An interesting sun factoid I came across which seems to be true is the energy density of the sun is only 276 watts per cubic meter which is about the same as a compost heap. It puts the difficulty of fusion reactors in perspective--we have to do a lot better than the sun to have a practical sized reactor--more pressure and/or hotter.
Thank you for taking the time to answer my far out question Fran, I had asked Fraser Cain a few years ago the same question and it's interesting to here the thoughts of those much much smarter than myself.
Great episode Fran. You might not be a whatever but you sure are smart, Thanks for the name drop of my song (I played the cowbell on the original). BTW when we started BOC we were two engineering school drop-outs.
All the King’s soldiers and all the King’s men and all the King’s energy could not make a piece of matter go faster than the speed of light. Thanks Fran for your excellent answers to many interesting questions.
So if I am understanding this correctly, the "outatime" license plate in the movie wasn't just a funny reference to time travel. It was a reference to basically breaking the equation. Mind Blown
Re FTL travel, what about Alcubierre's 1994 paper proposing warping space, following physics we already accept as true? ETA: Seems like there's been a new paper, by an Erik Lentz (March 2021) that offers theoretically possible FTL: "Breaking the warp barrier: hyper-fast solitons in Einstein-Maxwell-plasma theory"
Thank you so much for making me feel validated about my civil defense geiger counter detector collection.. I got so excited when you said you were warming it up.
With the pressure of a star acting on H2 and O2 I would assume that you get a plasma which is a mix of the two atoms. Molecules do not exist at that heat level. There might be some fusion still as fusion creates engery until Iron is created.
''Photon is massless'' I don't agree since if we can push an interstellar sail with lasers (photons) then it means that those photons has a mass (almost nothing) but they do.
they have energy and momentum but they still don't have mass K.E. = ½mv² and p = mv are just the non-relativistic excellent approximations for normal matter in classical mechanics There are formulae for the energy and momentum of a photon depending on its frequency, and not involving mass. if something has momentum that can be transferred when it collides with an object, and that still works if the incoming object is massless. Einstein won his Nobel Prize on this very topic in 1921, even though he had it figured out in a paper over 15 years earlier, but if you still want to disagree a century later that's up to you :)
On the speed of light thing. What causes gravitational lensing? Light comes from stars right? And they are traveling very fast around their galaxy. Does the light go out slower in the forward motion of the star and faster in the as it moves away from where it has been? Does it bend as it is moving? Is there a relationship with photons and magnets. Do magnets emit photons? Are all photons visible to the human eye?
light does not bend, it fallows spacetime in a straight line. it's spacetime that gets bend by mass. So gravitational lensing happens when light moves through the distortion of spacetime caused by a 'heavy' object. sometimes a helpful analogy is a rubber sheet, draw parallel lines on it, then stretch it out and throw a heavy object in the center. the object will from a funnel and the straight lines appear curved. it's obviously not perfect but it kind of gives you an idea
The explanations are close enough if you don't want to delve ever deeper into the detail. Much of physics teaching follows this approach of simple ways to model the behaviour which can become progressively more involved. A few examples, it's perhaps more correct to say that you can increase an object's (kinetic) energy almost indefinitely and in doing so will increase its momentum (and its inertia) without its velocity relative to any observer ever reaching c. You don't have to conclude that it's going into the mass, and there are at least 3 definitions of mass depending what property you are really interested in (including: how much stuff makes up the object, or how hard it is to accelerate the object, or some combination). In any case energy and momentum tend to be more useful than velocity and mass when dealing with objects moving through space or in orbit. As for the neutrinos, it's not just how much energy they have, but that without charge and minuscule mass, they are spectacularly unlikely to have any encounter with ordinary matter when passing through it, even something apparently dense as a even a whole planet. Being so much "smaller" than an electron, for them the volume inside any atom or molecule is practically empty to all intents and purposes. So because it's so difficult for them to actually hit anything, let alone hit it hard enough to disturb it (rather than just glance off) they are negligible compared with more lumpy forms of radiation. In physics, negligible does not mean 0, merely that it is completely dwarfed by any other factor you could care to consider for taking measurements, detection, or determining causal relationships.
I never met face to face someone who met face to face with a neutrino. And even if I did... that encounter would be irrelevant both ways. Human life and thus, experience is just an approximation.
You actually seem to know enough about science to be a Highschool science teacher. I nearly was one but found out that the knowing science part was a small element of the job.
I think you're wrong about the star made of water. I think the gravity and pressure would turn the water into plasma and then rip the molecules apart into O and H and, voila! new star born! also, I know stars can keep making heavier atoms and they do not collapse until they create iron, coz fusing iron wouldn't create enough force to keep the star from collapsing and that causes the star to become a supernova or something else!
