The precise mathematical interpretation of the Cosmic Microwave Background proves conclusively that the Universe had no beginning has no limit in size and will not end.
I teach a high school astrophysics class and I rely heavily on this series to boost my understanding and help me translate difficult concepts to my students. I’m a much better - and more educated - teacher. Thank you Matt O’Dowd.
@Joe Mackenzie Should we just ban science in school then? Because the first rule of science - especially quantum physics and astrophysics is "If you think you understand it, you clearly don't."
@Tyler Boothman I agree; however, you shouldn't be teaching something if you rely "heavily" on anything else to boost your own understanding of it. It's like having a translator that doesn't really know the language they're translating..
you teach things to kids that you dont yourself understand? So you just regurgitate pbs spacetime to your students; without the understanding necessary to do so...kewwl
Its a weird learning curve, after watching all of his videos i have got to say, what little i have come to understand has just made me waaay more confused about the nature of reality than i was at the beginning. Every question answered is 10 new questions asked.
For everyone who's confused: I've been watching these videos diligently for years and they do a great job of scaffolding to get you to the point where you can actually understand this level of cosmology. Go back and rewatch each one as many times as you need, you'll get there! It helps to watch with a friend and try to explain what you understood from each video in your own words. LOVE to the SPACETIME crew! Thanks for making physics accessible to the rest of us!
I love how both Fermilab and Space time are using phase transitions of water to describe cosmology or neutrino physics concepts. It makes the material really easy to grasp.
I do hope that that "another time" for magnetic monopoles isn't too far into the future. I'm quite fascinated by the concept, but just can't wrap my mind around envisioning them. They're just _so_ foreign. I'd love to hear your explanation and walk-through of them.
What a legend, Alan Guth, his concept of the inflaton field is definitely onto something bigger. I got a serene feeling as he explained the re-thermalisation of the early universe. It makes so much sense, the decay of virtual inflaton particles to actual particle converting the potential energy to tangible forms and possibly leading to phase transforms in the inflaton field. Yes I have already watched the sequel video, but the fact that phase transforms can occur in the potential energy of field strengths is so cool, especially when everything heats up again ;) I guess the physical constants in nature would have been absolutely scewed at that initial point of the high energy inflaton field
Well done. You are becoming an expert in interpreting these concepts without the math and scientific lingo. Thanks and to all the staff who support you.
@Firebrand Give me a break, these are some of the best science related videos on youtube- and I would argue that Space Time drills down on its topics a lot further than many other documentaries. They always give you the feel of the math when its reasonable, and are quite good about using terminology. What would be the point of showing math that no one would understand? There were calculations I had to do in my physics courses that would take up multiple sheets of paper, its not really reasonable or feasible to expect them to show all the math involved with a lot of these concepts- it wouldn't do anything but distract and confuse. It's also totally feasible to understand at a practical level, many of these ideas in physics. That's like saying you need to know how to code in programming languages to be able to understand how to use a computer- sure, it gives you a lower level deeper understanding that could enrich your understanding of what is happening , but its not required. I have to be honest, math was always my least favorite part of physics and astronomy.
Problem is there's no way to really understand this stuff without the math. You're just being fooled into thinking you know more than you do. No offense of course.
@Justin The only reason this channel is better than the myriad of "DUDE WEED LMAO SPACE" tier channels or shows out there is exactly because (at least in some of the older videos I've watched) they actually show some of the basic math behind it (even if it's just a graph of a function), because it's absolutely necessary to understand anything at all beyond learning a bunch of terminology, something which a lot of people misintepret as having learned anything. There is absolutely no way around it if you want to actually understand some of it, even on a surface level. And no I am not a physicist.
Thank you for explaining how inflation implies a multiverse. I've heard Alan Guth and others mention this numerous times but never took the time to explain why. This is the first time I can take the notion of the multiverse seriously.
Once more a commendable presentation of a conceptually complex topic. Digesting obtuse specialist journal publications, then distilling them into talking points non-specialist might appreciate, then crafting those into a script and visuals able to communicate the obtuse; that is a commendable and rare accomplishment. Cheers!
These videos are amazing and you and your team are amazing. I admit I often needs to see them several times, but the universe has all my life been a corner stone. Arthur C Clark was my favourite science fiction writer. And I was lucky to live where it was without lights. Very north in Denmark. So my imagination was able to evolve. But as you I was very lucky to also be quite good to music, so my education was the classic and now (15 years ago) I really took my time to get the universe seriously back in my life. And you tube are a gold mine at knowledge and I use every available moment to catch up. So music and science do keep my young, unfortunately I do miss to have some to ping pongs theses complicated issues with. But I I’m happy to learn what new and fantastic things, and I’m so impressed how far we have been able to go, only in so short time. The only thing I’m worried about, how to reach quantum gravity or the theory of everything ( GUT) the math seems to be able to provide a solution,but how on earth can we measure, test or will we need to settle until we are able to measure multiverse etc. And another thing the missing mass and the acceleration of the universe. What an exciting time. I surely hope I will live long enough to see some solutions .
Hey guys. Just discovered your channel this is really awesome, thank you!! I have a question: I read about our own supermassive black hole increasing its radiation in the last months, how are we measuring this over such distance?
Thanks for the crisp and very informative episode!! I was just about to finish the book written by Alan Guth’s The Inflationary Universe and your episode served as a summarization of it!!
Love this channel! Can you do an episode about Saturn's rings please? An idea for possible future episodes: It would be cool to learn about some historical theories that have been debunked or abandoned, and why. For example, Tachyon particles Aether theories Various Planet X theories, etc.
9:30 Or a minor perturbation (flick the bottle with your finger). This perturbation causes a wave of higher density to traverse the supercooled water with a region behind the wave being even colder. This can cause a small ice crystal to form, which then slowly moves across the container freezing the rest of the water.
