The Big Bang Theory | Roger Penrose, Sabine Hossenfelder, Sean Carroll, Chris Impey and more

Roger Penrose, Sabine Hossenfelder, Sean Carroll, David Tong, Laura Mersini-Houghton, Chris Impey and Bjørn Ekeberg debate the Big Bang Theory.
#SabineHossenfedler #RogerPenrose #BigBangTheory
Debates and talks in order of appearance:
David Tong - Wonders of the Big Bang (2013)
iai.tv/video/wonders-of-the-b...
Sean Carroll, Laura Mersini-Houghton and Roger Penrose - Big Bang creation myths (2018)
iai.tv/video/big-bang-creatio...
Sabine Hossenfelder, Bjørn Ekeberg and Christopher Impey - Our story of the universe (2020)
iai.tv/video/our-story-of-the...
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Picture credits
"Professor Sir Roger Penrose", Biswarup Ganguly, Wikimedia. Edited. Licensed by CC BY 3.0: creativecommons.org/licenses/...
"Chris Impey" W.W. Norton and Co., National Public Radio. Edited Licensed by CC BY-SA 4.0: creativecommons.org/licenses/...

[@TheInstituteOfArtAndIdeas]

To watch more debates from the world's leading thinkers, visit iai.tv/player

[@reasonerenlightened2456]

The audacity to suggest that this amount of insane energy can spring out into existence from nothing is borderline stupidity. Effectively it is a version of the Boltzmann brain theory i.e. there was nothing and suddenly there was an insane amount of energy. It is absolutely clear that BB is a result of processes we know nothing about ... the whole BB could be just a jet of energy similar to the jets coming out of black holes.

[@jeffreywilliams5093]

Where did these science talks take place? When? I ask, because the concept of place-time is important to me.

[@JR-vm4tm]

Can Penrose get another lifetime to stay with us and produce more great work for humanity, we love you Penrose.

[@FreshhGraffz]

just wish that was an actual debate and not just random videos cut together...

[@TheEmergingPattern]

Yes, when was it recorded?

[@michaeldamolsen]

Not sure it is polite to refer to another channel, but I'll do it anyway. Over on World Science Festival they feature some great debates going back several years. That said, if you look closer at iai (this channel), they have other talks by scientists that do not necessarily agree with each other. You could consider that a longer form of debate too.

[@amandawaller3479]

The entire debates are posted on the IAI"s website behind a paywall.

[@markuswx1322]

Penrose, probably the most brilliant person there, was put last and shushed. Shameful.

[@michaeldamolsen]

@@markuswx1322 No matter how much Penrose I see, it never seems to be enough. I can highly recommend his books as well, they are extraordinarily well written.

[@jantestowy123]

Penrose explains infinity a guy chimes in with "one minute". There is nothing funnier than that.

[@phaecops]

Yes. Utterly appalling.

[@NondescriptMammal]

Funny but also sad. I would have like to hear Penrose finish his thoughts unhurried.

[@jackdeath]

_One Minute to Infinity_ sounds like the title of a _Red Dwarf_ book.

[@NidusFormicarum]

He went on for eons.

[@onehitpick9758]

What kind of a universe do we live in when you tell someone like Penrose "one minute"? Every word he says is to be treasured. Everybody else was just saying the same old stuff about the big bang we've heard over a million times. Give Penrose some time, next time.

[@38vocan]

I kinda agree

[@joaidane]

should have added: "to talk about time!"

[@alex79suited]

They don't like to give anybody time that knows the big bang theory is incorrect. Penrose is on the right track I believe.

[@gorgonopsian5611]

The best part of the whole conversation was when Rodger Penrose spoke and it seemed like he was being rushed to finish his talk. How dare they!

[@bidyutbikashhazarika481]

This video is a testament to the unassuming brilliancy of Roger Penrose. His theory might be wrong after all, but the simplicity of the idea is there for all to see...

[@ANunes06]

I deeply hope it's true... but that makes me even more deeply suspicious of it. But there's something beautifully simple about "When all you have is quantum fluctuations in an ever stretching, ever flattening universe with no sense of time, a universe is inevitable. And that's exactly what you have at the end of our universe. Maybe that's what there was right before it." It's so easy to imagine, considering the scale of things we're working with. Like zooming in on a fractal.

[@HarryNicNicholas]

@@ANunes06 yep.

[@Lamster66]

The point is that Penrose does go on to explain how his hypothesis is testable by looking for disturbances or ripples in the CMB which would be the evidence of a previous universe or Aeon.. Which is slightly better than using a theory that nobody really understands once we can unify it with one that we know isn't right.

[@feynmanschwingere_mc2270]

@@Lamster66 Which theory isn't "right?" General Relativity? Tell that to your GPS 😂 QM cannot account for several properties of gravitation. Ed Witten: "The reason we know General Relativity is correct is because it is the only theory ever conceived that can explain why gravity obeys an inverse square law. Newton's theory of gravitation does not do that." And quantum mechanics cannot either. Peace.

[@Lamster66]

@@feynmanschwingere_mc2270 Tell it to your GPS? Yes I know how that works Thanks👍 You clearly don't understand that GR works but also has a limit after which it fails. We are talking about The beginning of the universe not time dialation for satellites. ⌚⌚🌌🌌🤣🤣😂🤣😂🤣 Wrong is the wrong word. they are both incomplete . To paraphrase most astrophysicists "The reason we know GR is wrong is we get a singularity!" GR works and is extremely reliable until we get to black holes and T=0 at the Big Bang. Then it doesn't work. This is the same for Newton's classic mechanics it works perefectly well on earth but it has difficulty once you are dealing with Galactic scales. Its not wrong rather its incomplete. Which is why we still teach Newtonian mechanics alongside GR. As it simpler to understand and gives engineers the correct answers on earth. QT is both incomplete and not fully understood. We know this because we dont currently have a GUT. What Penrose points out in his Aeons hypothesis is that "inflation" is introduced to make The mathematics fit the observation of a uniform early universe. It the same fudging as Einsteins cosmological constant was. That fudging of the numbers and the anomaly it threw up lead to physicists hypothesizing Dark Matter. Which is likely real. Penrose doesn't state that he is correct only that His hypothesis doesn't require inflation to work.