I love the mad scientist hair, seriously style or super crazy sticking up and out everywhere and then put on some 'crazy eyes' and then do a full video on a more serious/technical topic. Never mention the hair and play it straight. Something like that would be great.
One nitpicking clarification: When talking about the speed of light, it really is talking about speed of light in VACUUM. Light does slow down in various materials, such as glass, plastics, crystals and so on. In those situations it becomes possible, although very rare, that some particles from a nuclear decay can travel slightly faster than light does in that material. A famous example is the Cherenkov radiation you can see as weird bluish haze in a nuclear reactor water during service times when the reactor vessel is opened. So, something can travel faster than light in that environment, but both travel slower than the Vacuum Speed of light.
My understanding is that photons in a material travel at the speed of light, get absorbed by particles of the material and re-emitted. So really it is the absorption/emission occurances that slow down the observed speed but the photons do not slow down.
Hey fran when u wanna reference a lot of anything, ie molecules maybe try using the phrase "shed load"to imply a large quantity...lotsa regards from ur fans in Eire as always. Bil
How do two hydrogens create a helium (which has two neutrons as well)? You'd need four hydrogens, and weak-force interactions to change two protons to neutrons.
E=mc2 is valid only for small values of E and M, and so long as the velocity of the object is a small portion of c. Otherwise there is an expanded version that expands the equation to account for large mass, energy or travel at a good part of c.
Questions for next time : I'm guessing our moon had to of been spinning early on in order to have formed itself, if so, what could have caused it to slow down in just a few 100 millions years? and Mercury having such a low melting point for a metal, does it seem to you like it's somehow an element out of place on Earth? Thanks.
The speed of light is the ultimate speed limit within a particular reference frame (Special Relativity, 1905); however, there is no speed limit when different reference frames are compared (General Relativity, 1916). Thus, FTL is only possible if space-time can be curved into a sphere, which closes off the space-time *inside* the sphere from the space-time *outside* the sphere. This is the basis of "warp drives," in which the starship is motionless within its bubble of space-time, which itself is moving "through" un-warped space-time at velocities that can be *much* faster than light.
While nothing with mass can move faster than light, space itself is not bound by this limit. That is why we're talking about the 'observable' universe, in that many galaxies are already moving away from us at a speed faster than light.
Q1 asked about a possible water star OR PLANET. Fran discussed only stars. One should consider comets whose heads are mostly ice described as "dirty snowballs". They are already in orbit around a star. To achieve the International Astronomical status of a planet, a "snowball" also needs sufficient mass to assume hydrostatic equilibrium (a nearly round shape), and to have "cleared the neighborhood" gravitationally around its orbit. The orbital radius must be large enough for the water world to remain frozen. No such icewater world has been observed yet but we cannot dismiss the possibility of finding one somewhere among the estimated trillion of mostly unidentified icy bodies in the Oort cloud. We have seen Comet Hale-Bopp that may have a radius of 30 km (19 mi) but it is far from pure water and has an evaporating tail. Q2 The ultimate limit to the speed of light is set IN A VACUUM, as user Pellervo Kaskinen has said.
I thought about it a bit, and the problem with water as star fuel is that there’s too much oxygen it seems like. Most of the weight would be oxygen. Oxygen needs about 1 billion K to fuse with itself. Hydrogen needs a 1/10th of that. What temperature would oxygen need to fuse with hydrogen I’m not sure. It seems likely to me that the collapse would not stop: by the time the temperature would be high enough for oxygen-hydrogen fusion, the thing would be too dense, and the energy of the fusion would not arrest the collapse - especially that there would be a lot of momentum in those oxygen atoms.
Re: potassium isotopes. I vaguely remember an article about truck loads of bananas occasionally setting off radiation alarms at border crossings. Sorry I can't remember the specifics.I think it was about setting detection to a point that would insure catching even a small amount of some materials being smuggled. Then, a large enough amount of potassium can nudge up to that level.
Hi Fran, I enjoyed you talking about cancers and so on, what are your thoughts on free radicals and how they interact within us to create the aging process? Do you think we will ever be able to stop age deterioration?
The speed of light issue being the reason any sci-fi involving interstellar travel uses some invented tech to sneak around it. I'm not sure that isn't possible. You can't travel faster, but you might be able to take a different path that effectively cuts the distance.
Decent p-p chain explanation. Bringing up the CNO cycle for more massive stars is the standard next step. Showing the solar system enrichment chart would have been nice, if only to show the by-4 peaks that correspond to helium capture/alpha process elements.
As for the ~final~ penultimate point, I also am not sure, but I think you'd get a star. The heating from gravitational collapse seems like it'd be sufficient to separate the two elements, which would then suggest fusion is possible to keep up the interior pressure. I can probably try to code up a simulation this weekend. It seems sufficiently interested to try. I agree on the lack of oxygen from any natural process. Something maybe fractured and cooled a white dwarf? And then sent all of the heavy stuff toward a cloud of hydrogen? And it wasn't Ne3 kelvin when it got there? And there wasn't a lot of dust to precipitate onto? -Or- just the right amount of dust? Sorry, I don't make videos. I do have a few degrees in astrophysics, so hopefully that counts for something.
