Really, we can't thank you enough, Arvin. Your work makes complex--vitally important--ideas available for all. There is no better definition of a great teacher.
The explanation at 7:05 regarding how the sizing of the early universe is possible is just fantastic - I haven't heard it explained that way - thank you
There isn't any expansion, it is only depletion of the energy of the light beams from very old spots of images of the galactic sources by the Laws: of Wien and Planck 's λ=σ/Τ, λ= ch/E. When the T and the E goes to 0 the λ goes to infinity. It is simple physics! The galaxies sources aren't still in a spot to supply with energy their old images. They are traveling over trajectories and if they exist nobody now could see their real images.
@@user-dialectic-scietist1 Wrong, there is expansion and has being proven. The Wien law does not account for the red shift of the spectrum of distant galaxies.
@@shadowmax889 And what about the Planck's Law? And why, please the law of Wien do not account? You mean that in one Galaxy, the temperatures of its stars are the same? The Wien's law is a universal law and with this law an Astronomer can tell you the temperature of a star be the color in the spectrum. That means, far away red, to cold. Because you do not like the answer, you can't through the law away. And the Wien law is going well with the law of Planck. I am translating my books in English now, and I have written there 15 points why the expansion is nonsense. Especially about space and time if they are the energy of the vacuum, they can't expand at velocities greater than c. The dogma of Einstein says, no material, no energy with speed greater than c. Furthermore, my friend, space and time couldn't create a traveling fabric, because from SR, they are opposite values. When space dilates, the time has to shrink, and Vice Versa. The expansion is impossible under any known physical law. Accept someone write new physics, but then everything we know about physics has to be thrown away. So, find an answer about Planck's law, and you said that it is proved the expansion. Please tell me where I can read about a proof, because it is light and only human eye.
@@user-dialectic-scietist1 What about Plank's law? The same because it does not explain the red shift in SPECTRUM. Wein and Plank's law are about the black body radiation and measure the temperature of stars, the thing is those laws do not explain the red shift in the spectrum of elements that make the distant galaxies. The spectrum of any element do not depend on the temperature, but the orbitals of its electrons. So if you have a galaxy with the spectrum of the hydrogen red shifted is not because it is colder, but because is moving away from you, the same thing goes if the spectrum is blue shifted, the galaxy is moving towards you. The expansion of the universe has being proved beyond doubt and do not violate Relativity (it was the derivation of the relativity equation that hinted to an expanded universe in the first place). Objects cannot move faster than C trough space, but space itself CAN expand beyond C, that's why the expansion of the universe do not violate relativity no need to any new law. The only question scientist are looking for an answer is not that space is expanding but is expanding at accelerated rates, and that is a mystery right now
Love seeing the most fascinating discoveries in science made by my colleagues distilled into such delicious knowledge nuggets! What’s your favorite cosmic epoch?
When there's nothing left in final void of gloom, and not a quant brings any flash after the last, and nothing changes anymore, at all, and everything remains a pure chance of something that will never come.
well, not just one, the first second is my favorite. I can theorize about that non-stop without any scrupules, and the one thing that tends to disprove my theories, postulations, conjectures, thought processes, is "you forgot about conservation" or "you forgot about heisenbergs uncertainty principle" or "nuh-uu-uuuh, Pauli's exclusion dude" but never "not theoretically possible" or "that doesn't even sound like physics to me"..... or people just won't answer, that happens most of the time. Anyway, i'm not a big fan of string theory, which basically sounds like quantum field theory, only it's strings instead of fields, and everything else "oh, let's invent a couple more dimensions, it's perfectly fine!" Then again, for the past couple of months, i'm having the feeling that we are forgetting about one very important field. If GUT is correct, everything did separate from a unified force, then shouldn't that be a field too, when forces were still unified, or is that called a barn in physics? Something has to be responsible for raw energy, or how shall I call whatever the universe was before there was any matter at all, to be converted in different kinds of fields. We have no problem with gravity separating from that field, the strong force separating from that field, the weak and electromagnetic force separating from that field, but somehow, when we thought "hmmmmm, all forces are separated, so the field must have vanished".... and then we claim quark fields, electron fields, muon fields, tau fields,.... all other particles that DON'T have spin 0,1 or 2. My thought was "hmmmm, maybe that field is still there, and it just converts energy into bosons at high temperatures and fermions at low temperatures" It didn't even cross my mind, that I'm postulating something that was or is already there, and physicists are looking desperately for a TOE, both basically have the same objective. I'm saying that before the big bang the universe was zero-dimensional, cold and extremely dense, and inside that dimension is where gravity separated, turning a zero-dimension into spacetime
@@florh Flor, you are free to theorize anything, but Heisenberg's uncertainty principle is something that must be there in the very first structures of changes of our universe
Thank you for attaching faces with all the scientists' names. I've heard these stories so many times, but seeing some of their faces for the very first! Makes the video ten times more interesting for me, personally.
@@ameenabdullah5370 Because it's far more entertaining to watch a video of an interesting person with animations to look at rather than staring at a text.
Just brilliant as always. As I rewatched, it struck me how the description of the genesis and evolution of dark matter and dark energy is completely absent in our models of the first few seconds of the universe, since we have no clue what they are. It just shows how much we still have to learn!
Oh I'm pretty sure that's because dark matter/energy either didn't exist then or weren't in the right conditions to behave how they do now Sorta like how electrons couldn't bind to form matter until the universe had cooled for 380,000yrs
Cosmology and physics always fascinates me even if I'm not able to fully grasp all the complexities that comes with it, so I always enjoy listening to your videos that explains these concepts in a way that even an average person may be able to appreciate and share in the fascination of our vast universe in its mysterious ways. Yet the more I learn about Dark Matter and Dark Energy the more I can't help but feel like they don't exist. I can't help but feel as though they are derivative (or simply a placeholder of sorts) due to our lack of a more comprehensive understanding of how gravity affects the very fabric of our reality (ie space-time) at different scales. We only know how gravity 'acts' as an attractive force between bodies of mass through the warping of space-time, but how do we know that gravity is not 'acting' as a repulsive force over vast stretches of empty space through some negative warping/expansion of space-time? Since gravity isn't really a force but really a manipulation of the very fabric of our reality itself. We as humans living on planet earth, how would we know how space-time would pass by differently in inter-galactic space where there's hardly any matter? We can only perceive a reality in our frame of reference which is itself affected by gravity of our planets, moon and star. I have no evidence to base any of this on, but I can't help but have all these unanswered questions about the nature of our reality.
He lies without using the scientific method. Nothing prove what happened before the CMB radiation. Energies could collide and make the matter within existing space.