[@mickhurley7305]

I asked a cosmologist about my diet. I said I was losing weight and my waist was gettting smaller. He looked at me and said , oh you are shrinking , so you must have been infinitely big once.

[@tonybarry787]

Love it!

[@markostojiljkovic7100]

Its sad that Roger Penrose didnt finish his thought. Its like you try to explain what a computer program is to common folk and he stand up and leaves just as you explained all the 'boring' details and started with actual code meaning

[@LuisManuelLealDias]

there are other videos out there where he explains his idea, if you are interested. It's a fun idea, and he proclaims that there might even be some observational experiments you could do with it, but it's really far out.

[@NondescriptMammal]

It was a bit depressing to see the other cosmologist sitting there looking so put upon, as if he could barely endure listening to Penrose, as if he were listening to blasphemy from a village idiot... and to see the moderator check his watch as a hint to Penrose that they didn't have any more time to listen to what I can only guess they consider nonsense.

[@NondescriptMammal]

I guess there just wasn't enough time laying around in this 14 billion-year-old universe to spare five or ten more minutes to let Penrose finish his line of thinking

[@starfishsystems]

Penrose was wandering here. I was hoping that he would present a coherent and illuminating idea of some kind, or adding a small but perhaps significant piece to the model, but instead he seemed to be just wandering around smelling the roses. That's fine. We all do that from time to time, either as a way of taking stock of our inventory of ideas or as a preamble to developing a critique of some kind. Survey papers are a common example of both exercises, and they're valuable contributions, not because they're offering anything new, but simply toward coherence. I didn't notice that Penrose was particularly intent on offering coherence.

[@SassePhoto]

Penrose has the ability to explain the most complex context of the universe in such a lucid way that one just wants to write down the theory of everything immediately

[@marsovac]

He was cut down at the right time for this audience. He was about to start with conformal theory and how "scale" without time is the same as long as all transformations are conformal, so big = small and therefore another big bang can start. This would be hardly swallowed by the audience. In a mathematical sense I can grasp what he says, however there is only one prediction that comes out of that theory (gravity could leave a mark in the next eon) and so far observations cannot confirm anything (neither astronomical nor the cosmic background radiation studies), and most likely never will - so it is in similar status as String theory: it might be onto something but cannot be neither tested positively nor disproven, it needs better and testable predictions which are more than "there could be something that we might never find". Using math as to explain phenomena that we cannot observe, confirm or disprove is the same as what religion does, not science. Science uses math, not the other way around. "We might never know" is a perfectly good answer to what was before "time itself", and if extraordinary claims are laid down, they also need extraordinary evidence.

[@sevenstarsofthedipper1047]

@@marsovac I am not a scientist but I find Penrose’s theory fascinating. I read his 3 page paper on CCC, and I got his book, Cycles in Time, for Christmas. I struggle with the concept of conformal because this is not my area of expertise. I understand that he is talking about the preservation of angles but like the Escher drawing, everything is compacted at the boundaries. Is he saying that the Big Bang is the compacted state at the boundaries? Help me if you can.

[@junacebedo888]

Penrose says there was no 'time' before the universe. But there was 'eon' . Eon is time. How flip floping could he be?

[@vertigo2893]

@@junacebedo888 (space) time only exists within a (or our) universe. You can not say "before there was time". However penrose thinks our big bang is the same as a big rip in a different universe. A different eon as he calls it, which had its own (space)time.

[@junacebedo888]

@@vertigo2893 God is eternal therefore timeless. Universe is a creation. God is the creator. That universe of Penrose which has no evidence that it exist; will also be a creation

[@fredb2022]

Thank you to our hosts and hostesses. Starting to understand this in installments. Good panelists.

[@rhayat10]

Penrose is right; he goes back closer to the Big Bang than all the other cosmologists. Bless his heart!

[@aaronmarchand999]

It's all fantasy... hopefully I live long enough to see this theory get completely discarded

[@william41017]

@@aaronmarchand999 why is it fantasy?

[@aaronmarchand999]

Because none of it is true, it only exists in the human imagination

[@loz9324]

@@aaronmarchand999 how do you know?

[@davida8119]

So if I get it with Penrose, times' only measure is mass/energy, when everything eventually evaporates with Hawking radiation to massless particles like photons then time itself ends, but this itself leads to a new expansion and therefore a new universe. Love it. And now I just have this vision of Jeff Goldblum saying 'life finds a way'

[@tofu-munchingCoalition.ofChaos]

The metric time (what clocks measure) depends on rest mass. Energy or relativistic mass is not enough to build clocks. But without rest mass the ordering of time makes still sense (as well as things like twice as much time). But it makes no sense to say in one minute (metric time). Why mass faded away at the beginning of the universe was discussed before in the video. The Higgs mechanism "melts away" and particles loos their rest mass. At the end of the universe most of the rest mass is in black holes. They evaporate. But some rest mass is still in a few elementary particles (positrons, electrons, ...). According to Penrose they lose their rest mass because of a complicated reason he avoids in discussions with the public (rest mass is not a Casimir operator for irreducible representations in an expanding universe - discussed in his paper or the KZbin video *Brian Greene and Sir Roger Penrose: World Science U Q+A Session* ). So at the beginning and the end the universe looks has no rest mass (no metric time, hence no size, no scale). So large and small are indistinguishable. And then the beginning and the ending of the universe look identical (that they look the same after rescaling was proven in detail by a student of Penrose under Penrose supervision). So if we apply the same laws of nature to the ending of the universe, it just expands like it always did into a new aeon. The interesting thing about Penrose's idea is, that it needs no new physics. Only the physics which is known but applied to situations nobody had done it before.