That said, I have never done a Geiger counter selfie before. a) I need to get one; b) that's brilliant; c) If I ever have to teach a 101, that's my day-one exhibit. -Disagree on neutrinos.- but only in the given context, not the question. Answering question now, paragraphing complaint downward: alpha radiation is helium atoms. They can't penetrate, basically, anything. Skin solves the problem. A tiny thin sheet of plastic bag is the standard filter for labs. Beta is electrons. Those can get a bit further, but it's still generally shallow. Gamma radiation is photons. They can get pretty far, and a gamma ray hitting the DNA in your cells could cause it to fragment/mutate, and you probably end up with cancer (very few people end up turning into the Incredible Hulk. It's a bad bet). Neutrinos can go super far through your body. Like (this is a guess, not a guarantee; I should solve the cross-section problem) a million yous, stacked up to have a neutrino interact with something. "but there are lots of neutrinos" which suggests I've underestimated the number of yous, but given how much care needs to be taken to build neutrino detectors, you're almost certainly 99.99999999999999999% safe from neutrino spawned cancer. Most nuclear reactions send out neutrinos, as they balance the spin between the source and decay particles (you can't just make an electron from nothing. It has a spin, so you need to put out an a neutrino (an antineutrino if I'm remembering my particle physics right) to balance out the input from the output).
I'm also not a doctor. Well, I'm also not "that kind of" doctor. I am 100% committed to keeping your blood inside your skin, but beyond that, I'm not going to be that helpful.
Haha no it's pronounced the same as Neil in my case, other Nialls are pronounced like the river Nile. Thanks for picking my question btw! I guess at some point maybe we'll figure out how to cheat the speed limit. It would be awesome to be able to physically explore other galaxies.
What would happen if there was a massive collection of water in space that was as large as the sun? Would it start to condense on itself? Would it have more or less gravity than a similar sized actual star?
The superionic ice state theorized within ice giants pushes O into nice cubic lattices and the hydrogen flows where they're kind of free but not sufficiently and would decompress without the immense pressure. Interesting question. The oscillations of particles in the EM spectrum as traveling waves are a function of space time itself, I think anways. I always find it interesting that nobody ever wonders that if you could then how you would ever slow down! See, lead based paint worked! I'm Oldtrinos.
Logging in my area is causing a lot of increased water runoff. It is supposedly ruining the habitat of local salamanders. There's a local group always asking for volunteers to go replant the forest, but we have so many other problems to deal with they make me angry and my answer is always no. Now my friends call me "Newt Tree No's".
So for those of you with Geiger counters, I assume pretty much all of you repeated Fran’s measurement of herself (either just now, or at some point in the past). I did, and I couldn’t tell any difference between background and myself. What did others get for this test?
Cancer is like a lottery where all the prizes are awful. You can buy lots of tickets and never "win", or buy one and get the grand prize, but on average, buying fewer tickets means less risk.
According to the french version of the "abundance of the chemical elements" Wikipedia page, H is 74% of all matter in the universe, and He is 24%. So all other elements account for only 2% of all visible matter. There's a nice graph showing the relative abundance of all elements up to uranium (the higher elements have never been observed in nature). Keep in mind that this graph is based on a log (base 10) scale, so a difference of 1 unit in the log scale represents a factor of 10. There's a 10^12 difference between the abundance of H and U. We can look at the graph and come to interesting facts: Li is quite rare, almost as rare as gadolinium in fact. Si is much more readily available. Based on these conclusions, Si based batteries might make more sense economically speaking than Li batteries. Si batteries are still in their infancy though. We're living in interesting times, regarding sci and tech. Edit: Dang! You enable my nerdy pulsions! I just found (and bought) a G/M counter exactly like yours... :-D
?? I'm under the impression that the conditions at any Star are to severe for the atoms and molecules we know. My understanding is if you shoot some ice or water into the sun, the water molecules would quickly break down and the atoms, which are hydrogen and oxygen would also breakdown, then the next step would be plasma ( individual electrons, neutrons, and protons in electrical/magnetic fields ) but they may not last either and all the matter you shot in (water/ice) will likely be in subatomic particles and energy states. If and when it is ejected it can be reformed into matter somewhere later, and thus an endless cycle
I have a question for you Fran. If it ever becomes possible to travel the say 8 to ten light-years away but at say half the speed of light ie 16 to 20 years do you perceive any electronics issues with components or batteries.. if say that we could use "suspended" animation of longer periods, say 40 years would components and batteries be an issue?