I'm still unsure how we talk about "time" in the early universe and I often feel like this gets brushed aside in these kinds of descriptions. We say that certain things happened at certain points in time, but since time is inextricably linked to space, then surely the "amount of time" that the universe experienced inflation can't be so trivially described? Doesn't the expansion of space itself influence the description of time in that space? If so, then perhaps it's relatively inconsequential under Hubble expansion, but surely under inflation the effect must be noticeable. Or am I thinking about this all wrong?
@Frank Schneider the participation of physicists in biology has revolutionized biology. it's now about unnderstanding process, not simply categorizing.
I would be happy if this series continued forever. I've asked myself questions about this stuff for over a decade, unable to find answers, and now here they are, plain as day.
The universe was once a 8 sided octagonal crystalline ‘jelly’ with 10 vectors: 2 of which were 180 degrees, or opposite, of each other in opposite 90 degree planes; These opposite poles connected through the structure with one ‘like’ North and South Pole and eight ‘like’ Cardinal poles each representing a direction in 45 degree sections. This structure collapsed (or alternatively, imploded onto itself) at a single point at its midpoint between the North and South poles by first expanding into a round-ended cylindrical rigid octagonal crystalline structure, stabilizing: then through its diameter; collided, rebounded through itself, not quite becoming fully stable, rebounding again, becoming stable as a 𝚂𝚙𝚑𝚎𝚛𝚎 before exploding, projecting its ‘crystalline jelly’ matter infinitely into one barrel rolled sheet. Twas’ Beautiful those many years ago..
Surfing through PBS space time videos , watching different playlists multiple times ( I watched some videos more than 10 times at this point ) I truly feel like I'm taking an astrophysics course
First order phase transitions in the early universe is a very interesting topic, it doesn't have to be the inflaton field, and colliding bubbles might give rise to gravitational waves. Depending on the strength of the transition we might be able to observe these GW in future GW observatories. A very intriguing and interesting area of study. Maybe you should do a video about that...
Great video! I saw that Brian Greene PBS doc on the multiverse and it involved inflation, and while I got the vague idea I didn't get the "point" or what was so omg revolutionary...nor did I see why it had all these possible far ranging consequences but this video answered a lot of these! I get it, the doc was more basic level it gets your interest...wanna know more? Go to this guy lol
What if the 10 dimensional universe that broke in string theory and the six dimensional hyperspheres that curled up would take up volume in an existing three-dimensional universe pretty fast. Maybe then that snap left the 6d universe to "fall" out. Like going down a hill but outwards and everywhere... Great video!
Just thank you I always wanted to know more about this I have no words to explain how much I have learned Please make the next episode at the earliest possible
Dr. O'Dowd is awesome enough, especially since he looks 20 at almost 50. But I think his lectures assume you already have a working knowledge of astrophysical concepts. I still try to understand and enjoy it emensely.
Those bubbles reminded me of that doomsday scenario, where vacuum reverts to lower energy state and a bubble forms that destroys everything in it's wake.
Every single time I watch one of these videos my mind gets blown, I start having an existential crisis’ and become extremely philosophical questioning everything but not in a bad way. It makes my day to day ‘problems’ seem meaningless. When it all gets down to it in the end we are the universe experiencing it self and becoming self aware. That for me is the beauty of life and why we should cherish each day. Every single atom/particle all started at the same point on a journey that eventually lead to each life on this planet, each planet in a solar system, each solar system in a galaxy and each galaxy in the known universe... Truly the stuff of poetry.
@Sean G #NewPhysics137 trying to reconcile a singularity with an infinite source of momentum is just choosing to believe a different idea that still violates physics. Conscious thought isn’t energy. It’s information. And if anything life is not creating energy but recycling it. No energy is ever created. Potential energy is released or energy is converted.
Could the relationship between the field strength potential energy change as the Universe expands? If so, the local minimum could go away as the universe expands. This way all parts of the Universe would stop inflating at the same time.
So I'm imagining these bubbles like a pot of water starting to boil. The tiny little bubbles first form and float off rarely encountering another bubble. Yet as the pot continues to heat up the bubbles would continue to get bigger and collisions would occur more often. Yet this would happen in reverse if inflation caused the universe to cool. So first there were bigger bubbles then they brake down into smaller bubbles.
Is anybody else reminded of the holographic principle when Matt spoke of the inflaton dead zone bubbles? Or is my mind just reeling from all the Space Time weirdness of our universe? :-)
Given you are on the topic of inflation, afterwards may you please cover competing theories, such as CCC and it's hawking points? Great video as per usual!
God bless you for this Amazing series!!! Thank you so much!!! Would you please explain the experiments behind this topic? What astronomers are looking for to check these theories right now? Thank you!!! LOL from Italy! ♥️
I think that there will be an infinite number of most excellent SpaceTime videos because of cosmic inflation expanding the universe eternally and creating bubble universes; in fact, an infinite number of bubble universes.
A couple of questions: can the local minimum in the vacuum energy state give rise to favorable decay of few types of fundamental particles over others? And if so can that somehow explain the matter-antimatter asymmetry? My second question is, if the lowest vacuum energy bubbles coalesced, wouldn't that affect the CMB homogeneity? Big fan of the show.
@x_abyss I'm saying that the different cosmic limit might be what caused what we precive as the inflation. After all, time is a function of C. If C is lower, it means that everything in spacetime experiences time slower... EXCEPT spacetime. So it can easily expand a lot more before time speeds up again.
@Marik Zilberman I agree. Primordial stages of the universe could have had different cosmic limit. But the photons that eventually broke free of a much denser primordial universe are those which we perceive as cosmic microwave background radiation. Even if light traveled slowly back then, we can't know for certain. Look for earlier PBS Space Time videos about this.
This stuff takes some serious knowledge... I am gonna guess lots of calculus then physics and all that quantum QFT stuff he mentioned lol. Not to mention other knowledge about the universe. I hope to one day understand it all as an astrophysics major.