I find all these hypothesis fascinating! It is refreshing to see honest science educators when they acknowledge the limitations and speculatory nature of their claims.
That's because the matter/antimatter model for the big bang is just one of many and it doesn't even make sense Physicists prefer the energy model for the singularity The universe was too hot for matter to exist at the time of the inflation. Electrons need a specific temperature to have the properties they have now. The universe had to cool for 380,000yrs after the inflation epoch ended before electrons could bind to nuclei and form hydrogen atoms In the matter/antimatter model for the big bang no explanation is given for why the matter/antimatter was able to stay formed at those temperatures, nor does it explain where the matter that survived the bang went or which kind of matter it was The matter/antimatter model precludes our knowledge of the process of nucleosynthesis which is how matter actually first formed
Dear Mr Ash. You are the gift from the universe. If only you were my science teacher back in the days.. i can’t even say how much you taught me and I’m 36 🤓🥰🥰😘😘😘
Another awesome video thank you so much! I have a question, it’s always slightly confused me how the initial universe expanded and didn’t turn into a black hole. At the earliest moment of the universe, you said all the energy in the universe would be condensed to a swimming pool. But wouldn’t that high of an energy density form an inescapable force of gravity? Thanks!
At the risk of embarrassing myself, my understanding is that black holes form within the universe as the result of gravitational aberrations. At the point described, the dense, hot structure WAS the universe, not a structure within the universe. In addition the necessary forces such as electromagnetism and gravity had not established yet. Thus the universe could not form a black hole because it had nowhere to form it in, and the contents of the universe could not form a black hole because it lacked the structure that the forces impart and impose on the universe. However your speculation does yield fruit - it is believed that the early universe did create black holes that were not a result of star collapse - primordial black holes. In addition, a hypothesis called "cosmological coupling" proposes that the the expansion of the universe causes an increase in the mass of objects, and since black holes are already so massive, this coupling provides a shortcut for smaller black holes to become larger, even supermassive black holes without necessarily increasing their mass by consuming mass.
this was a beautiful exposition, thank you. The concept that all the universe could have started in a tiny space because it was not massive, it was energy, is a brilliantly obvious and simple explanation.
Tiny space is a way of putting it into words that we can understand but using a reference we connect with now, the "explosion" was the creation of space (and size) itself
I have heard his story more than several times, and I believe yours is the best rendition. And thank you for pointing out that singularities may/probably don't exist - most will avoid this note. As always: nicely done. I do have a question: When you say the very early universe was only 'energy', what does that mean? Is energy a thing in itself? I thought I understood that energy is a property of 'things'.
Great presentation that answered some questions. I appreciated the Einstein field equation section describing energy (includes mass) creating curvature. I'd like to know more about how (and if) the gravitational field translates to spacetime. Thank you!
OMG! Not to pander but this is great work and an awesome overview of the most important stages of the universe. It’s also well organized into history, theory, math, and imagery. I understand why it wouldn’t necessarily fit to include the separation of the strong-electroweak force and the antimatter problem, but hopefully you’ll allow me to ask some questions about it, as my spacetime cells idea postulates that it was here that matter was slightly favored over antimatter and that what we call dark matter was “formed”, but I think it’s residual virtual energy stuck in the W boson field. The question is: Does the W boson of the weak force only control flavor changing of quarks and why does it only occur in free neutrons and unstable nuclei?
Hey Arvan, Great Video! At high enough energy levels when the strong force was not working, and i also know that the electroweak video you did where you explain that the forces merge together into 1 force, what does that mean for the quantum fields? Are they merged together as well? Are the bosons that mediate the fields identical and when the energy drops they become different? Can you explain some more info on what a merged theory means for the behaviour of the particles? Do both forces still work the same with different strengths or both forces disappear etc? Thanks so much again!
Hello. Means that perhaps the universe was compacted into a little too dense, not really moving much chunk of anything that we could name something like that. Then, something happened and it expanded. Quickly. When that happened, possibly the forces manifested for the first time in this universe at least.
Dear Mr. Ash, first of all, thank you so much for the great content you provide on this amazing channel! Second, a question. I seem to remember a video about the beginning of the universe. The hypothesis in this video describes the universe not condensed in one single point -as far as I can remember- but was a zero average distribution of sub-elementary particles, there was a constant balance between creation and annihilation. I feel like remember this video is one of yours, but I am wrong or I am unable to find it. Can you please help me? Many thanks in advance! With best regards.
It is a matter of sorrow,😭🥺😭 that these great channels does not get vast subscribers like the other channels,,, like gaming channels, TV serial channels, entertaining channels, songs channel and so on. The most subscribed channels we see in UA-cam,, most of them are of no use. They are just entertaining and time killing, but do not give us any knowledge especially about science. Channels like these, which can be the light of education in our life, children's can be curious and motivated to be scientist in the future which can lead our humanity to the next level.... are not treated well... I love your channel and hope that you and other channels like yours might be the biggest channels of subscribers, viewers, and likes...... Wish you to be successful on your path to create new contents...... Love you🥰❣️❤️🇧🇩🇧🇩🇧🇩
At 1:20 you show the GR equation with Lambda on the right side. I like it moved over there so there is geometry on the left and stuff on the right. However, on the right side it takes a negative sign, not positive.
Dr. Ash This may be a naive question, but here it is. Since space and time was expanding in the first (incredibly) small fractions of a second at the beginning of our universe, how does it make sense to describe the expansion in terms of fractions of a second i.e. a zepto second or as you say, for example, or "ten to the minus 32 seconds" Since space-time itself is expanding, what is "ten to the minus 32 seconds?" How do physicist make that determination?
I might be too high for this but I'll try to explain You know how time moves faster in space for the international space station and how time moves slower near black holes? That's cause mass bends spacetime. We use our measurements of the time difference on earth/In orbit + physicists calculations of the number of particles in the universe (most of which have mass) to approximate how quickly time would flow if you got all the particles back in close proximity like they were during the inflation Because all the mass was super close together and gravity didn't exist (the four fundamental forces 'decayed' from the inflation quantum field) they had to try figure out how time would work without gravity by using our knowledge of how mass effects space It's all SUPER speculative and as such should be taken with a single atom of sodium and a single atom of chloride
I have a question to Mr Arvin.. If the earliest universe was only pure energy, how could it be hot and say the temperature was very high when there was nothing except energy to manifest "temperature". Temperature is defined as the kinetic energy of "particles" meaning "mass". I even fail to understand how the earliest universe ( just after a Plank's time , and plank's volume(4D) can be "hot". I would say it had a large potential enegery to produce heat by transformation if there was something created to jiggle and raise in tempersture and thus become "Hot". I also noticed that Einstein's GR does not have "temperature" in its equation, meaning gravity and engery are temperature agnostic. Correct me if I am wrong.