Neutrinos rarely interact with normal matter. So even though there are billions of them streaming through your body every second it's unlikely that any of them will cause a mutation. You're far more likely to get a mutation from eating a single banana than from all the neutrinos which will pass through your body during your lifetime.
Another thought on the water star: She's right on the collapse into a blackhole bit, but as for the star life, she's a bit off. If sufficiently large, the star will burn through all elements up to Iron. All those reactions will produce extra energy that will add to the balance of gravity in to energy pressure out. However, once it creates iron, it ABSORBS energy in that reaction, breaking the balance, and the the star quicky collapses under gravity's influence in a few seconds, causing the extreme temperatures that cause a resulting supernova explosion, scattering the heavy bits of matter around. The really heavy elements beyond are formed during this time with all those nutrinos getting captured as it exlodes, (r and s processes). So ALL of that precious gold you love, is all born in the heart of a dying star...
If the original singularity that became the Big Bang was so dense and had such a tremendous gravitational attraction to it, how did it possibly fly apart?
None of us were there. It’s a likely scenario but nobody was there when the universe, or our solar system began. Why do we have so many supernova fragments in our planets? How is the sun not full of space junk? With all the solid objects that have hit Jupiter, why do we call it a ball of gas? There must be a solid sphere in there somewhere.
15:45 Thats called the Warp Barrier. As for the question for faster than light travel: I disagree on terminology. This is basically how its going to get marketed. Since you age slower at high speed it going to be important to look at how much you age on a trip. So you might define your travel-speed as distance/"personal time". If you only age 10years for your 50lightyear trip... thats Faster-Than-Light(TM) travel.
Friend what is the name of the shock wave that is caused by helium infusion when it creates helium. Is there a way to observe that shockwave. N I'm assuming it would be observable like a wave or as a magnetic disturbance. Or electromagnetic radiation. Maybe that release of energy also triggers other cascades
On the speed of light: There were bumper stickers going around during the time that 55 mph was being enforced most everywhere. It said, "186,000 miles per second. It's not just a good idea. It's the law".
I like all of your vids Fran - I love these vids - thanks tons for doing them, find myself hangin' on every word and description - deep stuff explained in a way that (at least I think) I'm understanding.
So traveling faster than the speed of light is not possible (with current understanding of physics) but traveling at the speed of light is possible by converting matter to photons and then reconverting photons at the other end back to mass.
"Ass Load Of Photons" would be a great album name!
Yes it would!
I came here to say this lol
@@beautifulsmall, also, " InterstellarOverdrive".
"Ass Load of Photons in the Heart of Our Son".
The nickname I'll now use for my 3Mw laser pointer/light saber (and no not .3 but 3 lol)
I know nothing about engineering or electronics (but. I do play guitar) but I find this channel and Franlab to be super duper interesting.
I would like to thank you for picking some interesting questions to answer. Thanks for another great video.
Fran Blanche - a Fountain of Knowledge.
I love the way you explain things. Thank you for being you.
An interesting sun factoid I came across which seems to be true is the energy density of the sun is only 276 watts per cubic meter which is about the same as a compost heap. It puts the difficulty of fusion reactors in perspective--we have to do a lot better than the sun to have a practical sized reactor--more pressure and/or hotter.
Laws are made to be broken. . . . . . take that light speed.
Thank you for taking the time to answer my far out question Fran, I had asked Fraser Cain a few years ago the same question and it's interesting to here the thoughts of those much much smarter than myself.
Great episode Fran. You might not be a whatever but you sure are smart, Thanks for the name drop of my song (I played the cowbell on the original). BTW when we started BOC we were two engineering school drop-outs.
All the King’s soldiers and all the King’s men and all the King’s energy could not make a piece of matter go faster than the speed of light. Thanks Fran for your excellent answers to many interesting questions.
Another great video. I love your channel and I love the GBV shirt!
Love the Q1 simple question and the all out amazing enthustiatic carl sagan style explanation. The knowledge and enthusiasm are similar.
That was interesting, Thank you, Fran.
So if I am understanding this correctly, the "outatime" license plate in the movie wasn't just a funny reference to time travel. It was a reference to basically breaking the equation. Mind Blown
Re FTL travel, what about Alcubierre's 1994 paper proposing warping space, following physics we already accept as true?
ETA: Seems like there's been a new paper, by an Erik Lentz (March 2021) that offers theoretically possible FTL:
"Breaking the warp barrier: hyper-fast solitons in Einstein-Maxwell-plasma theory"
Thank you so much for making me feel validated about my civil defense geiger counter detector collection.. I got so excited when you said you were warming it up.
With the pressure of a star acting on H2 and O2 I would assume that you get a plasma which is a mix of the two atoms. Molecules do not exist at that heat level. There might be some fusion still as fusion creates engery until Iron is created.
i like when 30 min's goes from being too much to not enough, thanks.
