence to some theory of intelligent design?
"Most folks". That's you're problem, Isaac, putting people in boxes. EDIT: Nope. I was wrong. You're treating gravitons as if they were real. THAT'S your problem Isaac. There is no proof or evidence for the existence of gravitons. Treating gravitons as real is a serious problem.
The closer we get to a black hole, the more time slows down.
Would time not stop, at the point where we cross the event horizon?
And, by that reasoning…. As we fall further down into the black hole, could time then be actually moving “backwards”?
And if so…. Wouldn’t any light which “follows” us into the black hole, actually appear as though it was moving away from us, creating the illusion of an expanding universe?
In this scenario, time is actually moving backwards…. But, we measure it as moving forward, because that’s the only thing that makes sense to us.
Insert FINAL SPACE references here
Ok so we know that the universe wasn't a single point when it was around 370 00 'old'. But why it didn't collapsed back into singularity or few massive black holes, when the the matter was so densitly packed?
Per expansion: we could be in a origin particle, but its inner space metric shrank catastrophically, thus causing an apparent expansion of volume. (Weirdly, this could justify a big rip ending. Huh...)
If we had ftl tech, we could easily go past the cosmological event horizon, but we would still be limited by the speed we could achieve.
No, you'd be limited by debris hitting your ship at those speeds such that accelerating to even a fraction of that speed would turn tiny bits of dust into kinetic bombs.
If it's nessecary to make a disclaimer about other purely hypothetical concepts, it's probably good to add one to inflation also...since it's in most ways just invented to explain a assumption that appears to be nessecary to make our current best model work. It may very well not be a thing....not that I myself would have any clue if it is or if it isn't tho. Lol
Isaac- If a galaxy is outside of our event horizon- photons from that galaxy can never reach us. But from the photons perspective no time elapses and it arrives to us instantly.....
This reminds me of multiple fictional universes.. One is Minecraft and The Nether, the other is Warframe and The Void, a third is Warhammer 40,000's extradimentional plane, though I'm not as read up on Warhammer 40,000 as I am on Warframe and Minecraft
I mean if you started with a big bang their would only be a finite amount of energy within the universe to begin with? Even if the positive finite-infinity universe were expanding into negative void space that same amount of energy would be present within the volume of the universe. Curious though does that mean the universe absorbs or displaces that void space? What even is that void space made of? Or is that anti-matter space? Wouldn't that make void space infinitely larger then universal infinity? If it's anti matter space, aren't we the anti matter of their space?
Actually I'm curious, they say sleep is like a mini death. Does that mean dreamspace is another layer of space? When we die to we go to dreamspace? Is dream space outside of the universes physics model or does it have its own "laws"? Is dream space anti matter space? Or void space? Or merely a construct of the mind?
Or is it more probable that their is no "universe" and that this is a plane, so to speak, where literal evil beings live below, and higher beings live above?
I mean it's not like I havent turned on my light so to speak, and seen people's real faces before. So I'm assuming this place is more like an observation area? Or a prison of sorts? Or is this like a "dream factory" where smarter beings then you use "conscious construction" to "build" your theories based on some form of measurement, That adds a degree of "realism".
I tend to see the edge of the universe as being all around us all the time. We do not reach it by going a great distance, but by going at a great velocity. Perhaps by going faster than light. And not in the worm-hole or warp sense. Those are "cheats." But rather by actually, physically, breaking the light barrier. One of the more interesting aspects of a physical object approaching light speed is that it is compressed in the direction of travel. It's almost analogous to coming up against a wall which travels at just ahead of the spacecraft and which the craft is slowly being crushed into. Is the "wall" just the accumulation of greater mass as the energy being pushed out the back of the spacecraft is increasingly being turned into mass (inertia) instead of forward motion? Or is there a real barrier there? Perhaps we could get past it by shedding mass faster than it is accumulated by forward propulsion energy being converted into it. Whatever the method, once a physical object (or even photons) breaks through that barrier, it is at the true "edge of the universe." Or perhaps beyond it.
Energy is not conserved. And I know how to make a perpetual motion machine. The key is antimatter.
The conservation of energy arises from Noether's Theorem as it applies to time. This theorem states that anywhere time is symmetrical, energy must be conserved. Symmetry basically means that any experiment run today will give the same answer as yesterday, everything else being equal. This seems reasonable and unbreakable until we remember we are in an expanding universe. Experiments run today do not give the same results as they did 5 billion years ago. Space has grown.
This most notably shows up in the red shift of light. Light emitted long ago has longer wavelengths because the universe is expanding. That means it has less power because longer wavelength light has less energy. Yes, the expansion of the universe causes energy to be lost to the universe. Normally this effect is so slight it can be ignored in our local spacetime. But it is there and matters over cosmic scales.
Now for antimatter. Antimatter is seen by physicists as being like normal matter going backward in time. Since it is going backward, it is slowly gaining energy. At least in theory. Fine it's a totally impractical perpetual motion machine, but in theory...