[@bmoneybby]

@@tofu-munchingCoalition.ofChaos ya, I've been trying to fully wrap my head around CCC for many years now haha.

[@lesalabs]

@@tofu-munchingCoalition.ofChaos But even if the beginning and end of the universe look identical it still doesn’t explain the big bang itself. What is the exact math that leads to that turning point and at what exact moment does it occur? Why is the critical transition between two eons, the split second we know as the big bang? Even if the end is small it still doesn`t mean that it must have a new beginning over and over again. There`s no guarantee that some quantum fluctuation will lead to a new aeon.

[@tofu-munchingCoalition.ofChaos]

@@lesalabs *What exact moment?* There is no exact moment because metric time is ill-defined there. But there is an exact "moment" in conformal time. It's the time which corresponds to the current metric time infinite future. At that moment you don't need something new (quantum fluctuations, inflation,...) to start the big bang. You just apply the laws of physics to the limit state of the universe. The "big bang" is nothing special. Once you have the initial state (limit state of a past aeon) you don't need something else to trigger it. It happens because the known laws of physics give us the big bang from the initial state (=limit state of a past aeon).

[@user-dialectic-scietist1]

😆😆😆😆😆😆😆😆😆😆😆 And they were there to see it, but they didn't invite you.

[@primovid]

This was excellent, hearing so many physicists explain the big bang theory in their own words and all so surprisingly different.

[@junacebedo888]

.......... so anticipatedly contradictory

[@patricksee10]

And all so wide of the mark!

[@Thomas-gk42]

As always, Dr. Hossenfelder brings it to the point.

[@niks660097]

for me CCC is best possible explanation because it doesn't need wild assumptions like inflation fields etc, it only relies on Dirak's equations and Einstein's GR..

[@McFugo]

Love all these names, this is my kind of video. And can I just say I love those introductory cards for each speaker with a quote and music, it's got "select your character" vibes and I'm lovin it

[@md.fazlulkarim6480]

Almost closer to truth. I liked when Sabine said from where did all come from. The ultimate question.

[@andrewmurray6352]

Are you asking "where has all the truth gone, is that the ultimate question"?

[@susanarupolo2212]

Thank very much to all of you specially to Roger so full knowledge and vitality.

[@tomcervenka3119]

I wish that Sean Carroll and the moderator would have let Sir Roger speak longer.

[@Aguijon1982]

Universe, why are you here? Universe: because I can't help it

[@PilatesGuy1]

5 Stars⭐ for the panelist. esp. in the context of the apparent 24 minute time limit. More, please. Notes: 1. Wanted more Bjorn E. We rarely get to hear those comments/concerns. 2. I'm a Toastmaster trained public speaker and performer, so I totally understand time limits. But I would find it personally impossible to cut off Roger Penrose😀. Side Note: Great tropical shirt on Chris I.🏝. Thanks to all!!

[@vyli1]

> Wanted more Bjorn E. Yeah, no; Bjorn Ekeberg is a philosophy guy, he has no understanding of big bang cosmology and he has no clue what he's talking about. He speaks with some aura of authority on the subject, where he's completely ignorant on the actual mathematics and physics behind it. Don't listen to that guy at all. He's a typical Dunning Kruger effect 'victim'.

[@philochristos]

The Big Bang theory is not about an explosion. Instead, it's about what the universe looked like when it was younger. And what it looked like was an explosion.

[@reasonerenlightened2456]

The audacity to suggest that this amount of insane energy can spring out into existence from nothing is borderline stupidity. Effectively it is a version of the Boltzmann brain theory i.e. there was nothing and suddenly there was an insane amount of energy.

[@philochristos]

@@reasonerenlightened2456 I don't think that's what the Boltzmann brain theory is about. You should check out the PBS Spacetime video on Boltzmann brains. It's a really good explanation.

[@mikehart5619]

Not exactly. If I explode a firecracker or an atom bomb, matter and energy move outward from the explosion into more or less empty space, less if it's on earth since we do have an atmosphere. The Big Bang Model isn't matter and energy moving out into empty space from somewhere but space itself expanding and carrying matter and energy with it. This isn't based on guesses but on observations that can be verified. As far as springing out of nothing, we don't know and maybe can't know how it originally sprung since we can't see back beyond that 1*10^-28 seconds.

[@junacebedo888]

Baby universe or fetus universe look like a 'period' at the end of a sentence. But much more tiny!!!. AND THEN it expanded so infinitely fast. Did they observed that event? NO!!. As Sabine said " we are just speculating. We have so many assumptions"

[@NotASeriousMoose]

​@@junacebedo888"Did they observe the event" is literally the dumbest argument one can make when it comes to astrophysics 😂

[@muditracks3640]

Waiting for this..roger 👏🏻❤️

[@lastchance8142]

It really irritates me that they had the gall to interrupt Penrose. When Penrose speaks, there should be no time restraints!

[@jimmarshall2757]

Where can I find the continuation of Rogers idea of pre and post eon’s, I am fascinated with this idea. For time to exist you need some form of entropy, if there is no motion or decay in the universe, time surely can’t exist.

[@meckerhesseausfrankfurt4019]

What he describes is called "Conformal cyclic cosmology". I think he wrote a book about it called "Cycles of Time".

