One can be only humbled by watching Sean Carroll so far 44 lectures (60-70 hours all together). His smooth and elegant delivery of complex concepts, including historical details and credits to past contributors, his personal "stands" on controversies, clear delineation of facts versus mere hypotheses --- all delivered with high scientific integrity -- are truly unparalleled. I learned a lot from this lectures, Sean's books and "Mindscape" interviews -- including just how little I know about theoretical physics. An immense pleasure so far and even greater gratitude and many thanks for your efforts.
Fantastic explanations. I think this is my fave video yet, having followed them all. I now realise that I have not understood universal expansion properly until now. Looking forward to whatever is next!
The easy conversational tone of these videos is probably the most profoundly useful piece of educational presentation I've ever had the pleasure of participating in.
Wow, just wow. I love your work. You make everything so accessible. I am a prospective physics graduate student and I have been reading two of your books "Spacetime and Geometry" your GR textbook, and I've also been reading your popular book "Something deeply hidden". Love your content.
A real pleasure to watch. SC makes a difficult subject fascinating to learn about. Great sense of humour, beautifully presented with just the right balance of basic ‘stuff’ and depth. Such a positive contribution to on line education. Thank you.
Sean, one day, a new star will shine in the cat eye's nebula, and that new star will be Ariel, watching you Sean. PS : More seriously, thx you very much professor.
57.21 "I'm not showing you what that equation is, it's a mess." I am a muscian , I like to listen to you while practicing. I like comedy but I don't don't like comedians in general. I don't know beans about equations. I think that was one of the greatest set ups for a punch line EVER! Almost an hour! I think you are hilarious. I am hoping that someone collects and edits your"inflation rants". Absolutely the best bit on inflation since Victor Borge. I hope there is some way he gets to hear it. He would have a great come back I am sure. Thanks so much for taking the time to make these things
Time itself is likely a derivative property of the universe that is governed by, for lack of a better term, the vacuum pressure of space. The vacuum pressure of space is what governs the flow of energy from field element to field element. Time is continuous at a level which we cannot sense, measure or "know", but becomes discrete and therefore "knowable" at the Plank scale where we can sense the transfer of energy from one field element to another.
Thanks again Professor Sean, for providing something really worth watching on a Sunday evening. . . . Hope we’re not keeping you from church, ha, ha !! . . . BTW, if I could mention this again, what are your opinion(s) please, of Roger Penrose’s objections to Inflationary Cosmology ? Thanks. and best wishes from West Wales.
On the question about conservation of energy - the energy of the matter in the box is NOT constant...it's kinetic energy is decreasing with time as the expansion of the universe proceeds... Also, raisins and pennies are solid - galaxies are not.
I mean, inflation does _sort of_ explain why entropy was small, in that the low-entropy state was extremely simple to describe. It's not entirely clear we will ever get any meaningful grip on questions like "why is there something as opposed to nothing?" but descriptively simple beginnings have _something_ to recommend them.
As always great lecture, thank you. I'm wandering if that magnetic dipol nature could be compared in a distant way to what happens when you separate two quarks away and doing so you apply enough energy to actually create new pairs out of gluon bond?
My Hypothesis: Vibrations that produce EM waves also produce Gravity Waves (perturbations). Photons released (EM waves) also produce a local gravity field (energy is equivalent to mass). Photon's gravity and the Gravity Waves "attract", hence the photons stick to the GW and travel with it (photons are glued to the GW and travel with it). It isn't the speed of light that is a universal or fundamental constant, it is the speed of GW that carries light. Light doesn't have the stature that GW has…If during inflation GW traveled faster then light traveled faster, Lorentz factor accommodates to speed of GW.
You need a better example than the metal disk resting on the elastic membrane. The static friction provides a limiting value greater than zero for a tensioned membrane, although obviously very small, as you said. The vacuole is perhaps better, but this starts to appear like the entanglement phenomenon, not readily explicable in words. Thanks for these excellent discussions and elucidating presentations.
Prof Carroll, what are your thoughts on Prof Penrose's Conformal Cyclic Cosmology? I've been thinking about it a lot for the past few months and it seems like a beautiful solution to the smoothness of the CMB question without the need to introduce an inflaton field.
Sorry to comment the wrong video, but earlier you talked about momentum and used Silly Putty in an example of inelastic collision. There is hardly any household substance that is /less/ appropriate for the purpose. I think you meant regular modelling clay. (Silly putty collides elastically, but turns to liquid when not stressed.) Thank you for an excellent series!