Fran Im a Fan (sorry for the pun) your explanation of the Sun beats all that I've learnt before. Keep safe and well.
My favorite Mad Scientist!...👏🏻👏🏻👏🏻
''Photon is massless'' I don't agree since if we can push an interstellar sail with lasers (photons) then it means that those photons has a mass (almost nothing) but they do.
they have energy and momentum but they still don't have mass
K.E. = ½mv² and p = mv are just the non-relativistic excellent approximations for normal matter in classical mechanics
There are formulae for the energy and momentum of a photon depending on its frequency, and not involving mass.
if something has momentum that can be transferred when it collides with an object, and that still works if the incoming object is massless.
Einstein won his Nobel Prize on this very topic in 1921, even though he had it figured out in a paper over 15 years earlier, but if you still want to disagree a century later that's up to you :)
Fran you are really good at explaining complex sets of scientific facts in such a way that they are easily understandable!
Cheers fran,that was really helpful.
15:50 - Fran having a tantrum in german. :D
Jokes aside, loved the video, your explanation was easy enough to make me understand it.
Great stuff, Fran.
Thanks, brilliant.
Love ya Fran! Have a great weekend!
question format is a winner
It seems like everything needed for traversing the universe including it being a vessel is about quarter of a Million Miles Away 🌑
On the speed of light thing. What causes gravitational lensing? Light comes from stars right? And they are traveling very fast around their galaxy. Does the light go out slower in the forward motion of the star and faster in the as it moves away from where it has been? Does it bend as it is moving? Is there a relationship with photons and magnets. Do magnets emit photons? Are all photons visible to the human eye?
light does not bend, it fallows spacetime in a straight line. it's spacetime that gets bend by mass. So gravitational lensing happens when light moves through the distortion of spacetime caused by a 'heavy' object.
sometimes a helpful analogy is a rubber sheet, draw parallel lines on it, then stretch it out and throw a heavy object in the center. the object will from a funnel and the straight lines appear curved. it's obviously not perfect but it kind of gives you an idea
13:52 School lesson learned well but the future is open to new insights. Remember even Einstein initially didn't under-scribe the quantum theory.
The explanations are close enough if you don't want to delve ever deeper into the detail. Much of physics teaching follows this approach of simple ways to model the behaviour which can become progressively more involved.
A few examples, it's perhaps more correct to say that you can increase an object's (kinetic) energy almost indefinitely and in doing so will increase its momentum (and its inertia) without its velocity relative to any observer ever reaching c.
You don't have to conclude that it's going into the mass, and there are at least 3 definitions of mass depending what property you are really interested in (including: how much stuff makes up the object, or how hard it is to accelerate the object, or some combination).
In any case energy and momentum tend to be more useful than velocity and mass when dealing with objects moving through space or in orbit.
As for the neutrinos, it's not just how much energy they have, but that without charge and minuscule mass, they are spectacularly unlikely to have any encounter with ordinary matter when passing through it, even something apparently dense as a even a whole planet.
Being so much "smaller" than an electron, for them the volume inside any atom or molecule is practically empty to all intents and purposes.
So because it's so difficult for them to actually hit anything, let alone hit it hard enough to disturb it (rather than just glance off) they are negligible compared with more lumpy forms of radiation.
In physics, negligible does not mean 0, merely that it is completely dwarfed by any other factor you could care to consider for taking measurements, detection, or determining causal relationships.
I never met face to face someone who met face to face with a neutrino. And even if I did... that encounter would be irrelevant both ways.
Human life and thus, experience is just an approximation.
TH-cam Channel, Astrum, on the effects of speed of light a year ago is Excellent. 💯🇺🇸❤️❤️❤️👍🐈
You actually seem to know enough about science to be a Highschool science teacher. I nearly was one but found out that the knowing science part was a small element of the job.
I think you're wrong about the star made of water. I think the gravity and pressure would turn the water into plasma and then rip the molecules apart into O and H and, voila! new star born! also, I know stars can keep making heavier atoms and they do not collapse until they create iron, coz fusing iron wouldn't create enough force to keep the star from collapsing and that causes the star to become a supernova or something else!
I love the mad scientist hair, seriously style or super crazy sticking up and out everywhere and then put on some 'crazy eyes' and then do a full video on a more serious/technical topic. Never mention the hair and play it straight. Something like that would be great.
One nitpicking clarification: When talking about the speed of light, it really is talking about speed of light in VACUUM. Light does slow down in various materials, such as glass, plastics, crystals and so on. In those situations it becomes possible, although very rare, that some particles from a nuclear decay can travel slightly faster than light does in that material. A famous example is the Cherenkov radiation you can see as weird bluish haze in a nuclear reactor water during service times when the reactor vessel is opened. So, something can travel faster than light in that environment, but both travel slower than the Vacuum Speed of light.