[@tonelab]

Cool.. I was looking for something to watch 🤓🍿

[@jwarmstrong]

Buy a mirror

[@ryanwinters1766]

Awesome

[@BruceD1776]

There was no t = 0. What is the smallest number greater than 0? Before t = h/E, when t < h/E, where E is the total energy of the universe and h = Planck's constant, different laws of physics predominated. Sub-quantum physics. Penrose at 23:30 "eons".

[@ravichanana3148]

Work needs to be done further for a different picture than big bang.

[@WalkinBeauty278]

Emerging....that description pretty well fits with my experience

[@maxwelldillon4805]

SABINE!!!!

[@Mikey-mike]

So, they're saying they do not have the slightest idea of what they're talking about, which they don't. As with every institution, theoretical physics has been infested by the world parasite moneyjunkies. Obviously, a principle exists which has not been thought of nor discovered (yet). Roger Penrose is the only voice of reason here and deserves more attention.

[@PB-hf9of]

When ever they say beginning, and then within a few minutes what happened , I start brooding what is that time reference frame as as per relativity time is just a relative thing , there is no absolute time. Any one to answer that?

[@markmcd2780]

Some Q's: 1. We have a super-hot dense universe, right? HOW does it cool? Where does the EM go to lessen the temp of everything that is at the same temp? 2. How does a plasma or a soup of protons & electrons create spacetime? It seems to me spacetime either already existed or there is something VERY fundamental not being considered. What can a universe expand INTO? What boundary does the temperature push out to allow cooling? 3. How can there be neutrons at the start? Neutrons have a half-life in a few minutes PLUS you're talking non-charged matter which would not be subject to EM effects. How would protons join neutrons when the neutrons vanish almost straight away? If you propose neutrons are being created by proton-electron collisions, you wind up with a universe that has a very short lifespan. 4. Where does Inflation come from? See, Inflation is a magic, invented solely because the maths of the Big Bang does not produce the universe we see, so they invented Inflation instead of starting over with a new hypothesis. So where does this magic come from & why did it go away?

[@mattlewis5095]

A bit frustrating at the end, this. Penrose usually includes his point that if you can't measure time (with just photons and maybe gravitons in existence) you can't measure space (so to speak, I'm not a physicist), which leads to a new big-bang making singularity - and the creation of a new 'aeon' universe. This, he thinks, has always been the case. In terms of Hawkins and black holes (which he briefly mentioned), he adds that the way they finally die (leaving a dispersion of photons) could be evidenced by us in the microwave background of the new universe (or aeon). Hence we can possibly see evidence of what happened before our own big bang! Hope I got that right.

[@TheEmergingPattern]

Sean brings it to another level, all is information. Roger's more intuitive.

[@mattlewis5095]

​@@TheEmergingPattern Well Sean Carroll continued the introduction of course then talked very briefly about emergent approximate reality and then about 'times arrow' (as seen by 'us') as stemming from a 'symmetric' larger universe that parallels ours (which certainly isn't 'set in stone' lol). I think that at this stage of his great career Roger Penrose has more than earned the right to do whatever he wants with his time, but though I always love hearing Penrose, I most enjoy Sabine Hossenfelder's arguments in general (she was in the video directly after). In her own brief moment she mentioned dark matter and dark energy, and it's because she feels that more time and energy should be spent honing the core models that people base their speculative theories on. Hossenfelder isn't against theoretical physics at this level (and she's a Penrose admirer and theoretical physicist herself), she just has a very practical approach, and she talks a lot about the now really-long stagnation in any major advancements in physics, and what she's come to see as a misuse of scientific funds in continuing to advance particle colliders (building bigger etc largely in the hope of bumping into new things) and in maintaining such a strong focus on trying to develop theories that haven't gone anywhere for decades now, like string theory.

[@TheEmergingPattern]

@@mattlewis5095 oh yes, can imagine proving dark matter is an earning model. Ruling out the theories that can do without it.... Perhaps, I'm not an expert

[@mattlewis5095]

​@@TheEmergingPattern I did wonder about theories that could replace the need for dark matter etc, but my point is that most of if not all of these kind of theories either progress or depart from Newton and Einstein and the standard model.. and to some degree they probably have to, to be taken seriously. I'm probably not explaining this well (I'm certainly no expert either), but there could be a few paradoxes in there. I think there is money to be earnt (private and public) in all areas of science - and people like me (who don't think science will 'save us' in my case) will like to keep half an eye, when we can, on where it is in general going. Hossenfelder's argument, which seem to be to focus more on the core of what we actually use, makes a lot of sense to me.

[@TheEmergingPattern]

@@mattlewis5095 yes, I believe this new core you mention is also part of a new theories from "Erik verlinde" or "Wolfram" . The rules of relativity and Newton are within the boundaries of it and agree with observations so far. However, being an amature I can not say more about this dark stuff and probably better to focus on relevant and praktical things. Time is precious, but we get sucked into these media bubbles once in a while. It's interesting but also a waste of time

[@jok2000]

Time running backwards is absurd for an abundance of reasons, #1 being lack of information to actually run backwards.

[@ffggddss]

In this context, it's really no more complicated than when you turn your head around and see a roller coaster whizzing down an incline at 60 mi/hr, and you look at the ups & downs of the track it's on, and you can figure out from that, just where it was at any time in the past, back to the endpoint of its initial launch. You didn't need to actually see it before you turned your head. Fred

[@espaciohexadimencionalsern3668]

Same old thing but still have to watch till new brake throughs come around - hope it wont take much.

[@MrTeff999]

Break

[@nagualdesign]

_*Breakthroughs_

[@NondescriptMammal]

Don't hold your breath, there is no good reason to expect that better answers are imminent, just more and more speculation. Even JWST and further improvements on observational abilities do not hold the promise that they are often said to.