In a previous episode you mentioned that the [observable] universe does not contain enough mass to allow for the 'universe compacted to an infinitesimally small singularity' cyclic big bounce model, however given that no properties for anything existed at t=0, is it possible (even more probable) that fundamental force properties were different? If the universal 'constants' pre big bounce are not the same as post big bounce, can we truely rule out inflation hypothesis?
If the inflaton field energy graph illustrates the profile of a single particle (I assume that's the case as it quantum tunneled) would this effect not be lost when scaled up just as quantum effects are mostly not visible at our scale?
I wish my mind would be able to expand in the same way by following PBS Space Time eternally. Well, maybe I am a (part of a) Boltzmann Brain and this is actually happening like that.
The Higgs field has a non-zero energy value everywhere and its responsible for giving particles an intrinsic mass, that much makes sense, but could this somehow be related to dark energy or the inflaton? Just an idea I had, not entirely sure how it would fit
reacting to all video's: considering all your best models combined, what are the MOST fundamental principles that define and describe our reality/cosmos in your opinion? thanks!
Thanks for the video, awesome as always. I just only have issue with the background music/tone theme which I find it distracting (and a bit annoying) specially when I listen to the clip in a quiet zone.
wzrubicon 1 I feel like you might be conflating theory and fact a bit (at least with how the terms are used in the scientific realm) because scientific theories are probably better described as frameworks of relations and interactions between very real individual observations (aka what I would say is more commonly understood as a "facts"). In other words, you can _only_ really have theories about such interactions considering there is no way to perceive an "objective" worldview of such causal relationships, only increasingly more consistent and explanatory models based on new observations and alternate hypothesis.
Thanks for enlightening me that in quantum field theory, an elementary particle is an oscillation in a local field. This being so, what is the difference between QFT and string theory?
Soo...this video gave me a much better idea of the whole vacuum decay thing. And also explains why another vacuum decay is still possible - dark energy is still, in some form, a higher vacuum energy than it otherwise could be, and so yet another decay is possible. I know you guys did a video on just this, but this video in particular gave me a much better understanding of why that is possible and what it would mean, what it would do, etc.
Wow, I watched the quantum tunnel 'birthing' of uncountable universes in the inflaton field after taking 900mg of mescaline, had not realized this theory was behind it until now.
According to the hypothesis of the evolution of the universe, when it has not yet evolved, all matter and energy are in balance, and the matter and energy it needs are diffused outward in accordance with the laws of physics (the gravitational force of matter balance is canceled), so where is the matter, energy and gravitational to evolve? So it can only be created by God.
reacting to earlier video's: how does information travel/interact within the wave-function 'before' collapse? does anything like causality, or relativity, or a maximum speed apply? cheers!
when i render an image on my computer with my 3D-modeler, that rendering goes in a few passes,. why could the cosmos not 'render' reality in a similar way _ in passes? A VIRTUAL PASS AND A REAL PASS. if so, how could we describe the virtual interactions/mechanisms? does it simply work at significantly higher speeds? so that us real-worlders think virtual dealings happen instantly? just thinking out loud here :) happy day
@Drkwll there is STRUCTURE within the 'virtual' wave-function. i'm questioning how the parts of that virtual structure communicate with each other. or does this structure just 'emerge in some virtual realm' as a whole, WITHOUT and time-ish or space-ish internal interaction. (deliberately not using the words timelike and spacelike) could the virtual 'world' within a quantum state have a number of similar principles and mechanisms as the real world? in the case of the double slit experiment: how does the virtual interference pattern IN the wave-function arise, that guides/calculates/distributes the path/probabilities of the actually observed real photons that hit the screen in a real pattern of bands? ( In the real world, structure can only exist when there is an expanse of time and space. if there was no speed limit for instance, in the real world, all info could be everywhere instantly and there was no structure. ) another example: when the entanglement of 2 particles collapses as the result of one of them being observed, the other particle matches it's observed properties instantly right? so there appears to be a 'magical' form of virtual communication within the quantum state. in the pilot-wave interpretation there is a whole virtual realm of interacting 'stuff' that appears to follow rules and principles similar to the real world.
in the pilot-wave interpretation there could perhaps be such phenomena? ... i find it difficult to imagine any real or virtual 'structure' in space-time where all information exists/interacts at the same 'single moment', how can 'virtual' waves/paths within the wave-function-shizzle boost each-other or cancel each-other out, if they cannot interact with each other in any time-ish way? ... speculation wildly: this virtual time could be perpendicular to real time or simply tick a hell of a lot slower, giving a higher virtual-C than the real C. Then again maybe i'm really/virtually crazy :)
You mentioned that the universe could go through expansion and contraction which got me thinking what happens if contraction takes over inflation, could the universe implode? Which led me to wikipedia looking at the big bounce. Do you have any videos that might touch on this more?
Tiny creatures Living on a tiny rock flying through space Being able to see only a small portion of the universe And yet we are able to see what is there thousands of light years away, create accurate models and understand how the entire universe formed This is the true power of *T H I N C C*
@Slate of Fate I don't destroy. I think that most people don't. To cast blame on all of us is a way of excusing the behavior of the few who behave badly.
I try to make sure I'm getting the key points of each episode, even if I don't grasp all the details. Here is what I got out of this one: The early universe experienced inflation for reasons very similar to the current expansion of the universe, i.e. dark energy. This is a sort of ambient energy in a quantum field, than which the field can go no lower. In the case of inflation, the "Inflaton" field was in a false-vacuum state, where it had surprisingly high energy, and was causing a rapid dark-energy-like expansion. However, the field managed to escape this trough, and has since dropped to its true vacuum state, ending its reign of terror as the big daddy of spatial expansion. Does that sound about right?
This is how everything ought to be taught in US schools. This whole channel is like this, allowing for some assumptions of prior knowledge that are pretty understandable given the subject matter. No "skip to the current conclusion, this is how it is and that's what I want you to put on the test along with the names of these people who actually got to feel like they learned things", just an enjoyable buildup of concepts, and historical background into significant points in reaching our current understanding of the universe. And I know, there are often problems that run even deeper than the subject matter in public primary/secondary schools that contribute to the unfortunately degraded form of education, like funding. We really should take education more seriously, and try to elect like-minded people on the subject, because uninspiring education isn't good education for a lot of people.