My understanding is that photons in a material travel at the speed of light, get absorbed by particles of the material and re-emitted. So really it is the absorption/emission occurances that slow down the observed speed but the photons do not slow down.
Hey fran when u wanna reference a lot of anything, ie molecules maybe try using the phrase "shed load"to imply a large quantity...lotsa regards from ur fans in Eire as always. Bil
By the bye go girl with the ol' windswept & interesting look..🤗
How do two hydrogens create a helium (which has two neutrons as well)? You'd need four hydrogens, and weak-force interactions to change two protons to neutrons.
Atoms fusing in the Sun is a multi-step process, the extra neutrons are cannibalized from additional hydrogens.
E=mc2 is valid only for small values of E and M, and so long as the velocity of the object is a small portion of c. Otherwise there is an expanded version that expands the equation to account for large mass, energy or travel at a good part of c.
The speed of love,nothing changs faster "Neil peart"
Questions for next time : I'm guessing our moon had to of been spinning early on in order to have formed itself, if so, what could have caused it to slow down in just a few 100 millions years? and Mercury having such a low melting point for a metal, does it seem to you like it's somehow an element out of place on Earth? Thanks.
The speed of light is the ultimate speed limit within a particular reference frame (Special Relativity, 1905); however, there is no speed limit when different reference frames are compared (General Relativity, 1916). Thus, FTL is only possible if space-time can be curved into a sphere, which closes off the space-time *inside* the sphere from the space-time *outside* the sphere. This is the basis of "warp drives," in which the starship is motionless within its bubble of space-time, which itself is moving "through" un-warped space-time at velocities that can be *much* faster than light.
"The whole shabang" - one of my fav expression. 😀
@@manifold1476 troll.
I enjoyed that. Thanks Fran!
While nothing with mass can move faster than light, space itself is not bound by this limit. That is why we're talking about the 'observable' universe, in that many galaxies are already moving away from us at a speed faster than light.
I wish more people have your intellect
And knowledge maybe? To live is to ask, to wonder and from nd some answers ...
And here I was waiting for the reference to the Mohs Scale the whole time.....
Well that cleared that up
Q1 asked about a possible water star OR PLANET. Fran discussed only stars. One should consider comets whose heads are mostly ice described as "dirty snowballs". They are already in orbit around a star. To achieve the International Astronomical status of a planet, a "snowball" also needs sufficient mass to assume hydrostatic equilibrium (a nearly round shape), and to have
"cleared the neighborhood" gravitationally around its orbit. The orbital radius must be large enough for the water world to remain frozen. No such icewater world has been observed yet but we cannot dismiss the possibility of finding one somewhere among the estimated trillion of mostly unidentified icy bodies in the Oort cloud. We have seen Comet Hale-Bopp that may have a radius of 30 km (19 mi) but it is far from pure water and has an evaporating tail.
Q2 The ultimate limit to the speed of light is set IN A VACUUM, as user Pellervo Kaskinen has said.
From death comes rebirth. The universe is so awesome...
I thought about it a bit, and the problem with water as star fuel is that there’s too much oxygen it seems like. Most of the weight would be oxygen. Oxygen needs about 1 billion K to fuse with itself. Hydrogen needs a 1/10th of that. What temperature would oxygen need to fuse with hydrogen I’m not sure. It seems likely to me that the collapse would not stop: by the time the temperature would be high enough for oxygen-hydrogen fusion, the thing would be too dense, and the energy of the fusion would not arrest the collapse - especially that there would be a lot of momentum in those oxygen atoms.
Re: potassium isotopes. I vaguely remember an article about truck loads of bananas occasionally setting off radiation alarms at border crossings. Sorry I can't remember the specifics.I think it was about setting detection to a point that would insure catching even a small amount of some materials being smuggled. Then, a large enough amount of potassium can nudge up to that level.
Hi Fran, I enjoyed you talking about cancers and so on, what are your thoughts on free radicals and how they interact within us to create the aging process? Do you think we will ever be able to stop age deterioration?
The speed of light issue being the reason any sci-fi involving interstellar travel uses some invented tech to sneak around it. I'm not sure that isn't possible. You can't travel faster, but you might be able to take a different path that effectively cuts the distance.
Decent p-p chain explanation. Bringing up the CNO cycle for more massive stars is the standard next step. Showing the solar system enrichment chart would have been nice, if only to show the by-4 peaks that correspond to helium capture/alpha process elements.
As for the ~final~ penultimate point, I also am not sure, but I think you'd get a star. The heating from gravitational collapse seems like it'd be sufficient to separate the two elements, which would then suggest fusion is possible to keep up the interior pressure. I can probably try to code up a simulation this weekend. It seems sufficiently interested to try.