[@scientistcraft]

How ever they seems very diffrent subjects.

[@TheFith67]

''Your're not allowed on this stage unless you agree with the Big Bang!'', sounds more politics than science to me.

[@fins59]

A few hundred years ago: "You're not allowed on this stage unless you agree the Earth is the center of the Universe".

[@TheFith67]

@@fins59 Always politics

[@NondescriptMammal]

@@TheFith67 If not politics, it is at the very least dogma, and no theory should be treated as dogma. Skepticism is supposed to be central to good science.

[@TheFith67]

@@NondescriptMammal Yes exactly. Only beliefs cower from it. They seem to be scientists of great faith. I'd even say a bit fascist too.

[@NondescriptMammal]

@@TheFith67 Yeah it was pretty pompous and presumptuous for him to say that, as if he is the self-appointed authority on who gets to participate in a debate on the subject. Especially in cosmology, where they try to surmise what happened billions of years ago, from a very limited and tenuous set of data. Any cosmological theory necessarily requires a number of assumptions. And it's not the kind of science where you can do repeatable experiments to prove a theory, you're almost entirely stuck with whatever data can be gleaned from EM radiation received from distant celestial objects.

[@ronaldbrunsvold5632]

I kind of remember a prior Aeon, before I became photonic.

[@enriquelaroche5370]

"The Geodesic is a cyclic field. " cyclic events are natural and no one can see beyond the zero crossing of an expanding universe. But a collapsing universe is what was before the big bang.

[@robinsuj]

I don't know why, but I am always surprised when I see that Dr. Sir Penrose is still alive.

[@captainbeefheart5815]

His superpower is that he doesn't die

[@monian2877]

why is this guy not allowing Penrose to continue?

[@bobbabai]

Ekeberg said the big bang theory is where the lines between physics and metaphysics are most blurred. That statement really bothers me because it assumes there are metaphysics. We know there is physics (which is our best explanation of the reality of the universe - what we can detect) but we only speculate on metaphysics. My understanding of metaphysics is simply that it is aspects of what we can see in the universe that we don't understand and some people might say they're not understandable. That's just speculation. It throws out the idea of saying "I don't know" when you don't know, and then saying "I'm going to try and find out".

[@junacebedo888]

Another word for metaphysics is 'imagination'

[@bobbabai]

@@junacebedo888 no, it isn't

[@junacebedo888]

@@bobbabai ....bad thoughts?

[@Vidar2032]

If the universe has been everywhere all the time, and the big bang happend everywhere, it must mean that the universe has never been smaller in the past, nor at the moments short after the big bang. Just denser, and still without boundaries.

[@adamc1966]

True.

[@bballen3097]

The big bang appears to affect the observable universe but we can only speculate about the unobservable universe.

[@tracyraven7444]

Everyone seemed so nervous and rushed ... damn you time 😅😅😅

[@johnmoncrief9209]

WHERE DID ALL THAT COME FROM HOME DEPOT

[@twillis449]

I have no idea how one discusses the Big Bang in 24 minutes!

[@danphillips670]

Scientific Theology Big Bang model. The theory itself was originally formalised by Belgian Catholic priest, mathematician, astronomer, and professor of physics Georges Lemaître.

[@danphillips670]

“In science, convictions have no rights of citizenship, as is said with good reason. Only when they decide to descend to the modesty of a hypothesis, of a provisional experimental point of view, of a regulative fiction, maybe they be granted admission and even a certain value within the realm of knowledge-though always with the restriction that they remain under police supervision, under the police of mistrust. But does this not mean, more precisely considered, that a conviction may obtain admission to science only when it ceases to be a conviction? Would not the discipline of the scientific spirit begin with this, no longer to permit oneself any convictions? Probably that is how it is. But one must still ask whether it is not the case that, in order that this discipline could begin, a conviction must have been there already, and even such a commanding and unconditional one that it sacrificed all other convictions for its own sake. It is clear that science too rests on a faith; there is no science ‘without presuppositions.’ The question whether truth is needed must not only have been affirmed in advance, but affirmed to the extent that the principle, the faith, the conviction is expressed: ‘nothing is needed more than truth, and in relation to it everything else has only second-rate value.'” -Friedrich Nietzsche Convictions are more dangerous foes of truth than lies. Friedrich Nietzsche Can you say"Bias."

[@LazarosKosmidis]

@@danphillips670 In science, convictions have no rights of citizenship? Ask (google) Velikovsky!

[@novakingood3788]

I'm a bit confused by David Tongs explanation. He talks about going back in time and atoms melting followed by the nuclei then the neutrons and protons themselves melting followed by the Higg's Boson. Surely these are all condensing/ coalescing/solidifying as we move forward from the so called big bang which leads to me to wonder about the creation of these particles.

[@salmanuel4053]

So the big bang isn't about how the universe started. It's just about how conditions were a while back. I guess you can't argue with that.

[@cango5679]

The big bang theory is a great - well - good comic show. That's about it.

[@gwillis9797]

So, where is the starting point? Where did the Universe begin? How did ( space ) begin? How did gravity begin?

[@richblacklock]

Why is that usual graphical depiction directional? Is that part of the theory - that the expansion was directional? Why not in all directions from a singularity?

[@outdoorcoaching]

My interpretation The model depicts the start of time, as in a timeline. We always use timelines, and no such things as timespheres.

[@ck58npj72]

Every place is the center of the universe.

[@zefallafez]

I think it’s like a tree of evolution diagram.