I realize that it is a "fringe theory" but VSL (variable speed of light) can also explain cosmic inflation in a relatively easy fashion. Of course I have no idea how to explain why the speed of light settled to its current "constant" rate but I think you have to admit that VSL does make for a seemingly straight-forward explanation.
According to the hypothesis of the evolution of the universe, when it has not yet evolved, all matter and energy are in balance, and the matter and energy it needs are diffused outward in accordance with the laws of physics (the gravitational force of matter balance is canceled), so where is the matter, energy and gravitational to evolve? So it can only be created by God.
I've never heard a more... explanatory... explanation of the big bang and inflation. Suddenly I feel like I kinda get it. A lot more than I did before.
Could you explain the challenges faced by VSL alternatives to inflation, for example like J.W. Moffat's? I assume there is good reason it isn't taken seriously but it seems awfully strange to me to posit the existence of some additional "inflaton" field ad hoc (where exactly does the inflaton fit in the standard model?) rather than see if we can model the appearance of inflation using fields we know exist.
I am stoked, nice field animation! Oh, a new particle, even, we have evidence that it's there and affecting our age of the universe measurements! Maybe it's already in the collider results, lol. Don't you guys figure out the energy or frequency and then look for it at the colliders? Imagine, Webb sees it, it was just a little too cold, lol. Or maybe Webb isn't cold enough! Or maybe the wrinkles are so small we need two or 3 Webbs to see it!
LGX That's very likely because you are just missing some basics. Just watch an episode and when you come to a point where you don't understand something, google it until you understand it, then continue and so on. Do this for enough episodes and you'll at some time have pimped your general understanding of basic physics to such a point were all of this makes perfect sense and you understand it.
Ix Suomi A "theory" in science doesn't have the same definition as we use it in daily life. A theory is a well stablished hypothesis, with a mathematics background. For example the "relativity theory" is not just some explanations about the world without a prove. You should not mistake "theory" with "hypothesis".
I always assumed the inflation was at least in part caused by the internal pressure of the sea of highly energetic particles it contained and as these cooled as spacetime expanded basically with more space less collisions happened causing less energy transfer and slowing the inflation of the universe.
Anyone else absolutely love the animation of the inflaton field? I could do acid and watch it on repeat all day xD (never had the luxury of trying acid btw XDD)
According to the hypothesis of the evolution of the universe, when it has not yet evolved, all matter and energy are in balance, and the matter and energy it needs are diffused outward in accordance with the laws of physics (the gravitational force of matter balance is canceled), so where is the matter, energy and gravitational to evolve? So it can only be created by God.
Matt O'Dowd is such a great writer AND presenter. You can tell he really cares about the science and delivers his knowledge very elegantly
@Dale Bewan Great points and summary! Thanks! 💕🙏
The precise mathematical interpretation of the Cosmic Microwave Background proves conclusively that the Universe had no beginning has no limit in size and will not end.
Where did Gabe Powers go...??? 😆 🤣 😂
when i boot my computer, the RAM sees almost instant inflation of data
I teach a high school astrophysics class and I rely heavily on this series to boost my understanding and help me translate difficult concepts to my students. I’m a much better - and more educated - teacher. Thank you Matt O’Dowd.
@Nigel Kirk that'd be perfect. Good idea
@Joe Mackenzie Should we just ban science in school then? Because the first rule of science - especially quantum physics and astrophysics is "If you think you understand it, you clearly don't."
@Tyler Boothman I agree; however, you shouldn't be teaching something if you rely "heavily" on anything else to boost your own understanding of it. It's like having a translator that doesn't really know the language they're translating..
@Joe Mackenzie Understanding something is not a binary state.
"to help boost my understanding"
Use your reading comprehension.
you teach things to kids that you dont yourself understand? So you just regurgitate pbs spacetime to your students; without the understanding necessary to do so...kewwl
I would be lying if I said I understood what this guy is saying, and yet I continue to watch these videos.
I feel like that’s the fun of it
Out of all the science channels I understand nothing about, this is my favorite.
@Victor McClellan welcome to science lmao
Its a weird learning curve, after watching all of his videos i have got to say, what little i have come to understand has just made me waaay more confused about the nature of reality than i was at the beginning. Every question answered is 10 new questions asked.
I understood a bit and can confidently say that it had nothing to do with the video title.
For everyone who's confused: I've been watching these videos diligently for years and they do a great job of scaffolding to get you to the point where you can actually understand this level of cosmology. Go back and rewatch each one as many times as you need, you'll get there!
It helps to watch with a friend and try to explain what you understood from each video in your own words.
LOVE to the SPACETIME crew! Thanks for making physics accessible to the rest of us!
I love how both Fermilab and Space time are using phase transitions of water to describe cosmology or neutrino physics concepts. It makes the material really easy to grasp.
Literally how it’s described to undergrads
I do hope that that "another time" for magnetic monopoles isn't too far into the future. I'm quite fascinated by the concept, but just can't wrap my mind around envisioning them. They're just _so_ foreign. I'd love to hear your explanation and walk-through of them.
Man, do I love your cosmology episodes. BEST physics channel on KZclip.
agree
I was gonna make the exact same comment then i saw yours with 800 likes :)
@Pedro Costa Seeker is clickbait news channel compared to space time
Try the thunderbolts project
Isaac Arthur
Absolutely fantastic visualizations of quantum fields! It really helped me develop an intuitive sense for what was happening.
Incredible episode. I feel I grasp this idea far far better than I ever have before. Many thanks for the continued excellent standard of content.