Great stuff. 36 years ago my boss at the NAS said his only regret about dying was missing out on all the stuff that would later be discovered. He was 42 at the time. I am now 70 and I understand what he means. For curious folks there's never enough time. 😢
I find it mind-blowing to think how many other intelligent civilizations that have appeared and disappeared already before our timeframe,.came this close to figuring out how everything started in the nature of our reality, and how many civilizations came to understand a lot more than we do right now (or will in the future or during our time as species here)
I wonder if it is correct to talk of temperature at the big bang - if it is massless energy, so how would we define temperature/motion of particles? Maybe we should just talk of energy density, or is this equivalent?
thank you for the interesting video. well explained and shown. I still don't know how to visualize the shape of the universe. if we see the CBR everywhere we look, would that means that we are inside a balloon that keeps getting inflated? But do we also say that the universe is flat?
There is no edge to the universe. In the balloon analogy, the universe would be the surface of the balloon. The balloon gets larger, but there is no edge.
If the Higgs is in a non-zero ground state and it's the coupling with it that makes particles drop to the zero ground state, does the Higgs still have potential to drop to the zero ground state? I mean is vacuum decay still a theoretical thing?
could the big bang be a singularity decay? past neutron decay, if photons decay, it would have to be a bifurcation into matter and antimatter, which if not energized by an outside source, gravity would push them back together which would make a heck of a bang... this is the second of ur vids that i have watched and liked : ), looking forward to the next
Cool! Awesome! Beautiful! *_Nothing_* beats the greatest brainchild of the human brain-the scientific method, whose solid yet pliable backbone is the fusing of constructive criticism, rigorous skepticism, a vivid imagination, and above all the consuming curiosity of a child. 💕☮🌎🌌
Hi Arvin, I understand that galactic expansion explains the famous red shift but one thing confuses me. A blue photon leaving a remote galaxy arrives at the earth as a red photon.. - A blue photon has more energy than a red photon - where has this energy gone ?
Good question. The photon doesn't gain or lose energy. The difference in energy arises because the observer’s reference frame is not the same as the reference frame that emitted the photon. It is due to cosmic expansion which creates a Doppler effect. Energy is not conserved from the perspective of different reference frames. For example if you were flying in a supersonic jet next to a fired bulled. You could simply grab that bullet with your hand. It would have no kinetic energy from your reference frame.
Neutron decay cosmology Dark matter is decayed free neutrons. Although it will evolve into atomic hydrogen initially it doesn't have a stable orbital electron so can't emit or absorb photons. The volume increase from this decay, near point particle to one cubic meter of gas, is a volume increase of 10^45. This is the expansion of dark energy. The negative pressure created by the electrons created from free neutron decay. The neutrons came from an event horizon somewhere. Matter/neutrons contact an event horizon become the vacuum flux for a single Planck second then reemerge from lowest energy density points of space where quantum basement is easiest to penetrate. Neutron decay cosmology
The universe was cooling and still is! So, where the heat was/is going? Was(is) it getting converted into particles or other forms of energy? Was the temperature low, in the quantum states where the particle formation probability was high? Did not read all the comments, if any body has raised/answered this. Finally, am I making any sense here? It had been great experience watching these videos on this channel. Dr Arvin Ash always triggers a different thought or two, with each video. Thanks to you ...
The universe is cooling because a volume (the entire universe in this case) is more energetic the smaller it is. More pressure = higher temps. All the energy from the big bang is still around, it's the volume (space) that is expanding. Coincidentally enough, that expansion will theoretically lead the entire universe to reach 0 Kelvin in an event called the big freeze. There are other theories like the big crunch where the universe ends in a very hot contraction, but that is more theoretical, and mostly based on the idea that our universe clearly began as a hot dense singularity. It's "more symmetrical" as it allow an explanation for the big bang, but with no certainty just yet
The interesting thing about the cosmological constant (CC), Einstein introduced it because his field equation was showing an expanding universe. So he introduced the CC to keep the universe in a static state. When it was discovered the universe was expanding, in the 1920s, he called it "his biggest blunder". Even when Einstein is wrong, he's right. Lol...
You are saying that the strong force began at a certain point, like it didn’t exist prior to that point. Do you mean that it did not exist at all before that time, or do you mean that it technically always did exist, but because of the immense amount of energy, it was basically negligible, because it would create continuously unstable bonds, but later when the energy density got lower, it was able to settle in stable bonds for prolonged amounts of time?
Yes, pretty much. It is thought at extremely high temperatures just after the big bang (tiny fractions of a second) all the forces of nature had the same strength (eg. the electromagnetic and weak forces combined above a thousand trillion degrees and before a trillionth of a second , electroweak fields increase in strength with temperature until they become as strong as the strong force, and all forces combined at a temperature of 10^28 degrees) due to the huge energy densities and the particle fields behaved differently than they do today, so quarks and electrons may have been undistinguishable.
I dont know but i believe that sound, a logical medium (waves), particles (that travel along waves...ie...light) and vibration (dependant on reverberation) explains that there must have been more than just One Big Bang and that there will be more big bangs to come. In fact, if you do the maths, we are currently still experiencing 3 concurrent big bangs (81st-84th total so far). It explains the macro (organism, destiny) behaviour of a cyclic time signature (yugas) that has already been recorded by our ancients...every pattern or complex light formation (irregular) seen in our universe can explain results of this theory.....either way, the intention or reason for all this is order.
Arvin Ash does a competent job of presenting a summary of standard cosmology within a 20-minute window. It was clear enough that I have no belief in the long-term value of standard cosmology. Presumably, the beginning of the Universe will involve an epic exchange of all four known forces of the Universe: the strong force, the weak force, electromagnetism and gravity. These are all field theories. The one field equation shown was that of General Relativity. GR has nothing to say about the strong force. GR has nothing to say about the weak force. GR has nothing to say about electromagnetism. GR will help with gravity but absolutely nothing else. This is not a minor problem, it is foundational. Do I expect cosmologists to admit such a fundamental problem? Of course not, they need to keep their research projects alive. We have much to learn. You can expect other efforts to repackage this information. When something is flawed, repackaging will not fix the problem. I will remain relaxed about cosmology. We have some most excellent data. We will need better math models, one that relies on something considerably richer than GR. Every theory has its limitations, and GR is limited to gravity. I will wait for something richer.