[@nagualdesign]

No, it isn't directional. The x axis in that diagram is time (from left to right). Each 'slice' along the y axis is a two-dimensional representation of the observable universe at any given moment (although we can actually observe the CMB of the early universe from here and now).

[@NondescriptMammal]

@@ck58npj72 Even that schematic diagram has a center point all along its time path... if you took one slice of any part of it, it would be a circle for which a center could be found

[@michaelhunte743]

It could be that there was an expanding dimensional shift that at a certain point in time matter became an emergent property of an accelerating universe.

[@gregalexander8189]

What time of day was it when the universe began?

[@bmoneybby]

Every time I hear "our universe started in a hot dense state", I hear The BIG Bang theme song. Very annoying..lol

[@KristopherNoronha]

probably why half the people got here to begin with... and left 5 seconds later :D

[@Earwaxfire909]

I like the Penrose paradox. If all there is are photons, then because there is no mass, so there is no time, and so there is no space. And so where does all of that energy go? Bang! It starts over again.

[@philochristos]

It sounds like handwaving to me. The way I heard him explain it one time, if there's no space, then there's no difference between things being close together or far apart, so no matter how spread out things are, they might as well create another Big Bang from a point. This strikes me as being pure philosophical speculation.

[@Earwaxfire909]

@@philochristos In the reference frame of the photon what he said is true. It's not handwaving at all. Mass has a clock so it observes and measures space time. It is hard to grasp but if all of the mass in the universe decays into photons, there is no space time.

[@nagualdesign]

@@philochristos It's a simple fact that in the absence of matter an extremely dense collection of high-energy photons is indistinguishable from an extremely sparse collection of low-energy photons. Having said that, we don't really know with any certainty that the universe began with nothing but photons. We only know that that's how it will probably end.

[@l.m.892]

He started with hydrogen and bypassed the fact that electrons and protons had to form before there is hydrogen. Minor oversight, but everything that follows relies on the process of electron/proton formation. Missed a step. Without quanta, there is no quantum mechanics.

[@pobinr]

Why is someone hitting a synth in the intro?

[@clavo3352]

Wow! My brain turned to glue. There was movement for a while but eventually it set... like glue.

[@jiminverness]

"All the galaxies are moving away from us" Andromeda is moving towards us...

[@vasile.effect]

And even galaxy clusters collide...

[@mikehart5619]

Galaxies within our Local Cluster aren't moving away from us by expansion. They are gravitationally bound to us and Andromeda happens to be moving toward us. More correctly, it should be most of the galaxies in other clusters are moving away from us and the further they are away, the faster they are moving.

[@emak4558]

Why do you play irritating intro music that drowns out the speakers voices? Do you think that is helpful?

[@rondai4019]

So hard to buy into the reverse time theory of Mr. Carroll...

[@philochristos]

I agree. I have been trying to understand it, and while I think I have a vague idea of what he's saying, I'm not entirely confident I've got it right. But what I think he's saying is that he DEFINE's time as the direction of increasing entropy. He believes that for the universe to have had a low entropy at the beginning, it had to have reached that low entropy by decreasing entropy prior to the beginning of the Big Bang. Since entropy was decreasing prior to the Big Bang, and since time is defined as the direction of increasing entropy, it follows that time was running backward prior to the Big Bang. But this, it seems to me, is just semantics. Time wasn't REALLY going backward prior to the Big Bang. He's just DEFINED his terms in such a way as to say time was going backward. But what was REALLY going on is that time was moving forward, but it just happened to be the case that entropy was decreasing. This is possible if you take the statistical approach to entropy. Entropy tends to increase because statistically it's much more probable that it would increase than that it would decrease since there are vastly more random configurations that particles can take than there are ordered configurations that particles can take. So the decrease in entropy prior to the beginning of the universe was just a rare statistically anomaly. That's my take on it, anyway. Like I said, I may have Carroll all wrong.

[@rondai4019]

@@philochristosWhat really troubles me is his claim about the multiverse that in some universe, their our past is their future and their past is out future.....I don't believe that could be true with any plausible physics...

[@ZeroOskul]

So hard to buy into anything ever said or done at any time by Mr. Carroll

[@hyperduality2838]

The Big Bang:- Contraction to a point or singularity implies null homotopy (topology). Non null homotopic implies a second point/singularity = duality. The big bang is a Janus hole/point (two faces = duality) or non null homotopic -- Julian Barbour, physicist. Topological holes cannot be shrunk down to zero. Homotopic equivalence = duality. The future is dual to the past -- time duality. We remember the past and predict (syntropy) the future. Space is dual to time -- Einstein. Continuous (topology) is dual to discrete (quantum). Duality is the bare minimum for any metaphysic of reality! "Keep your ideas as simple as possible but no simpler" -- Einstein. Energy is dual to mass -- Einstein. Dark energy is dual to dark matter. "Always two there are" -- Yoda.

[@bobblacka918]

We do not "measure" time because there is no time to measure. We create the illusion of time from the mechanical movement of matter in space such as the pendulum of a clock, the vibration of a quartz crystal, or the oscillation of a Cesium atom. Einstein alluded to that when he said the following: "We say a train is on time when it arrives at the station when the hands of a mechanical clock are in a particular position." Thus there is no absolute time and therefore we cannot either go forward in time nor backward in time. We can only live in the present. It is not time that controls the motions of the planets, rather, the motions of the planets define what we call time, and thus, all motion is relative to some other motion in space.