What a legend, Alan Guth, his concept of the inflaton field is definitely onto something bigger. I got a serene feeling as he explained the re-thermalisation of the early universe. It makes so much sense, the decay of virtual inflaton particles to actual particle converting the potential energy to tangible forms and possibly leading to phase transforms in the inflaton field. Yes I have already watched the sequel video, but the fact that phase transforms can occur in the potential energy of field strengths is so cool, especially when everything heats up again ;) I guess the physical constants in nature would have been absolutely scewed at that initial point of the high energy inflaton field
This is an awesome episode! It helped me understand the nature of the Higgs field as well. Great job!
For me, one of Guth's biggest contributions was his lay book ( _The Inflationary Universe_ ) explaining inflation and how he developed it.
Well done. You are becoming an expert in interpreting these concepts without the math and scientific lingo. Thanks and to all the staff who support you.
@Eric Graham Don't confuse "math" with "calculations".
@Firebrand Give me a break, these are some of the best science related videos on youtube- and I would argue that Space Time drills down on its topics a lot further than many other documentaries. They always give you the feel of the math when its reasonable, and are quite good about using terminology. What would be the point of showing math that no one would understand? There were calculations I had to do in my physics courses that would take up multiple sheets of paper, its not really reasonable or feasible to expect them to show all the math involved with a lot of these concepts- it wouldn't do anything but distract and confuse. It's also totally feasible to understand at a practical level, many of these ideas in physics. That's like saying you need to know how to code in programming languages to be able to understand how to use a computer- sure, it gives you a lower level deeper understanding that could enrich your understanding of what is happening , but its not required. I have to be honest, math was always my least favorite part of physics and astronomy.
Firebrand for kindergarteners and preteens? That’s quite a hyperbole.
Problem is there's no way to really understand this stuff without the math. You're just being fooled into thinking you know more than you do.
No offense of course.
@Justin The only reason this channel is better than the myriad of "DUDE WEED LMAO SPACE" tier channels or shows out there is exactly because (at least in some of the older videos I've watched) they actually show some of the basic math behind it (even if it's just a graph of a function), because it's absolutely necessary to understand anything at all beyond learning a bunch of terminology, something which a lot of people misintepret as having learned anything. There is absolutely no way around it if you want to actually understand some of it, even on a surface level. And no I am not a physicist.
Thanks a lot for all of ur effort..all content shown are exceptional and highly motivational. Proud to be learning physics
Thank you for explaining how inflation implies a multiverse. I've heard Alan Guth and others mention this numerous times but never took the time to explain why. This is the first time I can take the notion of the multiverse seriously.
Once more a commendable presentation of a conceptually complex topic. Digesting obtuse specialist journal publications, then distilling them into talking points non-specialist might appreciate, then crafting those into a script and visuals able to communicate the obtuse; that is a commendable and rare accomplishment. Cheers!
These videos are amazing and you and your team are amazing. I admit I often needs to see them several times, but the universe has all my life been a corner stone. Arthur C Clark was my favourite science fiction writer. And I was lucky to live where it was without lights. Very north in Denmark. So my imagination was able to evolve. But as you I was very lucky to also be quite good to music, so my education was the classic and now (15 years ago) I really took my time to get the universe seriously back in my life. And you tube are a gold mine at knowledge and I use every available moment to catch up. So music and science do keep my young, unfortunately I do miss to have some to ping pongs theses complicated issues with. But I I’m happy to learn what new and fantastic things, and I’m so impressed how far we have been able to go, only in so short time. The only thing I’m worried about, how to reach quantum gravity or the theory of everything ( GUT) the math seems to be able to provide a solution,but how on earth can we measure, test or will we need to settle until we are able to measure multiverse etc. And another thing the missing mass and the acceleration of the universe. What an exciting time. I surely hope I will live long enough to see some solutions .
Hey guys. Just discovered your channel this is really awesome, thank you!! I have a question:
I read about our own supermassive black hole increasing its radiation in the last months, how are we measuring this over such distance?
I was thinking about what the universe was like before the Big Bang.
Nothing came to mind.
@CoD:M Tank you need help, don't worry I got a good doctor for you.
Thanks for the crisp and very informative episode!! I was just about to finish the book written by Alan Guth’s The Inflationary Universe and your episode served as a summarization of it!!
I love having my mind blown by Space Time. Just brilliant content, every time.
Love this channel!
Can you do an episode about Saturn's rings please?
An idea for possible future episodes: It would be cool to learn about some historical theories that have been debunked or abandoned, and why. For example,
Tachyon particles
Aether theories
Various Planet X theories, etc.
I always hit the "like" button first before watching your videos because I know I'm going to love it. Thanks for the best technical lectures ever!
Thanks Matt. Another great episode! This channel has changed my life.
Fantastic. Easily some of my favorite media of any kind. Thanks for making it great; it's obvious that a lot of effort goes into every video.
9:30 Or a minor perturbation (flick the bottle with your finger). This perturbation causes a wave of higher density to traverse the supercooled water with a region behind the wave being even colder. This can cause a small ice crystal to form, which then slowly moves across the container freezing the rest of the water.
I'm still unsure how we talk about "time" in the early universe and I often feel like this gets brushed aside in these kinds of descriptions. We say that certain things happened at certain points in time, but since time is inextricably linked to space, then surely the "amount of time" that the universe experienced inflation can't be so trivially described? Doesn't the expansion of space itself influence the description of time in that space? If so, then perhaps it's relatively inconsequential under Hubble expansion, but surely under inflation the effect must be noticeable. Or am I thinking about this all wrong?
@Frank Schneider We are part of spacetime. Are we expanding?
That's a great question Dale.
@Frank Schneider the participation of physicists in biology has revolutionized biology. it's now about unnderstanding process, not simply categorizing.
@Sean G #NewPhysics137 lol
Love the enthusiasm he has for science!
Excellent intro to intrinsics of inflation. Would love to see this channel slowly going into the mathematical details of the theories.
I would be happy if this series continued forever. I've asked myself questions about this stuff for over a decade, unable to find answers, and now here they are, plain as day.
Sucks that we will never know all the answers though. But, then again, would the Cosmos be as profound if we had all the answers? I think not.