What fascinates me the most is time's utter and complete meaninglessless outside of our lifetimes. I may be at awe by the unbelieveably extensive lengths of time that came before my birth, even more by the mind-boggling lengths of time coming after my death, yet to my consciousness, these two periods will be and feel no longer than the blink of an eye of a plank-sized ant. For all I know the whole universe might reboot (some-unexplicably-how get completely destroyed and then spontaneously rebuilt with the same configuration after said reboot) daily, hourly, at every second, and I might not even notice it at all. It's like a brain f*ck on endless loop. But I kinda like to think about it.
Not too long ago we didn't know atoms existed. The more I learn about the universe the more I see how simple it is. From it's birth, to today. There's definitely gradual steps from simple to more complex. The universe is basically an ocean of empty space for stars and it's planets with dark energy as a one way current. Life is probably the natural chain reaction on planets with the right conditions. Starting out simple to consume energy and survive into more and more complex things to do basically the same thing.
Superb video. A bit disconcerted as i note the word quantum mechanics (QM) not associated with the cosmological description. By the looks of it the initial epochs all seem QMey rather than classical physical. Did the weirdness of QM play a role in these epochs? Was the entire big bang possibly due to QM?THANKS
I wonder if closer galaxies (means newer data) run away slower then farther galaxies (means older data) then does not it mean that extantion is slowing down?
I'm confused. You began by showing that gravity is not a force but is manifested by the curvature of space-time. But later when talking about the formation of galaxies you describe how the force of gravity pulls matter together. It would be clearer if you describe how space-time began to curve which cause matter/energy to clump creating more curvature...
if energy can neither be created nor destroyed and it can only be converted from one form to another. where do our energy as a soul or as a consciousness go once we die? or from where is this energy recycling? how exactly do some amalgamation of cells develop consciousness? (idk if this became a scientific or philosophical question but i need to know)
I think it all comes down to 3 questions everyone interested in science would so much like to find or hear the answer to : what are the dark energy and matter, what was the universe like at its "singularity", what is the quantum description of gravity if there can be any. But I think one step closer to all this is understanding what was the grand unification era like, when all forces except gravity were unified (I gotta say the electroweak force makes already no sense for me, how could light/electricity/magnetism and nuclear disintegration be the "same exact thing" at some point lol)
I don’t like it when a set of propositions is presented as if it is a proven description of facts. I like it when observations are shown to have led to propositions and these propositions have been thought over and over again and tested. Then they led to new propositions and new observations and new questions etc etc. If any mistake has been made either in the observations or the propositions the whole story may take a different turn and that is what the scientific method of understanding is all about.
It's the best scientific explanation of what we currently understand. When you say "proofs" - this really doesn't have a meaning in science. Everything is always under scrutiny. If you want to call the hundreds of observations that support the Big Bang Model proof, then we have hundreds of "proofs."
Amazing video! But i still don't get the time measures on the different stages of the Univers. Is it measured from within the system or converted to our perspective as external observers from our actual time?
Yea same, I did not get that part at all. Something happens within fraction of a second, then something after few minutes and the next stage is already hundreds of thousands of years. If space and time are so connected then do we really have a clear understanding at what pace time is progressing forward when the universe is only the size of a swimming pool?
#AskArvin Hi Arvin, thank you for yet another great presentation. You are the intellectual Mozart to my ears! My question is what is the possibility that the unseen mass, dark matter, would be coming from the fourth or higher spatial dimension? Is that too wild a thought? Do other dimensions not exist or do they? How are we sure of either? The best explanation on extra dimensions that I have seen has come from late Dr. Sagan in his iconic TV series Cosmos. He explained how an Apple slicing through a 2 dimensional world would appear like a train of slices changing shapes to the 2D citizens. A 4D (5D if you count time) world could exist right around us or may be at astronomical scale and would be casting gravity on our galaxies.
There is really no need to invoke an unseen dimension when it comes to dark matter. Just because we haven't detected what it is, does not mean that it is a product of anything other than our universe. There is no evidence of any spatial dimensions beyond the 3 we can see.
I don't understand how the CBR continues to be detected. It did not come from a continuous "engine" like light from the Sun. What makes it continuous? Can anyone help me with this?
Great video! Amazing! Just a little question. What about the size of our universe? It looks like our universe has a finite volyme when I look att the video but sometimes physicists claim the it is infinite. What do you think about it? I´m not talking about the visible universe but the whole of it.
@@debrachambers1304 correct, there is a minimum size (which is much larger than we can see) but no way to tell if it is just really big or infinite. So far.
If the universe expands and has been expanding since the big bang, which is a better building block of spacetime? A. superstrings. B. quantum loops. C. Huygen Principle (ripples). D. Nothingness. Answer: C.
Really, we can't thank you enough, Arvin. Your work makes complex--vitally important--ideas available for all. There is no better definition of a great teacher.
Thank you for that. Much appreciated!
Thanks!
Thanks so much.
The explanation at 7:05 regarding how the sizing of the early universe is possible is just fantastic - I haven't heard it explained that way - thank you
Makes sense.
There isn't any expansion, it is only depletion of the energy of the light beams from very old spots of images of the galactic sources by the Laws: of Wien and Planck 's λ=σ/Τ, λ= ch/E. When the T and the E goes to 0 the λ goes to infinity. It is simple physics! The galaxies sources aren't still in a spot to supply with energy their old images. They are traveling over trajectories and if they exist nobody now could see their real images.
@@user-dialectic-scietist1 Wrong, there is expansion and has being proven. The Wien law does not account for the red shift of the spectrum of distant galaxies.
@@shadowmax889 And what about the Planck's Law? And why, please the law of Wien do not account? You mean that in one Galaxy, the temperatures of its stars are the same? The Wien's law is a universal law and with this law an Astronomer can tell you the temperature of a star be the color in the spectrum. That means, far away red, to cold. Because you do not like the answer, you can't through the law away. And the Wien law is going well with the law of Planck. I am translating my books in English now, and I have written there 15 points why the expansion is nonsense. Especially about space and time if they are the energy of the vacuum, they can't expand at velocities greater than c. The dogma of Einstein says, no material, no energy with speed greater than c. Furthermore, my friend, space and time couldn't create a traveling fabric, because from SR, they are opposite values. When space dilates, the time has to shrink, and Vice Versa. The expansion is impossible under any known physical law. Accept someone write new physics, but then everything we know about physics has to be thrown away. So, find an answer about Planck's law, and you said that it is proved the expansion. Please tell me where I can read about a proof, because it is light and only human eye.
@@user-dialectic-scietist1 What about Plank's law? The same because it does not explain the red shift in SPECTRUM.
Wein and Plank's law are about the black body radiation and measure the temperature of stars, the thing is those laws do not explain the red shift in the spectrum of elements that make the distant galaxies. The spectrum of any element do not depend on the temperature, but the orbitals of its electrons. So if you have a galaxy with the spectrum of the hydrogen red shifted is not because it is colder, but because is moving away from you, the same thing goes if the spectrum is blue shifted, the galaxy is moving towards you.