[@sonarbangla8711]

For cosmologists and physicists to explain big bang, we need to explain the various infinities involved, like infinite density, infinite time, infinitely small singularity etc. GR and QM gives us different perspectives, like when we approach a black hole singularity, we need infinite time. The big bang is also thought of as a singularity and if we try to approach it, it will take us infinite time, so what was there before the big bang means what happened before eternity and thus doesn't doesn't have any significance. QM gives us very important and interesting insight. Heisenberg's uncertainty principle enables us to conceive quantum fields (Feynman). De Broglie's wave and Schrodinger's wave function shows us how the wave collapse into particles, upon observation by an intelligent conscious observer, so when Hawking conjectured the pair production of virtual particles, one falls into the BH while the other is expelled as a real particle, implying that a conscious intelligent observer collapse the field to produce various particles of the standard model, fine tuned as the parameter space. Maldacena conjectures that the whole universe is a QC function, self error correcting, deterministic, unitary evolution of Schrodinger's wave function, of unknown algorithm, implying intelligent design with the divine purpose of creating life.

[@nagualdesign]

In QM the term "observation" doesn't actually imply a conscious, intelligent observer. A wavefunction can collapse due to interaction with a particle, in which case the particle is the 'observer'.

[@sonarbangla8711]

@@nagualdesign Upon interaction with a particle a state goes into one of infinite states, until you measure, when the state collapses.

[@nagualdesign]

@@sonarbangla8711 All of our measurement apparatus are made of particles, even when we're not looking. Wave functions collapse due to interaction with the external world, regardless of human intelligence or consciousness.

[@sonarbangla8711]

@@nagualdesign Evolution of the whole universe is a quantum phenomenon, it is all waves and quantum fields.

[@junacebedo888]

Not all believe 'infinity' is a reality

[@arcmode]

this debate needs Wallace Thornhill

[@LazarosKosmidis]

Haaaa ha ha ha! They will run like mice when the cat finds their hide out!

[@d1psh1tc1ty]

So what is fundamental? Information (logical substance), and illogical substance, whatever that is.

[@vasile.effect]

As far as I know no one has ever observed shrinking or dissapearing galaxies. So no, galaxies are not moving away from us. For example Andromeda seems to be moving closer to us.

[@simonbode7356]

I know that we can remember the future. At least for very small time scales.

[@nmarbletoe8210]

i think so, it would explain a lot

[@taxidevogr]

It's called 'foresee' and you can in limited small time scales and for limited parameters. That's why you can't foresee the weather for example, too many parameters.

[@mrjagriff]

First guy sounded like his speech was going to last as long as the universe is old 🙄

[@Zhavlan]

Hello. Question from a technician. Science people. Is it difficult to change the frequency of light to the "Ka" range in Michelson's 1881 experiment and use this experience in transport to measure the speed of transport? If you are at rest inside the DGF, then relative to you the speed of light is constant. If you are in motion in the DGF, then you break the symmetry and break the speed constant of light with respect to yourself. DGF - Dominant Gravitational Field.

[@akinsamuel2007]

Dark matter is a misnomer. I knew they would find no dark matter "particles". As Penrose said When you invent a theory to explain one specific idea that's not relevant to anything else its likely to be wrong. There is no reason for dark matter in the universe. Even its name is a misnomer. If you call something "matter" you're going to start treating it like it. You then invent a "new kind of matter". It's just another story and the universe doesn't care. Discoveries are made when the universe tells you "Yes" or it tells you "No". You will find nothing when the universe tells you "Whatever."

[@vertigo2893]

Thats just silly. First of all, there is no way you or anyone knew we wouldnt find dark matter. Yet. There is no way anyone knows it doesnt exist, there are still plenty of candidates that havent been ruled out, sterile neutrino's, simps, axions, even primordial black holes. We call it dark matter because if our theories are correct, then there has to be something, whatever that may be made off. That doesnt mean no one is looking for alternative theories. Plenty of attempts at modifying gravity. Nothing so far comes close, but if anyone comes up with a theory that explains observations better than our existing theories and dark matter, we will just drop the word and accept it doesnt exist. Until then, our current theory of gravity is the best we have, and dark matter is a perfectly good word.

[@NondescriptMammal]

@@vertigo2893 Actually the term "dark matter" is problematic, as it is strictly a place holder term for a hypothetical substance, for which the ONLY evidence we have is that certain celestial observations do not conform to our expectations and cannot be explained by our current knowledge of physics in light of the visible matter we can see. It is a term that presupposes the existence of an entity that we do not know exists. And recent data has actually weighed in favor of modified gravity which doesn't require any "dark matter". Sabine H. has worked on the dark matter problem for years, and was strongly inclined to believe it was most probably due to an undiscovered particle, but recently she has publicly said that she is now more inclined toward the MOND theories and is no longer so confident in dark matter's existence.

[@eddieheron1939]

Not ‘getting’ his references of his mentioned atomic components “melt” - they haven’t yet existed!

[@MrTeff999]

Maybe Penrose is right that the universe expands until nothing is left but photons, and then repeats…. But we have no evidence to support that idea.

[@makhalid1999]

What is this, a crossover episode?

[@scientistcraft]

Quantum theory is simmilar needle that sew time space to gether so will connect all the paricles are connected together in very huge field of space-time that

[@jimturner4937]

So there was no gravity holding things together before expansion. Doesn't make sense to me. How does gravity fit into the early universe.

[@supersmart671]

I am just amazed at the metaphysical (should be empirical, reality, truth, ...) assumptions that are made here. Hope others are able to see it.

[@junacebedo888]

If a person overthinks, his metaphysical thoughts are actually hallucinations

[@supersmart671]

@@junacebedo888 this itself is a metaphysical thought...

[@junacebedo888]

@@supersmart671The Illogical is also metaphysical. Schizophrenia and other mental insanity are also metaphysical. Multi-verse or string theory, I think, is just pure and plain craziness

[@supersmart671]

@@junacebedo888 Is your own statement Metaphysical?