Truly great job
Everytime I think I have a decent understanding of cosmology you guys release an episode that gives me a hundred more questions
Which is exactly how science works. Answering a question usually results in a dozen or more new questions.
Clearly a metaphorical reference - but could we have a frame of comparison?
The universe was once a 8 sided octagonal crystalline ‘jelly’ with 10 vectors: 2 of which were 180 degrees, or opposite, of each other in opposite 90 degree planes; These opposite poles connected through the structure with one ‘like’ North and South Pole and eight ‘like’ Cardinal poles each representing a direction in 45 degree sections. This structure collapsed (or alternatively, imploded onto itself) at a single point at its midpoint between the North and South poles by first expanding into a round-ended cylindrical rigid octagonal crystalline structure, stabilizing: then through its diameter; collided, rebounded through itself, not quite becoming fully stable, rebounding again, becoming stable as a 𝚂𝚙𝚑𝚎𝚛𝚎 before exploding, projecting its ‘crystalline jelly’ matter infinitely into one barrel rolled sheet.
Twas’ Beautiful those many years ago..
@Woffenhorst satisfaction is the cure
Surfing through PBS space time videos , watching different playlists multiple times ( I watched some videos more than 10 times at this point ) I truly feel like I'm taking an astrophysics course
First order phase transitions in the early universe is a very interesting topic, it doesn't have to be the inflaton field, and colliding bubbles might give rise to gravitational waves. Depending on the strength of the transition we might be able to observe these GW in future GW observatories.
A very intriguing and interesting area of study. Maybe you should do a video about that...
Este es el mejor vídeo que he visto en toda mi vida. Gracias por tan valioso aporte.
Great video! I saw that Brian Greene PBS doc on the multiverse and it involved inflation, and while I got the vague idea I didn't get the "point" or what was so omg revolutionary...nor did I see why it had all these possible far ranging consequences but this video answered a lot of these! I get it, the doc was more basic level it gets your interest...wanna know more? Go to this guy lol
What if the 10 dimensional universe that broke in string theory and the six dimensional hyperspheres that curled up would take up volume in an existing three-dimensional universe pretty fast. Maybe then that snap left the 6d universe to "fall" out. Like going down a hill but outwards and everywhere... Great video!
Fascinating episode!!! Thanks to everyone at PBS-Spacetime for continuing to put together this fantastic content.
Just thank you
I always wanted to know more about this
I have no words to explain how much I have learned
Please make the next episode at the earliest possible
I love both Matt O' Dowd and Physics.
Slowly and slowly, little by very little, I start to really understand these things.
Dr. O'Dowd is awesome enough, especially since he looks 20 at almost 50. But I think his lectures assume you already have a working knowledge of astrophysical concepts. I still try to understand and enjoy it emensely.
Those bubbles reminded me of that doomsday scenario, where vacuum reverts to lower energy state and a bubble forms that destroys everything in it's wake.
Every single time I watch one of these videos my mind gets blown, I start having an existential crisis’ and become extremely philosophical questioning everything but not in a bad way. It makes my day to day ‘problems’ seem meaningless. When it all gets down to it in the end we are the universe experiencing it self and becoming self aware. That for me is the beauty of life and why we should cherish each day. Every single atom/particle all started at the same point on a journey that eventually lead to each life on this planet, each planet in a solar system, each solar system in a galaxy and each galaxy in the known universe... Truly the stuff of poetry.
Beautifully put. Your words made my day better.
I'd suggest you see your local Zen master...
10:04 That "Inflaton Field" Illustration just explains so many concepts of Cosmology & QFT! Mind-blowing stuff!
Thought provoking. The most interesting thing on the internet. Thank you!
Has the hypothetical Vacuum Decay catastrophe ever been discussed in any space time videos?
Could you explain the recent disputes about the Hubble Constant, and how that affects the expansion of the universe?
This was a fantastic explanation 👍🏻👍🏻
“This story seems like a bit of a STRETCH”. Nicely done.
@Sean G #NewPhysics137 trying to reconcile a singularity with an infinite source of momentum is just choosing to believe a different idea that still violates physics. Conscious thought isn’t energy. It’s information. And if anything life is not creating energy but recycling it. No energy is ever created. Potential energy is released or energy is converted.
“You really gave my hole a STRETCH!”
Could the relationship between the field strength potential energy change as the Universe expands? If so, the local minimum could go away as the universe expands. This way all parts of the Universe would stop inflating at the same time.
So I'm imagining these bubbles like a pot of water starting to boil. The tiny little bubbles first form and float off rarely encountering another bubble. Yet as the pot continues to heat up the bubbles would continue to get bigger and collisions would occur more often. Yet this would happen in reverse if inflation caused the universe to cool. So first there were bigger bubbles then they brake down into smaller bubbles.
Is anybody else reminded of the holographic principle when Matt spoke of the inflaton dead zone bubbles? Or is my mind just reeling from all the Space Time weirdness of our universe? :-)
Love the mind blowing info. Thank you!
Awesome video, well put together!
Given you are on the topic of inflation, afterwards may you please cover competing theories, such as CCC and it's hawking points? Great video as per usual!
God bless you for this Amazing series!!! Thank you so much!!! Would you please explain the experiments behind this topic? What astronomers are looking for to check these theories right now? Thank you!!! LOL from Italy! ♥️
I think that there will be an infinite number of most excellent SpaceTime videos because of cosmic inflation expanding the universe eternally and creating bubble universes; in fact, an infinite number of bubble universes.
Thank you for this explanation. I finally grasp the phase transition aspect of inflation models..
Incredible episode Matt!!
Great explanation and animation!
A couple of questions: can the local minimum in the vacuum energy state give rise to favorable decay of few types of fundamental particles over others? And if so can that somehow explain the matter-antimatter asymmetry? My second question is, if the lowest vacuum energy bubbles coalesced, wouldn't that affect the CMB homogeneity? Big fan of the show.
@Dean Fuqua?
@Marik Zilberman Absence of evidence is not evidence of absence.