I agree on the lack of oxygen from any natural process. Something maybe fractured and cooled a white dwarf? And then sent all of the heavy stuff toward a cloud of hydrogen? And it wasn't Ne3 kelvin when it got there? And there wasn't a lot of dust to precipitate onto? -Or- just the right amount of dust?
Sorry, I don't make videos. I do have a few degrees in astrophysics, so hopefully that counts for something.
That said, I have never done a Geiger counter selfie before. a) I need to get one; b) that's brilliant; c) If I ever have to teach a 101, that's my day-one exhibit.
-Disagree on neutrinos.- but only in the given context, not the question. Answering question now, paragraphing complaint downward: alpha radiation is helium atoms. They can't penetrate, basically, anything. Skin solves the problem. A tiny thin sheet of plastic bag is the standard filter for labs. Beta is electrons. Those can get a bit further, but it's still generally shallow. Gamma radiation is photons. They can get pretty far, and a gamma ray hitting the DNA in your cells could cause it to fragment/mutate, and you probably end up with cancer (very few people end up turning into the Incredible Hulk. It's a bad bet). Neutrinos can go super far through your body. Like (this is a guess, not a guarantee; I should solve the cross-section problem) a million yous, stacked up to have a neutrino interact with something. "but there are lots of neutrinos" which suggests I've underestimated the number of yous, but given how much care needs to be taken to build neutrino detectors, you're almost certainly 99.99999999999999999% safe from neutrino spawned cancer.
Most nuclear reactions send out neutrinos, as they balance the spin between the source and decay particles (you can't just make an electron from nothing. It has a spin, so you need to put out an a neutrino (an antineutrino if I'm remembering my particle physics right) to balance out the input from the output).
I'm also not a doctor.
Well, I'm also not "that kind of" doctor.
I am 100% committed to keeping your blood inside your skin, but beyond that, I'm not going to be that helpful.
You are a great teacher! Thanks Fran
Haha no it's pronounced the same as Neil in my case, other Nialls are pronounced like the river Nile. Thanks for picking my question btw! I guess at some point maybe we'll figure out how to cheat the speed limit. It would be awesome to be able to physically explore other galaxies.
What would happen if there was a massive collection of water in space that was as large as the sun? Would it start to condense on itself? Would it have more or less gravity than a similar sized actual star?
The superionic ice state theorized within ice giants pushes O into nice cubic lattices and the hydrogen flows where they're kind of free but not sufficiently and would decompress without the immense pressure. Interesting question.
The oscillations of particles in the EM spectrum as traveling waves are a function of space time itself, I think anways. I always find it interesting that nobody ever wonders that if you could then how you would ever slow down!
See, lead based paint worked! I'm Oldtrinos.
Logging in my area is causing a lot of increased water runoff. It is supposedly ruining the habitat of local salamanders. There's a local group always asking for volunteers to go replant the forest, but we have so many other problems to deal with they make me angry and my answer is always no. Now my friends call me "Newt Tree No's".
Buh-dum-tish
Space can expand faster than light.
You're a real geek if you even * have * a Geiger counter 😀 (And yes, I want one)
@@sideburn Then you must be either in your seventies or twenties, right?
So for those of you with Geiger counters, I assume pretty much all of you repeated Fran’s measurement of herself (either just now, or at some point in the past). I did, and I couldn’t tell any difference between background and myself. What did others get for this test?
@@sideburn Big Clive recommends a flir capable mobile phone on one of his videos.
"Nerd" not "Geek"! Geeks are circus freaks that bite off the heads of chickens. :-)
Great Episode Fran!!! You Rule!!!!
Space time can be bent or warped though....getting from point A to Point B.......faster than light not needed.
Cancer is like a lottery where all the prizes are awful. You can buy lots of tickets and never "win", or buy one and get the grand prize, but on average, buying fewer tickets means less risk.
When digital watches were the thing, I waited for one that includes a Geiger counter. Still waiting!
It's a Red Dwarf, Rimmer...
“Fun, fun, fun, in the sun, sun, sun…”
Yes! You are a Scientist. I like your channel so much.
Wants to play “I am a scientist…” by Guided By Voices when you say scientist. Lol love ur channel Fran.
According to the french version of the "abundance of the chemical elements" Wikipedia page, H is 74% of all matter in the universe, and He is 24%. So all other elements account for only 2% of all visible matter. There's a nice graph showing the relative abundance of all elements up to uranium (the higher elements have never been observed in nature). Keep in mind that this graph is based on a log (base 10) scale, so a difference of 1 unit in the log scale represents a factor of 10. There's a 10^12 difference between the abundance of H and U.
We can look at the graph and come to interesting facts: Li is quite rare, almost as rare as gadolinium in fact. Si is much more readily available. Based on these conclusions, Si based batteries might make more sense economically speaking than Li batteries. Si batteries are still in their infancy though.
We're living in interesting times, regarding sci and tech.