The expansion of the universe has being proved beyond doubt and do not violate Relativity (it was the derivation of the relativity equation that hinted to an expanded universe in the first place).
Objects cannot move faster than C trough space, but space itself CAN expand beyond C, that's why the expansion of the universe do not violate relativity no need to any new law.
The only question scientist are looking for an answer is not that space is expanding but is expanding at accelerated rates, and that is a mystery right now
Love seeing the most fascinating discoveries in science made by my colleagues distilled into such delicious knowledge nuggets! What’s your favorite cosmic epoch?
When there's nothing left in final void of gloom, and not a quant brings any flash after the last, and nothing changes anymore, at all, and everything remains a pure chance of something that will never come.
well, not just one, the first second is my favorite. I can theorize about that non-stop without any scrupules, and the one thing that tends to disprove my theories, postulations, conjectures, thought processes, is "you forgot about conservation" or "you forgot about heisenbergs uncertainty principle" or "nuh-uu-uuuh, Pauli's exclusion dude" but never "not theoretically possible" or "that doesn't even sound like physics to me"..... or people just won't answer, that happens most of the time.
Anyway, i'm not a big fan of string theory, which basically sounds like quantum field theory, only it's strings instead of fields, and everything else "oh, let's invent a couple more dimensions, it's perfectly fine!" Then again, for the past couple of months, i'm having the feeling that we are forgetting about one very important field.
If GUT is correct, everything did separate from a unified force, then shouldn't that be a field too, when forces were still unified, or is that called a barn in physics?
Something has to be responsible for raw energy, or how shall I call whatever the universe was before there was any matter at all, to be converted in different kinds of fields.
We have no problem with gravity separating from that field, the strong force separating from that field, the weak and electromagnetic force separating from that field, but somehow, when we thought "hmmmmm, all forces are separated, so the field must have vanished".... and then we claim quark fields, electron fields, muon fields, tau fields,.... all other particles that DON'T have spin 0,1 or 2. My thought was "hmmmm, maybe that field is still there, and it just converts energy into bosons at high temperatures and fermions at low temperatures"
It didn't even cross my mind, that I'm postulating something that was or is already there, and physicists are looking desperately for a TOE, both basically have the same objective.
I'm saying that before the big bang the universe was zero-dimensional, cold and extremely dense, and inside that dimension is where gravity separated, turning a zero-dimension into spacetime
@@florh Flor, you are free to theorize anything, but Heisenberg's uncertainty principle is something that must be there in the very first structures of changes of our universe
Inflation
The habitable age, when the entire universe was a comfortable 70F
All cosmology beautifully and effectively summarised. Everyone should see this video.
Thank you for attaching faces with all the scientists' names. I've heard these stories so many times, but seeing some of their faces for the very first! Makes the video ten times more interesting for me, personally.
...why? It's not even the focus at all of the video. You know you can just Google what any scientist looked like, right?
@@ChinnuWoW you can Google anything ,Why did you come here ?
@@ameenabdullah5370 Because it's far more entertaining to watch a video of an interesting person with animations to look at rather than staring at a text.
Just brilliant as always. As I rewatched, it struck me how the description of the genesis and evolution of dark matter and dark energy is completely absent in our models of the first few seconds of the universe, since we have no clue what they are. It just shows how much we still have to learn!
Oh I'm pretty sure that's because dark matter/energy either didn't exist then or weren't in the right conditions to behave how they do now
Sorta like how electrons couldn't bind to form matter until the universe had cooled for 380,000yrs
Thank you, Dr. Ash. Time spent with you is always the best part of my day. Another one of your superb programs.
Gravitational waves didn't provide evidence for Cosmic Inflation. Arvin Ash lied in this video.
Thanks a lot sir for explaining complex issues in simple and lucid manner.
Amazing that we've come this far in our knowledge, and there's still so much more to learn
you know, I'm so glad to have a person that teaching something to me from my cell phone. I love the developments in the age I was born.
Congrats as always doc. Great video and clear information, thanks again and greetings from Athens, Greece.
Cosmology and physics always fascinates me even if I'm not able to fully grasp all the complexities that comes with it, so I always enjoy listening to your videos that explains these concepts in a way that even an average person may be able to appreciate and share in the fascination of our vast universe in its mysterious ways.
Yet the more I learn about Dark Matter and Dark Energy the more I can't help but feel like they don't exist. I can't help but feel as though they are derivative (or simply a placeholder of sorts) due to our lack of a more comprehensive understanding of how gravity affects the very fabric of our reality (ie space-time) at different scales. We only know how gravity 'acts' as an attractive force between bodies of mass through the warping of space-time, but how do we know that gravity is not 'acting' as a repulsive force over vast stretches of empty space through some negative warping/expansion of space-time? Since gravity isn't really a force but really a manipulation of the very fabric of our reality itself. We as humans living on planet earth, how would we know how space-time would pass by differently in inter-galactic space where there's hardly any matter? We can only perceive a reality in our frame of reference which is itself affected by gravity of our planets, moon and star. I have no evidence to base any of this on, but I can't help but have all these unanswered questions about the nature of our reality.
Best 20 minutes I'll have today, no doubt! Thank you Professor Ash! I've not seen the "Big Bang" Cone drawn to include the Higgs Field before!
He lies without using the scientific method. Nothing prove what happened before the CMB radiation. Energies could collide and make the matter within existing space.
I find all these hypothesis fascinating! It is refreshing to see honest science educators when they acknowledge the limitations and speculatory nature of their claims.
arvin you are THE expert in explaining the unexplainable in simple terms
Thanks for creating this program. Always great to watch. I didn't see anything about the imbalance of matter / anti-matter in this program.
That's because the matter/antimatter model for the big bang is just one of many and it doesn't even make sense
Physicists prefer the energy model for the singularity
The universe was too hot for matter to exist at the time of the inflation. Electrons need a specific temperature to have the properties they have now. The universe had to cool for 380,000yrs after the inflation epoch ended before electrons could bind to nuclei and form hydrogen atoms
In the matter/antimatter model for the big bang no explanation is given for why the matter/antimatter was able to stay formed at those temperatures, nor does it explain where the matter that survived the bang went or which kind of matter it was
The matter/antimatter model precludes our knowledge of the process of nucleosynthesis which is how matter actually first formed
@@drsatan7554 thanks for the detailed reply. Appreciate your message... Very insightful for me
What a great show. I've watched this episode now about 6 or 7 times, and I learn something new everytime.