@x_abyss I'm saying that the different cosmic limit might be what caused what we precive as the inflation. After all, time is a function of C. If C is lower, it means that everything in spacetime experiences time slower... EXCEPT spacetime. So it can easily expand a lot more before time speeds up again.
@Marik Zilberman I agree. Primordial stages of the universe could have had different cosmic limit. But the photons that eventually broke free of a much denser primordial universe are those which we perceive as cosmic microwave background radiation. Even if light traveled slowly back then, we can't know for certain. Look for earlier PBS Space Time videos about this.
@x_abyss the primordial universe seems like a prime candidate for breaking the laws of physics as we know them.
This stuff takes some serious knowledge... I am gonna guess lots of calculus then physics and all that quantum QFT stuff he mentioned lol. Not to mention other knowledge about the universe. I hope to one day understand it all as an astrophysics major.
Another remarkably beautiful explanation!
In a previous episode you mentioned that the [observable] universe does not contain enough mass to allow for the 'universe compacted to an infinitesimally small singularity' cyclic big bounce model, however given that no properties for anything existed at t=0, is it possible (even more probable) that fundamental force properties were different? If the universal 'constants' pre big bounce are not the same as post big bounce, can we truely rule out inflation hypothesis?
Wow, brave and mind blowing theory, absolutely brilliant, thank you.
If the inflaton field energy graph illustrates the profile of a single particle (I assume that's the case as it quantum tunneled) would this effect not be lost when scaled up just as quantum effects are mostly not visible at our scale?
Hope you guys eventually cover the eternal inflation theory. Love this stuff.
Anything with the word "eternal" in it is worth covering.
Booga300 lmao, I do the same sometimes. Then I just end up deleting my comment 😂
Haha, I guess I should watch till the end before commenting.
I wish my mind would be able to expand in the same way by following PBS Space Time eternally.
Well, maybe I am a (part of a) Boltzmann Brain and this is actually happening like that.
The Higgs field has a non-zero energy value everywhere and its responsible for giving particles an intrinsic mass, that much makes sense, but could this somehow be related to dark energy or the inflaton? Just an idea I had, not entirely sure how it would fit
Man, I absolutely love the animations
reacting to all video's: considering all your best models combined, what are the MOST fundamental principles that define and describe our reality/cosmos in your opinion? thanks!
Lie groups and symmetries. Noether's theorem.
Thanks for the video, awesome as always. I just only have issue with the background music/tone theme which I find it distracting (and a bit annoying) specially when I listen to the clip in a quiet zone.
Really enjoy these topics, the early universe is such an interesting topic
wzrubicon 1 I feel like you might be conflating theory and fact a bit (at least with how the terms are used in the scientific realm) because scientific theories are probably better described as frameworks of relations and interactions between very real individual observations (aka what I would say is more commonly understood as a "facts"). In other words, you can _only_ really have theories about such interactions considering there is no way to perceive an "objective" worldview of such causal relationships, only increasingly more consistent and explanatory models based on new observations and alternate hypothesis.
wow i did not catch any of that 😑
Thanks for enlightening me that in quantum field theory, an elementary particle is an oscillation in a local field. This being so, what is the difference between QFT and string theory?
Soo...this video gave me a much better idea of the whole vacuum decay thing. And also explains why another vacuum decay is still possible - dark energy is still, in some form, a higher vacuum energy than it otherwise could be, and so yet another decay is possible. I know you guys did a video on just this, but this video in particular gave me a much better understanding of why that is possible and what it would mean, what it would do, etc.
I would love to be able to fully understand all these hypotheses
Wow, I watched the quantum tunnel 'birthing' of uncountable universes in the inflaton field after taking 900mg of mescaline, had not realized this theory was behind it until now.
One wonders if we'll ever have a good enough understanding to extrapolate what the characteristics of inflaton particles would have been.
Background ambient music is a bit intrusive, but I'm supremely happy to see this episode made!
Quantum physics is so fascinating it's enticing me to get into and learn calculus.
@Ditch Weed Science cannot prove which is a god, but religion must conform to science to be,not scientific hypothesis
@ahahahha Aisyah brahman
According to the hypothesis of the evolution of the universe, when it has not yet evolved, all matter and energy are in balance, and the matter and energy it needs are diffused outward in accordance with the laws of physics (the gravitational force of matter balance is canceled), so where is the matter, energy and gravitational to evolve? So it can only be created by God.
Amazing. Can't wait for the future episodes.
reacting to earlier video's: how does information travel/interact within the wave-function 'before' collapse? does anything like causality, or relativity, or a maximum speed apply? cheers!
when i render an image on my computer with my 3D-modeler, that rendering goes in a few passes,.
why could the cosmos not 'render' reality in a similar way _ in passes?
A VIRTUAL PASS AND A REAL PASS. if so, how could we describe the virtual interactions/mechanisms?
does it simply work at significantly higher speeds?
so that us real-worlders think virtual dealings happen instantly?
just thinking out loud here :)
happy day
@Drkwll there is STRUCTURE within the 'virtual' wave-function.
i'm questioning how the parts of that virtual structure communicate with each other.
or does this structure just 'emerge in some virtual realm' as a whole,
WITHOUT and time-ish or space-ish internal interaction. (deliberately not using the words timelike and spacelike)
could the virtual 'world' within a quantum state have a number of similar principles and mechanisms as the real world?
in the case of the double slit experiment: how does the virtual interference pattern IN the wave-function arise,
that guides/calculates/distributes the path/probabilities of the actually observed real photons that hit the screen in a real pattern of bands?
( In the real world, structure can only exist when there is an expanse of time and space.
if there was no speed limit for instance, in the real world, all info could be everywhere instantly and there was no structure. )
another example:
when the entanglement of 2 particles collapses as the result of one of them being observed,
the other particle matches it's observed properties instantly right?
so there appears to be a 'magical' form of virtual communication within the quantum state.
in the pilot-wave interpretation there is a whole virtual realm of interacting 'stuff'
that appears to follow rules and principles similar to the real world.