So the CMB stems from the 2nd order kinetic energy density driving the accelerated expansion of a spherical universe. As the universe keeps expanding, this second order energy density per unit volume decreases. As the CMB drives toward zero, the accelerated expansion of the universe declines as well. Eventually the universe expands at a uniform rate.
One request, could you put the chapter number and such, before the series title, UA-cam truncates it, and that makes it hard to find what one is looking for. Thanks.
Dr. Carroll, The Michelson Morley conclusions are built on two underlying assumptions which need to be re-examined. 1) That light is a discrete entity, distinct from the luminiferous aether which resists its motion. 2) the luminiferous aether is a static, UNIFORM field that extends throughout the universe in all directions. If light is not a discrete entity, apart from the aether, rather it is an energetic wave form that passes through the aether AND if aether is actually more fluid and is capable of having regional rotation that surrounds, for example, the experimental apparatus...well, then the null result from the experiment still makes sense. If we can get some respect for the aether, we can explain the rapid expansion of the universe and the relative uniformity of the CMB. We can also explain why light is both a wave and a particle and why the mass of that particle appears to be zero...but that is a separate issue.
If there is an aether, the big bang would represent a point (literally a point) in time when all of the energy within the known universe was concentrated into a single point, probably a fundamental particle of aether, then it exploded/collided into the rest of the aether, initially pushing it all away until the aether (or call it the vacuum energy of space if that helps) collapsed back to the center area of the big bang. In the mean time, the energy of the big bang explosion imparted all of the energy of our known universe at relatively uniform radial distance from the center of the big bang explosion, while the rest of the aether was pushing back in to fill the actual vacuum left by the bang. The point at which the big bang reaction back to the center occurs is when time essentially (and therefore the universe) begins. The kinetic energy density of the universe at this point is so intense, there is no chance for relative, localized rotations of aether (i.e. matter) to form. As the universe expands, the density decreases, eventually allowing matter to form, but the "slug" of aether that contains our known universe is still being accelerated outward like the surface of a balloon being filled with air. The CMB is created where the slug of big bang aether meets the relatively undisturbed aether as its expands.
And if you wanna get real freaky, imagine when the rest of the aether collapses back to the origin point of the big bang. It would most likely collide again, bounce back and do the same thing all over again.....continuously reverberating, creating another "universe" within the same universal canvas right behind the previous universe, ad finitum until the center core of big bang energy runs out of juice. Not quite the "multiverse" that some are thinking of, but a form of multiverse in a sense.
If baryonic matter is itself comprised of animated or energetic dark matter, it wouldn't be capable of locally or "relatively" sensing the other dark matter that surrounds it. Its not until you view it at an aggregate level, far away from the observer (i.e. at the cosmological scale), that you can sense the composite effect of dark matter carrying energy that does not manifest itself as baryonic matter. .
It's the smallest duration where we can say meaningful things about the universe. Smaller durations absolutely exist. Likewise with the Planck length. It's the smallest distance at which we can say anything meaningful about distance, but the universe isn't cut up into Planck sized volumes. It may be there is an actual smallest time step or smallest length or you can always zoom in, but the Planck sizes are unrelated.
@@hhaavvvvii I stand corrected. Thank you for taking the time to explain. I suppose mathematically you can always go smaller; we just might not ever be able to measure.
Why would the early Universe have low entropy moving from a singularity, and a Blackhole be high entropy, moving forward in time, in the direction to the Blackholes singularity. Is it to do with the direction of time, even though time is considered to be emergent.
Certain cosmology asserts that black hole will start new universe.. Given that only a tiny fraction of matter in our universe is captured by any black hole, does this cosmology assumes that the succeeding universes will get smaller and smaller until there is not enough matter left for next black hole formation? I wonder what was in the mind of those cosmologists.
Not really related but it is what I thought about and this is probably a good place to ask: Is there any argument against the possibility that space is quantized (maybe with the planck length) and that time is quantized? Thanks for any answers.
When mass is converted to energy or vice versa the calculations fall apart when time is considered. Kg converts to (A^2s^2/m)x 10^-7, A^2 x 10^-7 converts to Kgm/s^2, m converts to (A^2s^2/kg) x 10^-7 while seconds diverges into three nonsensical solutions sq.rt.Kgm/A, sq.rt.Kg/Asq.rt.m and sq.rt.Kgm^3/As. So no time is not quantized but is continuous.
You said that one knows the total amount of mass in the universe. So if the universe is inifinite it must be rather dense as we get further and further away.