Dear Mr Ash. You are the gift from the universe. If only you were my science teacher back in the days.. i can’t even say how much you taught me and I’m 36 🤓🥰🥰😘😘😘
Another awesome video thank you so much! I have a question, it’s always slightly confused me how the initial universe expanded and didn’t turn into a black hole. At the earliest moment of the universe, you said all the energy in the universe would be condensed to a swimming pool. But wouldn’t that high of an energy density form an inescapable force of gravity? Thanks!
At the risk of embarrassing myself, my understanding is that black holes form within the universe as the result of gravitational aberrations. At the point described, the dense, hot structure WAS the universe, not a structure within the universe. In addition the necessary forces such as electromagnetism and gravity had not established yet. Thus the universe could not form a black hole because it had nowhere to form it in, and the contents of the universe could not form a black hole because it lacked the structure that the forces impart and impose on the universe.
However your speculation does yield fruit - it is believed that the early universe did create black holes that were not a result of star collapse - primordial black holes. In addition, a hypothesis called "cosmological coupling" proposes that the the expansion of the universe causes an increase in the mass of objects, and since black holes are already so massive, this coupling provides a shortcut for smaller black holes to become larger, even supermassive black holes without necessarily increasing their mass by consuming mass.
this was a beautiful exposition, thank you. The concept that all the universe could have started in a tiny space because it was not massive, it was energy, is a brilliantly obvious and simple explanation.
Tiny space is a way of putting it into words that we can understand but using a reference we connect with now, the "explosion" was the creation of space (and size) itself
I have heard his story more than several times, and I believe yours is the best rendition. And thank you for pointing out that singularities may/probably don't exist - most will avoid this note. As always: nicely done.
I do have a question: When you say the very early universe was only 'energy', what does that mean? Is energy a thing in itself? I thought I understood that energy is a property of 'things'.
What a Fantastic video! One of the Best I've seen to quickly explore cosmology. 👍🏻
Another great video. Thank you, Arvin.
Great presentation that answered some questions. I appreciated the Einstein field equation section describing energy (includes mass) creating curvature. I'd like to know more about how (and if) the gravitational field translates to spacetime. Thank you!
The gravitational quantum field IS spacetime. At least I'm fairly certain
I like it, sharp work simplifying decades.
Thank you for this concise summary.
Another beautiful lesson thank you very much Arvin
Arvin, the explainer and presenter par excellence.
This is crazily good presentation! thank you
OMG! Not to pander but this is great work and an awesome overview of the most important stages of the universe. It’s also well organized into history, theory, math, and imagery.
I understand why it wouldn’t necessarily fit to include the separation of the strong-electroweak force and the antimatter problem, but hopefully you’ll allow me to ask some questions about it, as my spacetime cells idea postulates that it was here that matter was slightly favored over antimatter and that what we call dark matter was “formed”, but I think it’s residual virtual energy stuck in the W boson field.
The question is: Does the W boson of the weak force only control flavor changing of quarks and why does it only occur in free neutrons and unstable nuclei?
Wow....thanx for compilation of timeline 🤩
love you sir 😍😍.......thanku for this channel...... please never stop making videos like this
I like how you broke it down for us. Great content!
It's so crazy that we have made this discoveries in the last 100 years
Amazing work, thank you sir.
as always great content and nice speech
your videos are the best
Love the vid thank you. But…. Where did the singularity come from? and where did the void come from? Is anything real?
This is not understood, and is a gap in our understanding.
Hey Arvan, Great Video! At high enough energy levels when the strong force was not working, and i also know that the electroweak video you did where you explain that the forces merge together into 1 force, what does that mean for the quantum fields? Are they merged together as well? Are the bosons that mediate the fields identical and when the energy drops they become different? Can you explain some more info on what a merged theory means for the behaviour of the particles? Do both forces still work the same with different strengths or both forces disappear etc? Thanks so much again!
Hello.
Means that perhaps the universe was compacted into a little too dense, not really moving much chunk of anything that we could name something like that.
Then, something happened and it expanded. Quickly.
When that happened, possibly the forces manifested for the first time in this universe at least.
Dear Mr. Ash,
first of all, thank you so much for the great content you provide on this amazing channel!
Second, a question.
I seem to remember a video about the beginning of the universe.
The hypothesis in this video describes the universe not condensed in one single point -as far as I can remember- but was a zero average distribution of sub-elementary particles, there was a constant balance between creation and annihilation.
I feel like remember this video is one of yours, but I am wrong or I am unable to find it.
Can you please help me?
Many thanks in advance!
With best regards.
Na dawg. You jus high
Another great summation!!
Amazing graphics!
It is a matter of sorrow,😭🥺😭
that these great channels does not get vast subscribers like the other channels,,, like gaming channels, TV serial channels, entertaining channels, songs channel and so on. The most subscribed channels we see in UA-cam,, most of them are of no use. They are just entertaining and time killing, but do not give us any knowledge especially about science. Channels like these, which can be the light of education in our life, children's can be curious and motivated to be scientist in the future which can lead our humanity to the next level.... are not treated well...
I love your channel and hope that you and other channels like yours might be the biggest channels of subscribers, viewers, and likes......
Wish you to be successful on your path to create new contents......
Love you🥰❣️❤️🇧🇩🇧🇩🇧🇩
Amazing video. Thanks!
THANK YOU...
DR. ARVIN ASH...!!!
Good content
I’m also a Chem Eng and love cosmology & astrophysics!
Thanks for this masterpiece, Sir Arvin
At 1:20 you show the GR equation with Lambda on the right side. I like it moved over there so there is geometry on the left and stuff on the right. However, on the right side it takes a negative sign, not positive.
Wonderful and clear presentacion! I would like to know how life and consciousness fit into this, because without them the model is incomplete ...
Absolutly wonderful video!!! 🤩🤩🤩
Dr. Ash
This may be a naive question, but here it is. Since space and time was expanding in the first (incredibly) small fractions of a second at the beginning of our universe, how does it make sense to describe the expansion in terms of fractions of a second i.e. a zepto second or as you say, for example, or "ten to the minus 32 seconds" Since space-time itself is expanding, what is "ten to the minus 32 seconds?"
How do physicist make that determination?
I might be too high for this but I'll try to explain
You know how time moves faster in space for the international space station and how time moves slower near black holes?