@rjw elsinga that was confusing.
in the pilot-wave interpretation there could perhaps be such phenomena? ... i find it difficult to imagine any real or virtual 'structure' in space-time where all information exists/interacts at the same 'single moment', how can 'virtual' waves/paths within the wave-function-shizzle boost each-other or cancel each-other out, if they cannot interact with each other in any time-ish way? ... speculation wildly: this virtual time could be perpendicular to real time or simply tick a hell of a lot slower, giving a higher virtual-C than the real C. Then again maybe i'm really/virtually crazy :)
Sometimes I get lost but I keep watching because it's really interesting. I'm an idiot but I love science.
You mentioned that the universe could go through expansion and contraction which got me thinking what happens if contraction takes over inflation, could the universe implode? Which led me to wikipedia looking at the big bounce. Do you have any videos that might touch on this more?
I found what i was looking for in your "Did Time Start at the Big Bang?" video. Great videos thank you for all that you do!
Tiny creatures
Living on a tiny rock flying through space
Being able to see only a small portion of the universe
And yet we are able to see what is there thousands of light years away, create accurate models and understand how the entire universe formed
This is the true power of
*T H I N C C*
*THINCCC AF*
@Jesse Lee But...we can only see the things that emit light...kinda makes you wonder what else is out there that doesnt emit light....
Not to argue, but we don't understand.
We're still guessing (hence the repeated term "hypothetical").
@Slate of Fate I don't destroy. I think that most people don't. To cast blame on all of us is a way of excusing the behavior of the few who behave badly.
@Einstein Alberto r/unexpectedoffice
Ive always thought of the Big Bang as the moment they turned on the computer that generated this simulation we live in.
I try to make sure I'm getting the key points of each episode, even if I don't grasp all the details. Here is what I got out of this one:
The early universe experienced inflation for reasons very similar to the current expansion of the universe, i.e. dark energy. This is a sort of ambient energy in a quantum field, than which the field can go no lower. In the case of inflation, the "Inflaton" field was in a false-vacuum state, where it had surprisingly high energy, and was causing a rapid dark-energy-like expansion. However, the field managed to escape this trough, and has since dropped to its true vacuum state, ending its reign of terror as the big daddy of spatial expansion.
Does that sound about right?
Channel keeps getting better and better. Best on KZclip.
This is how everything ought to be taught in US schools. This whole channel is like this, allowing for some assumptions of prior knowledge that are pretty understandable given the subject matter. No "skip to the current conclusion, this is how it is and that's what I want you to put on the test along with the names of these people who actually got to feel like they learned things", just an enjoyable buildup of concepts, and historical background into significant points in reaching our current understanding of the universe.
And I know, there are often problems that run even deeper than the subject matter in public primary/secondary schools that contribute to the unfortunately degraded form of education, like funding. We really should take education more seriously, and try to elect like-minded people on the subject, because uninspiring education isn't good education for a lot of people.
I realize that it is a "fringe theory" but VSL (variable speed of light) can also explain cosmic inflation in a relatively easy fashion. Of course I have no idea how to explain why the speed of light settled to its current "constant" rate but I think you have to admit that VSL does make for a seemingly straight-forward explanation.
According to the hypothesis of the evolution of the universe, when it has not yet evolved, all matter and energy are in balance, and the matter and energy it needs are diffused outward in accordance with the laws of physics (the gravitational force of matter balance is canceled), so where is the matter, energy and gravitational to evolve? So it can only be created by God.
I've never heard a more... explanatory... explanation of the big bang and inflation. Suddenly I feel like I kinda get it. A lot more than I did before.
Could you explain the challenges faced by VSL alternatives to inflation, for example like J.W. Moffat's? I assume there is good reason it isn't taken seriously but it seems awfully strange to me to posit the existence of some additional "inflaton" field ad hoc (where exactly does the inflaton fit in the standard model?) rather than see if we can model the appearance of inflation using fields we know exist.
This is probably my new favorite channel. Really well put
Could you or have you done a video on the possibility that the universe is larger than what we can observe
So at the moment of the big bang, it expanded at massive super-luminal speeds and then when it settled, the speed of light became a hard velocity?
I am stoked, nice field animation! Oh, a new particle, even, we have evidence that it's there and affecting our age of the universe measurements! Maybe it's already in the collider results, lol. Don't you guys figure out the energy or frequency and then look for it at the colliders? Imagine, Webb sees it, it was just a little too cold, lol. Or maybe Webb isn't cold enough! Or maybe the wrinkles are so small we need two or 3 Webbs to see it!
This channel is so damn interesting but nearly every video goes over my head.
LGX
That's very likely because you are just missing some basics. Just watch an episode and when you come to a point where you don't understand something, google it until you understand it, then continue and so on. Do this for enough episodes and you'll at some time have pimped your general understanding of basic physics to such a point were all of this makes perfect sense and you understand it.
Play it at half speed. Give your brain a bigger chance to keep up.
Its science fiction. Enjoy the ride.
Ix Suomi A "theory" in science doesn't have the same definition as we use it in daily life. A theory is a well stablished hypothesis, with a mathematics background. For example the "relativity theory" is not just some explanations about the world without a prove. You should not mistake "theory" with "hypothesis".
Ix Suomi these do NOT look like college kids
I always assumed the inflation was at least in part caused by the internal pressure of the sea of highly energetic particles it contained and as these cooled as spacetime expanded basically with more space less collisions happened causing less energy transfer and slowing the inflation of the universe.
Out of all the science channels I understand nothing about, this is my favorite.
Anyone else absolutely love the animation of the inflaton field? I could do acid and watch it on repeat all day xD (never had the luxury of trying acid btw XDD)
According to the hypothesis of the evolution of the universe, when it has not yet evolved, all matter and energy are in balance, and the matter and energy it needs are diffused outward in accordance with the laws of physics (the gravitational force of matter balance is canceled), so where is the matter, energy and gravitational to evolve? So it can only be created by God.