My explanation when I correct the statement "The universe came into existence" goes like this: For someone to come into the house, the house must first be present and devoid of that person. If a house is built around me, I acquire the property of being in it, but I never came into it. The universe similarly is in existence, but never came into it.
Conservation of Energy: It appears to me that the rescaling of the universe is a conservative effect. That is, if you were to go back to the previous scale (e.g. reign in a section of the universe and make it scaled smaller) then the value of E would be restored to what it was when it was previously that scale. This means you can describe the scale factor has having a type of potential energy, that balances things. If the universe is open and does not re-collapse, then this never happens, but that doesn't change the principle. Is there a reason why we don't simply call it a form of potential energy? In GR _all_ forms of energy, including potential (i.e. energy storage) affect the energy tensor. Here we're saying that a potential (source/sink to which E can be transferred) is _outside_ the total E that affects curvature. In order to be excused from Noether's Theorem, we have to say that it's a change *to* the laws of the universe, rather than a change to the conditions *within* the universe. It is contradictory to say it's a change to the laws of the universe while writing equations that explain it: it's a law to *something*, and if that something is not "the universe" then we're just arguing semantics. by writing dE/dt = f(matter,spacetime) you are agreeing that E is dependent on the configuration (integrate both sides). This is what we ordinarily call "potential energy". We must say that the stress-energy tensor of GR simply does not include this form of energy, or is balanced by another term (involving the scaling factor) on the other side.
58:50 "When I was your age" ... Sorry professor, you have never, ever been my age. When you get to be my age, I'll probably be dead. Anyway, thank you for your effort on educating us on the important things in the Universe.
To me, it would be a whole lot weirder if the initial state of the universe had all kinds of asymmetries and inhomogeneities. So why is everyone trying to tell me that there needs to be some sort of explanation for the homogeneity of the CMB? I don't get why it would be any other way. What would be the cause of the lumps you want to see? It makes no sense.
I don't really see the problem with the idea that the entropy of the early universe was much lower than at present. Isn't this just a natural consequence of the Second Law of thermodynamics?
It's funny that we ask why the energy should be the same at two points in the horizon problem. I would ask why two things should be different. There is more information in an asymmetric universe than a perfectly uniform one. It's a higher entropy. More information needs more explanation. This has always seemed backwards to me.
If GR doesn't explain the Big Bang, why do you believe it can explain the fate of the Universe? If QM needs to be integrated with gravity, GR needs to be integrated with QM... This is preposterous... 😜
It’s funny how the q&a is just a way to use half as many natural numbers. They give rise to many more questions than were ever posed!! 😂 What do you mean the curvature of an infinite universe was infinitely small? Ahahahah, no wonder Lovecraft came up with understanding the ultimate truth as a way to lunacy in the 1920s
One can be only humbled by watching Sean Carroll so far 44 lectures (60-70 hours all together).
His smooth and elegant delivery of complex concepts, including historical details and credits to past contributors, his personal "stands" on controversies, clear delineation of facts versus mere hypotheses --- all delivered with high scientific integrity -- are truly unparalleled.
I learned a lot from this lectures, Sean's books and "Mindscape" interviews -- including just how little I know about theoretical physics.
An immense pleasure so far and even greater gratitude and many thanks for your efforts.
,
Fantastic explanations. I think this is my fave video yet, having followed them all. I now realise that I have not understood universal expansion properly until now. Looking forward to whatever is next!
The easy conversational tone of these videos is probably the most profoundly useful piece of educational presentation I've ever had the pleasure of participating in.
Wow, just wow. I love your work. You make everything so accessible. I am a prospective physics graduate student and I have been reading two of your books "Spacetime and Geometry" your GR textbook, and I've also been reading your popular book "Something deeply hidden". Love your content.
A real pleasure to watch. SC makes a difficult subject fascinating to learn about. Great sense of humour, beautifully presented with just the right balance of basic ‘stuff’ and depth. Such a positive contribution to on line education. Thank you.
*High quality content here. Keep em coming Sean*
Hii!! Brother I used to watch your UA-cam videos the way you explain the stuff there they're quite interesting☺️☺️
This two-hour lecture by Professor Carroll is simply superb. Thank you!
find the best content here. Thanks Prof. Sean
It is good that I can time travel within this video. Thanks Sean!
Sean, one day, a new star will shine in the cat eye's nebula, and that new star will be Ariel, watching you Sean.
PS : More seriously, thx you very much professor.