That's cause mass bends spacetime. We use our measurements of the time difference on earth/In orbit + physicists calculations of the number of particles in the universe (most of which have mass) to approximate how quickly time would flow if you got all the particles back in close proximity like they were during the inflation
Because all the mass was super close together and gravity didn't exist (the four fundamental forces 'decayed' from the inflation quantum field) they had to try figure out how time would work without gravity by using our knowledge of how mass effects space
It's all SUPER speculative and as such should be taken with a single atom of sodium and a single atom of chloride
I have a question to Mr Arvin.. If the earliest universe was only pure energy, how could it be hot and say the temperature was very high when there was nothing except energy to manifest "temperature". Temperature is defined as the kinetic energy of "particles" meaning "mass". I even fail to understand how the earliest universe ( just after a Plank's time , and plank's volume(4D) can be "hot". I would say it had a large potential enegery to produce heat by transformation if there was something created to jiggle and raise in tempersture and thus become "Hot". I also noticed that Einstein's GR does not have "temperature" in its equation, meaning gravity and engery are temperature agnostic. Correct me if I am wrong.
Great stuff. 36 years ago my boss at the NAS said his only regret about dying was missing out on all the stuff that would later be discovered. He was 42 at the time. I am now 70 and I understand what he means. For curious folks there's never enough time. 😢
I find it mind-blowing to think how many other intelligent civilizations that have appeared and disappeared already before our timeframe,.came this close to figuring out how everything started in the nature of our reality, and how many civilizations came to understand a lot more than we do right now (or will in the future or during our time as species here)
20 Minutes well spent
I wonder if it is correct to talk of temperature at the big bang - if it is massless energy, so how would we define temperature/motion of particles? Maybe we should just talk of energy density, or is this equivalent?
thank you for the interesting video. well explained and shown. I still don't know how to visualize the shape of the universe. if we see the CBR everywhere we look, would that means that we are inside a balloon that keeps getting inflated? But do we also say that the universe is flat?
There is no edge to the universe. In the balloon analogy, the universe would be the surface of the balloon. The balloon gets larger, but there is no edge.
@@ArvinAsh ok. thank you, but still..but from where we are how can we look at any direction and still see up, down left and right (figuratively)
If the Higgs is in a non-zero ground state and it's the coupling with it that makes particles drop to the zero ground state, does the Higgs still have potential to drop to the zero ground state? I mean is vacuum decay still a theoretical thing?
Two minutes, can’t wait!
Are wave functions and light cones the same thing?
Or perhaps I should say is there a correspondence?
No. Two different animals. I have several videos on what wave functions are. Check them out.
could the big bang be a singularity decay?
past neutron decay, if photons decay, it would have to be a bifurcation into matter and antimatter, which if not energized by an outside source, gravity would push them back together which would make a heck of a bang...
this is the second of ur vids that i have watched and liked : ), looking forward to the next
Cool! Awesome! Beautiful!
*_Nothing_* beats the greatest brainchild of the human brain-the scientific method, whose solid yet pliable backbone is the fusing of constructive criticism, rigorous skepticism, a vivid imagination, and above all the consuming curiosity of a child. 💕☮🌎🌌
l love this channel, many thanks
Love it
When you see for example one second after Big bang what do you actually mean? Because time pass differently back then because it was so dense
@Arvin Ash could the Higgs field quantum tunneling to the present energy state have caused the big bang?
Hi Arvin, I understand that galactic expansion explains the famous red shift but one thing confuses me. A blue photon leaving a remote galaxy arrives at the earth as a red photon..
- A blue photon has more energy than a red photon - where has this energy gone ?
Good question. The photon doesn't gain or lose energy. The difference in energy arises because the observer’s reference frame is not the same as the reference frame that emitted the photon. It is due to cosmic expansion which creates a Doppler effect. Energy is not conserved from the perspective of different reference frames. For example if you were flying in a supersonic jet next to a fired bulled. You could simply grab that bullet with your hand. It would have no kinetic energy from your reference frame.
Neutron decay cosmology
Dark matter is decayed free neutrons. Although it will evolve into atomic hydrogen initially it doesn't have a stable orbital electron so can't emit or absorb photons.
The volume increase from this decay, near point particle to one cubic meter of gas, is a volume increase of 10^45. This is the expansion of dark energy. The negative pressure created by the electrons created from free neutron decay.
The neutrons came from an event horizon somewhere. Matter/neutrons contact an event horizon become the vacuum flux for a single Planck second then reemerge from lowest energy density points of space where quantum basement is easiest to penetrate.
Neutron decay cosmology
The universe was cooling and still is! So, where the heat was/is going? Was(is) it getting converted into particles or other forms of energy? Was the temperature low, in the quantum states where the particle formation probability was high? Did not read all the comments, if any body has raised/answered this. Finally, am I making any sense here?
It had been great experience watching these videos on this channel. Dr Arvin Ash always triggers a different thought or two, with each video. Thanks to you ...
The universe is cooling because a volume (the entire universe in this case) is more energetic the smaller it is. More pressure = higher temps. All the energy from the big bang is still around, it's the volume (space) that is expanding. Coincidentally enough, that expansion will theoretically lead the entire universe to reach 0 Kelvin in an event called the big freeze. There are other theories like the big crunch where the universe ends in a very hot contraction, but that is more theoretical, and mostly based on the idea that our universe clearly began as a hot dense singularity. It's "more symmetrical" as it allow an explanation for the big bang, but with no certainty just yet
Great video. Did you forget matter/antimatter annihilation? @Arvin Ash
The interesting thing about the cosmological constant (CC), Einstein introduced it because his field equation was showing an expanding universe. So he introduced the CC to keep the universe in a static state. When it was discovered the universe was expanding, in the 1920s, he called it "his biggest blunder". Even when Einstein is wrong, he's right. Lol...
Can You explain in telugu ?Add languages to video like Mr.beast most of the people will not understand english .
Thanks for your explanation Sir
You are saying that the strong force began at a certain point, like it didn’t exist prior to that point.
Do you mean that it did not exist at all before that time, or do you mean that it technically always did exist, but because of the immense amount of energy, it was basically negligible, because it would create continuously unstable bonds, but later when the energy density got lower, it was able to settle in stable bonds for prolonged amounts of time?
Yes, pretty much. It is thought at extremely high temperatures just after the big bang (tiny fractions of a second) all the forces of nature had the same strength (eg. the electromagnetic and weak forces combined above a thousand trillion degrees and before a trillionth of a second , electroweak fields increase in strength with temperature until they become as strong as the strong force, and all forces combined at a temperature of 10^28 degrees) due to the huge energy densities and the particle fields behaved differently than they do today, so quarks and electrons may have been undistinguishable.
I dont know but i believe that sound, a logical medium (waves), particles (that travel along waves...ie...light) and vibration (dependant on reverberation) explains that there must have been more than just One Big Bang and that there will be more big bangs to come. In fact, if you do the maths, we are currently still experiencing 3 concurrent big bangs (81st-84th total so far). It explains the macro (organism, destiny) behaviour of a cyclic time signature (yugas) that has already been recorded by our ancients...every pattern or complex light formation (irregular) seen in our universe can explain results of this theory.....either way, the intention or reason for all this is order.