Edit: Dang! You enable my nerdy pulsions! I just found (and bought) a G/M counter exactly like yours... :-D
I wish you would sing the Fran lab song every time xoxo
Sorry Fran, but red dwarf stars (type M) are the most common stars in the Milky Way galaxy.
c is the speed of light IN VACUUM. you can make cloud of neutrinos that can overtake light pulse in glass or water
Interdimensional travel!...interesting subject.
We could call it... Sliding
?? I'm under the impression that the conditions at any Star are to severe for the atoms and molecules we know. My understanding is if you shoot some ice or water into the sun, the water molecules would quickly break down and the atoms, which are hydrogen and oxygen would also breakdown, then the next step would be plasma ( individual electrons, neutrons, and protons in electrical/magnetic fields ) but they may not last either and all the matter you shot in (water/ice) will likely be in subatomic particles and energy states. If and when it is ejected it can be reformed into matter somewhere later, and thus an endless cycle
I have a question for you Fran. If it ever becomes possible to travel the say 8 to ten light-years away but at say half the speed of light ie 16 to 20 years do you perceive any electronics issues with components or batteries.. if say that we could use "suspended" animation of longer periods, say 40 years would components and batteries be an issue?
Are you saying we are star dust? Are we golden? Are we then billion year old carbon? Who'd thunk it?
Joni Mitchell is correct! We really ARE stardust.
😨
Gee something to look forward to!
Que the twilight zone theme-YOU HAVE NOW ENTERED THE FRAN ZONE!!!
FRAN-I WANT TO GET THE HELL OUTTA SPACE!!!
Ahhh... the old paper taped to a block of foam trick. So that's how the universe works.
Fran knows ALL the display technologies.
Neutrinos rarely interact with normal matter. So even though there are billions of them streaming through your body every second it's unlikely that any of them will cause a mutation. You're far more likely to get a mutation from eating a single banana than from all the neutrinos which will pass through your body during your lifetime.
What about other than light? With properly controlled worm holes?
Q: Since matter is space/time condensed by information, is the 'hole' thus formed a gravity-well?
My memories from High School physics are rusty.
Another thought on the water star: She's right on the collapse into a blackhole bit, but as for the star life, she's a bit off. If sufficiently large, the star will burn through all elements up to Iron. All those reactions will produce extra energy that will add to the balance of gravity in to energy pressure out. However, once it creates iron, it ABSORBS energy in that reaction, breaking the balance, and the the star quicky collapses under gravity's influence in a few seconds, causing the extreme temperatures that cause a resulting supernova explosion, scattering the heavy bits of matter around. The really heavy elements beyond are formed during this time with all those nutrinos getting captured as it exlodes, (r and s processes). So ALL of that precious gold you love, is all born in the heart of a dying star...
Yah water star will put itself out pretty quick... but it not until it turns to wine. or platinum or etc.
Very good video!
If the original singularity that became the Big Bang was so dense and had such a tremendous gravitational attraction to it, how did it possibly fly apart?
None of us were there. It’s a likely scenario but nobody was there when the universe, or our solar system began. Why do we have so many supernova fragments in our planets? How is the sun not full of space junk? With all the solid objects that have hit Jupiter, why do we call it a ball of gas? There must be a solid sphere in there somewhere.
15:45 Thats called the Warp Barrier.
As for the question for faster than light travel: I disagree on terminology. This is basically how its going to get marketed. Since you age slower at high speed it going to be important to look at how much you age on a trip. So you might define your travel-speed as distance/"personal time". If you only age 10years for your 50lightyear trip... thats Faster-Than-Light(TM) travel.
Yeah this was really what I had intended the question to be understood as.
Friend what is the name of the shock wave that is caused by helium infusion when it creates helium. Is there a way to observe that shockwave. N I'm assuming it would be observable like a wave or as a magnetic disturbance. Or electromagnetic radiation. Maybe that release of energy also triggers other cascades
On the speed of light: There were bumper stickers going around during the time that 55 mph was being enforced most everywhere. It said, "186,000 miles per second. It's not just a good idea. It's the law".
I like all of your vids Fran - I love these vids - thanks tons for doing them, find myself hangin' on every word and description - deep stuff explained in a way that (at least I think) I'm understanding.
Guided by Voices reference?
Was anyone else waiting for Fran to pull out a guitar and perform a cover of a TMBG song?
So traveling faster than the speed of light is not possible (with current understanding of physics) but traveling at the speed of light is possible by converting matter to photons and then reconverting photons at the other end back to mass.
Light as spirit is faster than measurable.
Did you really hand paint the roller decks that you flip through in your opening?
Why would the lightest element accrete in the center, then rocky planets, asteroids, then gas giants, proceeding outward?
Couldn't h2O do the same...pressure creates plasma at the core?? If there is enough gravity/mass?