Absolutely amazing! My mind is blown to pieces!
1:26:41 - This advice will prove highly appropriate, I claim. ^.^
57.21 "I'm not showing you what that equation is, it's a mess." I am a muscian , I like to listen to you while practicing. I like comedy but I don't don't like comedians in general. I don't know beans about equations. I think that was one of the greatest set ups for a punch line EVER! Almost an hour! I think you are hilarious. I am hoping that someone collects and edits your"inflation rants". Absolutely the best bit on inflation since Victor Borge. I hope there is some way he gets to hear it. He would have a great come back I am sure. Thanks so much for taking the time to make these things
Time itself is likely a derivative property of the universe that is governed by, for lack of a better term, the vacuum pressure of space. The vacuum pressure of space is what governs the flow of energy from field element to field element. Time is continuous at a level which we cannot sense, measure or "know", but becomes discrete and therefore "knowable" at the Plank scale where we can sense the transfer of energy from one field element to another.
Thanks again Professor Sean, for providing something really worth watching on a Sunday evening.
. . .
Hope we’re not keeping you from church, ha, ha !!
. . .
BTW, if I could mention this again, what are your opinion(s) please, of Roger Penrose’s objections to Inflationary Cosmology ? Thanks. and best wishes from West Wales.
You are genius sir
The Universe is so cool and even cooling more!
On the question about conservation of energy - the energy of the matter in the box is NOT constant...it's kinetic energy is decreasing with time as the expansion of the universe proceeds...
Also, raisins and pennies are solid - galaxies are not.
You’re a legend! Keep em coming.
As usual: the best!
I mean, inflation does _sort of_ explain why entropy was small, in that the low-entropy state was extremely simple to describe. It's not entirely clear we will ever get any meaningful grip on questions like "why is there something as opposed to nothing?" but descriptively simple beginnings have _something_ to recommend them.
As always great lecture, thank you. I'm wandering if that magnetic dipol nature could be compared in a distant way to what happens when you separate two quarks away and doing so you apply enough energy to actually create new pairs out of gluon bond?
Sean, Thanks for another video!
My Hypothesis: Vibrations that produce EM waves also produce Gravity Waves (perturbations). Photons released (EM waves) also produce a local gravity field (energy is equivalent to mass). Photon's gravity and the Gravity Waves "attract", hence the photons stick to the GW and travel with it (photons are glued to the GW and travel with it).
It isn't the speed of light that is a universal or fundamental constant, it is the speed of GW that carries light. Light doesn't have the stature that GW has…If during inflation GW traveled faster then light traveled faster, Lorentz factor accommodates to speed of GW.
You need a better example than the metal disk resting on the elastic membrane. The static friction provides a limiting value greater than zero for a tensioned membrane, although obviously very small, as you said. The vacuole is perhaps better, but this starts to appear like the entanglement phenomenon, not readily explicable in words. Thanks for these excellent discussions and elucidating presentations.
Hi! And thanks for you immense work. Can we explore the Hard Problem in science here? 👩🏽🚀🙈🙉
Prof Carroll, what are your thoughts on Prof Penrose's Conformal Cyclic Cosmology? I've been thinking about it a lot for the past few months and it seems like a beautiful solution to the smoothness of the CMB question without the need to introduce an inflaton field.
Thank you so much for this content
Sorry to comment the wrong video, but earlier you talked about momentum and used Silly Putty in an example of inelastic collision. There is hardly any household substance that is /less/ appropriate for the purpose. I think you meant regular modelling clay. (Silly putty collides elastically, but turns to liquid when not stressed.)
Thank you for an excellent series!
So the CMB stems from the 2nd order kinetic energy density driving the accelerated expansion of a spherical universe. As the universe keeps expanding, this second order energy density per unit volume decreases. As the CMB drives toward zero, the accelerated expansion of the universe declines as well. Eventually the universe expands at a uniform rate.
One request, could you put the chapter number and such, before the series title, UA-cam truncates it, and that makes it hard to find what one is looking for. Thanks.
My yellow submarine thesis went Nowhere! Very Good!
Dr. Carroll,
The Michelson Morley conclusions are built on two underlying assumptions which need to be re-examined. 1) That light is a discrete entity, distinct from the luminiferous aether which resists its motion. 2) the luminiferous aether is a static, UNIFORM field that extends throughout the universe in all directions.