I feel there is a very important point that has been lost regarding what the cosmological research actually says and what is assumed.
The main point to recognize is that aside from the CMB all the evidence we have in cosmology is statistically extremely weak in cosmological studies as our observations involve sample sizes that for even the best cosmological studies thus far we have only dealt with tens to hundreds of thousands of data points whether galaxies or quasars. This matters as it can be shown via statistics that the criteria to reach 5 sigma requires a data set measured in the *millions* of data points. In order to make observations of any significance with our extreme under sampled data sets we need a model that can be used to statistically expand our dataset *assuming that the model chosen is true*.
The key point to make abundantly clear is that conclusions based on testing a model are only as effective as said model is and they tend to only get to 2 -3 sigma level significance so any claims that we have proven dark energy is a thing are inaccurate. All we have the ability to show is that if we average over the sky then on average the rate of acceleration or the amount of redshift assumed to correlated with distance is positive. In this sense virtually all cosmology is unprincipled broadly applying the cosmological principal assumption which belays the Friedmann-Lemaitre-Robertson-Walker (FLRW) model cosmology. As a result it appears that data all supports FLRW cosmology because the data has been "corrected" to fit the Lambda CDM model based on FLRW cosmology and the cosmological principal.
Naturally if you only ever look for trees you will only ever find trees even if you are in an open savannah. Fundamentally this is what we call confirmation bias the only way to avoid this is to avoid making any assumptions that predispose a particular model.
In order to accurately test cosmology we need to test our assumptions which has not generally been done much if at all. Thus far all work that takes this approach in the local universe avoiding the use of the cosmological has regularly found much larger scale of structures than Lambda CDM and the cosmological principal permits should be noted that the standard cosmological model seems to be a bit oversimplified as the evidence appears to strongly contest the standard *assumption* that the expansion of the universe is isotropic. Really the idea for dark energy has never been proven because scientists only tested an isotropic expansion when their decelerating model didn't work. A uniform acceleration of expansion would correspond to a pure cosmological monopole term accelerating expansion. In this model it is assumed that the observed CMB dipole is purely kinematic allowing the observer to perform a reference frame transformation to the assumed cosmic rest frame
Recent work studying a 1.3 million quasars has finally started to reach statistically without making the assumptions that limit this approach for one 6the CMB is only isotropic if the redshift and blue shifts are purely kinematic. However if the dipole was kinematic it should apply regardless of the distance aside for cosmological redshift does not appear to isotropic it was nearly so but evidence suggests the acceleration of the expansion has become more biased since the CMB epoch in particular the rate of expansion is decelerating in one direction specifically the direction towards the rest of Laniakea the great attractor and beyond out at least to a redshift of 3 at the minimum and the rate of expansion is accelerating in all other directions to varying degrees with largest acceleration in the rate of expansion in opposition to the acceleration.
iopscience.iop.org/article/10.3847/2041-8213/abdd40
I don't know what this all means aside from the suggestion that should it continue then we will likely be pulled into the gravitational grip of M87 and the rest of the local Virgo super cluster node. This is supported by GAIA's evidence that the local group members the Large Magellanic Cloud , The Triangulum galaxy, the Milky Way and Andromeda and their respective satellites have only encountered each other recently long after the supposed dark energy dominance should have pushed them apart from each other. To be even more blunt based on the galactic history reconstruction of the Milky Way under Lambda CDM cosmology the take over of dark energy should have occurred prior to the Milky Way's first encounter with the Sagittarius dwarf spheroidal galaxy a collision responsible for the large starburst episode which transformed the Milky way from a low metallicity gas rich star poor galaxy into the high metallicity star rich galaxy we see today. The sun formed at the tail end of this major starburst episode which resulted in the formation of over half the stars the Milky Way has ever produced so were Lambda CDM to be true it would suggest we should not exist. That is a big problem!
sci.esa.int/web/gaia/-/galactic-crash-may-have-triggered-solar-system-formation
I suspect that this observation of anisotropy has some connection to the proof for the no big crunch theorem which shows via a prof by contradiction that in order to be a valid solution to the Einstein field equations that for a flat or open universe there can not be a maximum spatial volume in any time slice that is to say the direction of the rate of expansion can not change i.e. an accelerating universe must continue to accelerate forever. It also suggests a direct connection to the second law of thermodynamics and the properties of space itself. One possibility to ensure this rule holds for the Einstein field equations that I hypothesize is perhaps there is a GR analog to Newton's third law which conserves the mean rate of expansion with an equal and opposite acceleration to accommodate any deceleration spread over the distance in opposition to the acceleration (thus ensuring that it will be weaker in absolute magnitude compared to the mutual gravitational attraction but still significant over cosmological distances.
iopscience.iop.org/article/10.1088/1475-7516/2016/10/022