He will be happy if you like and share his video🙂
Arvin Ash does a competent job of presenting a summary of standard cosmology within a 20-minute window. It was clear enough that I have no belief in the long-term value of standard cosmology. Presumably, the beginning of the Universe will involve an epic exchange of all four known forces of the Universe: the strong force, the weak force, electromagnetism and gravity. These are all field theories. The one field equation shown was that of General Relativity. GR has nothing to say about the strong force. GR has nothing to say about the weak force. GR has nothing to say about electromagnetism. GR will help with gravity but absolutely nothing else. This is not a minor problem, it is foundational.
Do I expect cosmologists to admit such a fundamental problem? Of course not, they need to keep their research projects alive. We have much to learn. You can expect other efforts to repackage this information. When something is flawed, repackaging will not fix the problem.
I will remain relaxed about cosmology. We have some most excellent data. We will need better math models, one that relies on something considerably richer than GR. Every theory has its limitations, and GR is limited to gravity. I will wait for something richer.
What does "infinitesimally small" mean if the singularity is the only thing that exists? With respect to what is it "small"?
That's a very good comment. It simply means that it was much smaller than the universe is today.
What fascinates me the most is time's utter and complete meaninglessless outside of our lifetimes. I may be at awe by the unbelieveably extensive lengths of time that came before my birth, even more by the mind-boggling lengths of time coming after my death, yet to my consciousness, these two periods will be and feel no longer than the blink of an eye of a plank-sized ant. For all I know the whole universe might reboot (some-unexplicably-how get completely destroyed and then spontaneously rebuilt with the same configuration after said reboot) daily, hourly, at every second, and I might not even notice it at all. It's like a brain f*ck on endless loop. But I kinda like to think about it.
Not too long ago we didn't know atoms existed. The more I learn about the universe the more I see how simple it is.
From it's birth, to today. There's definitely gradual steps from simple to more complex.
The universe is basically an ocean of empty space for stars and it's planets with dark energy as a one way current.
Life is probably the natural chain reaction on planets with the right conditions. Starting out simple to consume energy and survive into more and more complex things to do basically the same thing.
great job from a layperson like me love it
Superb video. A bit disconcerted as i note the word quantum mechanics (QM) not associated with the cosmological description. By the looks of it the initial epochs all seem QMey rather than classical physical. Did the weirdness of QM play a role in these epochs? Was the entire big bang possibly due to QM?THANKS
I wonder if closer galaxies (means newer data) run away slower then farther galaxies (means older data) then does not it mean that extantion is slowing down?
I'm confused. You began by showing that gravity is not a force but is manifested by the curvature of space-time. But later when talking about the formation of galaxies you describe how the force of gravity pulls matter together. It would be clearer if you describe how space-time began to curve which cause matter/energy to clump creating more curvature...
Great work
Love the universe
if energy can neither be created nor destroyed and it can only be converted from one form to another. where do our energy as a soul or as a consciousness go once we die? or from where is this energy recycling? how exactly do some amalgamation of cells develop consciousness? (idk if this became a scientific or philosophical question but i need to know)
It is arbitrary. We perceive it ourselves.
My dude, you do a service to society🙏
I think it all comes down to 3 questions everyone interested in science would so much like to find or hear the answer to : what are the dark energy and matter, what was the universe like at its "singularity", what is the quantum description of gravity if there can be any. But I think one step closer to all this is understanding what was the grand unification era like, when all forces except gravity were unified (I gotta say the electroweak force makes already no sense for me, how could light/electricity/magnetism and nuclear disintegration be the "same exact thing" at some point lol)
I don’t like it when a set of propositions is presented as if it is a proven description of facts. I like it when observations are shown to have led to propositions and these propositions have been thought over and over again and tested. Then they led to new propositions and new observations and new questions etc etc. If any mistake has been made either in the observations or the propositions the whole story may take a different turn and that is what the scientific method of understanding is all about.
It's the best scientific explanation of what we currently understand. When you say "proofs" - this really doesn't have a meaning in science. Everything is always under scrutiny. If you want to call the hundreds of observations that support the Big Bang Model proof, then we have hundreds of "proofs."
@@ArvinAsh you are right, but I would have liked to see that recognition of the scientific process reflected in your presentation.
Amazing video! But i still don't get the time measures on the different stages of the Univers. Is it measured from within the system or converted to our perspective as external observers from our actual time?
Yea same, I did not get that part at all. Something happens within fraction of a second, then something after few minutes and the next stage is already hundreds of thousands of years. If space and time are so connected then do we really have a clear understanding at what pace time is progressing forward when the universe is only the size of a swimming pool?
wonderful
I only wish this were 90 minutes- most of us who like these videos prefer long videos.
What is the difference between the big bang singularity and a kugelblitz? And how could a kugelblitz 'explode' so matter escaped from it?
#AskArvin Hi Arvin, thank you for yet another great presentation. You are the intellectual Mozart to my ears! My question is what is the possibility that the unseen mass, dark matter, would be coming from the fourth or higher spatial dimension? Is that too wild a thought? Do other dimensions not exist or do they? How are we sure of either? The best explanation on extra dimensions that I have seen has come from late Dr. Sagan in his iconic TV series Cosmos. He explained how an Apple slicing through a 2 dimensional world would appear like a train of slices changing shapes to the 2D citizens. A 4D (5D if you count time) world could exist right around us or may be at astronomical scale and would be casting gravity on our galaxies.
There is really no need to invoke an unseen dimension when it comes to dark matter. Just because we haven't detected what it is, does not mean that it is a product of anything other than our universe. There is no evidence of any spatial dimensions beyond the 3 we can see.
@@ArvinAsh Many Thanks Arvin. Kiitos (Finnish for thanks pronounced kee-tos)
Now I know that me having interest in cosmology is an investment for 150 billion years
I don't understand how the CBR continues to be detected. It did not come from a continuous "engine" like light from the Sun. What makes it continuous? Can anyone help me with this?
Great video! Amazing! Just a little question. What about the size of our universe? It looks like our universe has a finite volyme when I look att the video but sometimes physicists claim the it is infinite. What do you think about it? I´m not talking about the visible universe but the whole of it.
I don't think anyone knows
@@debrachambers1304 correct, there is a minimum size (which is much larger than we can see) but no way to tell if it is just really big or infinite. So far.
If the universe expands and has been expanding since the big bang, which is a better building block of spacetime?
A. superstrings.
B. quantum loops.
C. Huygen Principle (ripples).
D. Nothingness.
Answer: C.