If light is not a discrete entity, apart from the aether, rather it is an energetic wave form that passes through the aether AND if aether is actually more fluid and is capable of having regional rotation that surrounds, for example, the experimental apparatus...well, then the null result from the experiment still makes sense.
If we can get some respect for the aether, we can explain the rapid expansion of the universe and the relative uniformity of the CMB. We can also explain why light is both a wave and a particle and why the mass of that particle appears to be zero...but that is a separate issue.
If there is an aether, the big bang would represent a point (literally a point) in time when all of the energy within the known universe was concentrated into a single point, probably a fundamental particle of aether, then it exploded/collided into the rest of the aether, initially pushing it all away until the aether (or call it the vacuum energy of space if that helps) collapsed back to the center area of the big bang. In the mean time, the energy of the big bang explosion imparted all of the energy of our known universe at relatively uniform radial distance from the center of the big bang explosion, while the rest of the aether was pushing back in to fill the actual vacuum left by the bang.
The point at which the big bang reaction back to the center occurs is when time essentially (and therefore the universe) begins. The kinetic energy density of the universe at this point is so intense, there is no chance for relative, localized rotations of aether (i.e. matter) to form. As the universe expands, the density decreases, eventually allowing matter to form, but the "slug" of aether that contains our known universe is still being accelerated outward like the surface of a balloon being filled with air. The CMB is created where the slug of big bang aether meets the relatively undisturbed aether as its expands.
And if you wanna get real freaky, imagine when the rest of the aether collapses back to the origin point of the big bang. It would most likely collide again, bounce back and do the same thing all over again.....continuously reverberating, creating another "universe" within the same universal canvas right behind the previous universe, ad finitum until the center core of big bang energy runs out of juice. Not quite the "multiverse" that some are thinking of, but a form of multiverse in a sense.
“Stephen Hawking, God, or the Wave Function of the Universe” is maybe my favourite thing you have said.
If baryonic matter is itself comprised of animated or energetic dark matter, it wouldn't be capable of locally or "relatively" sensing the other dark matter that surrounds it. Its not until you view it at an aggregate level, far away from the observer (i.e. at the cosmological scale), that you can sense the composite effect of dark matter carrying energy that does not manifest itself as baryonic matter. .
16:50 "one quadrillionth of a plank time"? Um, I thought the plank time was the smallest there is.
It's the smallest duration where we can say meaningful things about the universe. Smaller durations absolutely exist. Likewise with the Planck length. It's the smallest distance at which we can say anything meaningful about distance, but the universe isn't cut up into Planck sized volumes. It may be there is an actual smallest time step or smallest length or you can always zoom in, but the Planck sizes are unrelated.
@@hhaavvvvii I stand corrected. Thank you for taking the time to explain. I suppose mathematically you can always go smaller; we just might not ever be able to measure.
Why would the early Universe have low entropy moving from a singularity, and a Blackhole be high entropy, moving forward in time, in the direction to the Blackholes singularity. Is it to do with the direction of time, even though time is considered to be emergent.
Certain cosmology asserts that black hole will start new universe.. Given that only a tiny fraction of matter in our universe is captured by any black hole, does this cosmology assumes that the succeeding universes will get smaller and smaller until there is not enough matter left for next black hole formation? I wonder what was in the mind of those cosmologists.
Cant find the list of videos with titles.. 48 videos and all with the same cover and intro, could not find specific one by the title..
Not really related but it is what I thought about and this is probably a good place to ask: Is there any argument against the possibility that space is quantized (maybe with the planck length) and that time is quantized? Thanks for any answers.
When mass is converted to energy or vice versa the calculations fall apart when time is considered. Kg converts to (A^2s^2/m)x 10^-7, A^2 x 10^-7 converts to Kgm/s^2, m converts to (A^2s^2/kg) x 10^-7 while seconds diverges into three nonsensical solutions sq.rt.Kgm/A, sq.rt.Kg/Asq.rt.m and sq.rt.Kgm^3/As. So no time is not quantized but is continuous.
The Moon is moving out therefore our gravity well is flattening to more shallow shape, thus Brooklyn is expanding.
Is there a model where expansion is a volume (the universe) filling a void (space)?
You said that one knows the total amount of mass in the universe. So if the universe is inifinite it must be rather dense as we get further and further away.
My explanation when I correct the statement "The universe came into existence" goes like this: For someone to come into the house, the house must first be present and devoid of that person. If a house is built around me, I acquire the property of being in it, but I never came into it. The universe similarly is in existence, but never came into it.
Conservation of Energy: It appears to me that the rescaling of the universe is a conservative effect. That is, if you were to go back to the previous scale (e.g. reign in a section of the universe and make it scaled smaller) then the value of E would be restored to what it was when it was previously that scale. This means you can describe the scale factor has having a type of potential energy, that balances things.
If the universe is open and does not re-collapse, then this never happens, but that doesn't change the principle.
Is there a reason why we don't simply call it a form of potential energy? In GR _all_ forms of energy, including potential (i.e. energy storage) affect the energy tensor. Here we're saying that a potential (source/sink to which E can be transferred) is _outside_ the total E that affects curvature.
In order to be excused from Noether's Theorem, we have to say that it's a change *to* the laws of the universe, rather than a change to the conditions *within* the universe. It is contradictory to say it's a change to the laws of the universe while writing equations that explain it: it's a law to *something*, and if that something is not "the universe" then we're just arguing semantics.
by writing dE/dt = f(matter,spacetime) you are agreeing that E is dependent on the configuration (integrate both sides). This is what we ordinarily call "potential energy".
We must say that the stress-energy tensor of GR simply does not include this form of energy, or is balanced by another term (involving the scaling factor) on the other side.
Sean, please invite Gisin to talk about INTUITIONISTIC MATH and physics on your podcat.
Thanx Mr Carroll 🙂👍
can you do a talk about chantal's paradox one day?
Anything beyond our viewable Universe doesn't exist until viewed or measured ?
So would the many world's still be branching if there were no humans? Would the branching happen in a static Universe?
I put up with you - what a pleasure
I feel blessed
Hypothetical question of Einstein, if Space = 0, and the Universe = 1, what, if any, would be the tensile strength of Space/Time?
58:50 "When I was your age" ... Sorry professor, you have never, ever been my age. When you get to be my age, I'll probably be dead. Anyway, thank you for your effort on educating us on the important things in the Universe.
Last time I've been this early Electroweak was still a force!
Is the universe electrically charged?
if the hubble's constant changes then why we call it as a constant
It is constant in space, not in time.
To me, it would be a whole lot weirder if the initial state of the universe had all kinds of asymmetries and inhomogeneities. So why is everyone trying to tell me that there needs to be some sort of explanation for the homogeneity of the CMB? I don't get why it would be any other way. What would be the cause of the lumps you want to see? It makes no sense.
I don't really see the problem with the idea that the entropy of the early universe was much lower than at present. Isn't this just a natural consequence of the Second Law of thermodynamics?
Ty Sean
Black Hole: expention regulator! I love it. 👩🏽🚀🙈🙉
I was confused over the Cephid variables.I listen out of interest and am not a science graduate.
It's funny that we ask why the energy should be the same at two points in the horizon problem. I would ask why two things should be different. There is more information in an asymmetric universe than a perfectly uniform one. It's a higher entropy. More information needs more explanation. This has always seemed backwards to me.
The Brooklyn Bridge might still be there, but the Hudson is likely to expand owing to global warming and rising sea levels !
@@michaelsommers2356 Thanks ! UK resident here. Not up on US river names.
Don't mess up with the equations Sean, or we'll be forced to beat the crap out of you lol!
Thanks
Shouldn't the most fundamental question in Physics be "Why is the speed of light limited?" I think it's the gateway to unlocking unification.
Don't worry, we're all friends by now...
"When i was in your age"..? 🤔😄😄
Yay! Haircut! :-)
Problems with a WordPress-driven site? Well I never!
Who spotted Friedmann Equation in the video? 🤭🤭
If GR doesn't explain the Big Bang, why do you believe it can explain the fate of the Universe? If QM needs to be integrated with gravity, GR needs to be integrated with QM... This is preposterous... 😜
Cool! I’m expanding but not bcz of the universe ;-) Thanks for awesome lectures. Love these.
👏🏽👏🏽👏🏽
My favorite on so far.
BTW: You haven't been 67 yet......
Well, not if you experience time sequentially...
I wonder how many homeschoolers will come here for hair and cuticle lessons xD
Seriously Sean? "When I was your age..." Kids these days, sheesh. : )
It’s funny how the q&a is just a way to use half as many natural numbers. They give rise to many more questions than were ever posed!! 😂
What do you mean the curvature of an infinite universe was infinitely small? Ahahahah, no wonder Lovecraft came up with understanding the ultimate truth as a way to lunacy in the 1920s
GeneRelativity
God or Stephen Hawking.. They are one! 😂😂
the north star........
... Stephen hawking or God... Lol