[@junacebedo888]

@@supersmart671 My statements are utterances

[@fredjones7307]

We know "exactly" what was happening one minute after the big bank...I need to throw some more corn in the coup, the chickens are getting agitated..

[@cooksoni.a]

its very difficult for me to visualize the big bang, because i cant get past the idea of something exploding outward from a singular point within space. but thats not what happened. it happened everywhere at once with no center and no edge, where everything was more dense with stuff and that stuff began to get less dense. but how is it getting less dense? the only way i can imagine it is a dense collection of matter within a space that then diffuses throughout the space, but thats not the case with our universe, because there is no external space that it is diffusing into.

[@noelwos1071]

a new branch of physics called singularity physics will have to be opened soon!

[@JoeWyley]

I would postulate that the big bang was an error in a larger substrate. We exist because of a breakdown in the larger relativistic substrate. We are byproducts of higher dimensional decay.

[@bwoutchannel6356]

The whole premise is incorrect in that describing the melting of Atoms, electrons, nuclei, protons, neutrons etc in a reversal of actuality and forward occurrence is inane science. Sort of like describing the physics of a Trampoline when a person jumps onto it and describing it until bit by bit their full weight as reached maximum compression . The sound effects are neither relevant as no ears existed as one says if a tree falls in the woods does it make a sound. Back to the beginning of my point, which is before there was anything there wasn't a thing but the ending did begin.

[@peterpalumbo1963]

Is it possible quantum mechanics did not exist in the beginning, before particles formed?

[@taxidevogr]

They didn't, as general relativity didn't. That's what I remember from a video

[@ZeroOskul]

1:30 See: "Finding Forrester"

[@GreenLight11111]

Could there be wolrm holes connecting other universes to each other?!?!

[@gkelly34]

I love roger penrose's theory. The other's don't feel right but his just rings true somehow

[@morrienb]

His idea that if clocks are absent the scale of spacetime is undetermined is attractive because then a new quantum fluctuation could occur which form a next big bang with a new scale of spacetime and a new low entropy value. Resetting the scale of spacetime seems logically possible, but this should also be demonstrated for entropy.

[@BlastinRope]

@@morrienb hmm yes. The interfeterence of electrically encabulated fields carries dire implications for the bourgeosie.

[@pseudonymousbeing987]

@@BlastinRope I actually thought you were one of those electromagnetism conspiracy theorist dudes for a split second

[@gkelly34]

@Stinky Piece of Cheese I couldn’t disagree more. Einstein believed all of space and all of time (past present and future) were created at the moment Of the Big Bang. Besides a lot of theory is belief and intuition until it’s falsified

[@ffggddss]

"... his just rings true somehow" So did the Steady State Theory of Hoyle, Gold, & Bondi (which Penrose alludes to), until the CMBR was found. "Nothing in life is quite so tragic as the murder of a beautiful theory by a brutal gang of facts." Ultimately, we are compelled to listen to what the universe tells us, by way of observations, regardless what we would like to be true. If we're lucky, observations will support our "favorite" theories. If we're not, we'll have to adopt a new "favorite." Still, I share your desire for a theory that "rings true." Fred

[@chrisvawdrey2810]

Is dark energy the driving force of entropy towards absolute zero

[@stelissa4039]

I wonder if 'dark energy' is information. As more information is generated, the area of the boundary of the Universe has to expand to accommodate it.

[@NondescriptMammal]

They truly have no solid idea of what dark energy is.

[@crawkn]

If black holes will be the last things to exist, dissipating all of their energy as photons, everything else would need to have entered a black hole at some point. Has it been demonstrated that everything must? (Note to audio producer, the interstitial music is too loud.)

[@alexisjardines3384]

Time is the key, but you have to understand its nature.

[@junacebedo888]

Science said Time space and the Universe began. (Before) that, time did not exist

[@fredjones7307]

Carl Sagan said "extraordinary claims require extraordinary evidence"..The new religion, Astrophysics. I forget the astrophysicist who said this "if we get it 20% correct that's a result".. probably wouldn't reduce his pension to 20% though..

[@junacebedo888]

Carl Sagan is idiotic in saying that statement. "Extraordinary or ordinary claims only require sufficient evidence" is the correct rule

[@bballen3097]

@@junacebedo888 Sufficient evidence would need to be extraordinary for extraordinary claims.

[@junacebedo888]

@@bballen3097 Nope. Adequate proof would suffice. Hiroshima was extraordinarily destroyed by an atomic bomb. Einstein's 'E=mc (square) is enough proof it happened

[@NondescriptMammal]

@@junacebedo888 What a terrible example. There is nothing extraordinary about the claim that Hiroshima occurred. It was seen by innumerable witnesses as it happened. We are talking about extraordinary claims, not extraordinary events. If you claim to know with certainty what exactly happened billions of years ago, based on relatively scanty evidence, with a number of built in assumptions baked into it, and your claim also doesn't satisfactorily answer fundamental questions inherent in it... that is an extraordinary claim.

[@junacebedo888]

@@NondescriptMammal I disagree on the age of the universe based on the speed of light

[@ThalesPo]

8:43 "Time started 14 billion years ago."

[@NondescriptMammal]

That's a perfect example of a metaphysical statement. There is no possible way for any physicist to rightly claim they know that with any degree of certainty.

[@laurenth7187]

Penrose, how do a BH evaporate since nothing ever can escape from it (paradox) ? Then, How is the universe "aware" that is is empty from any mass, then what about the virtual particles created from the energy of the void... ?

[@rpgspree]

Things below the event horizon can't escape. Above that boundary, the escape velocity is less than c (the speed of light). Things escape from above the horizon all the time, it just requires higher and higher energies for mass particles to do so the closer they get to the horizon. These extremely high energy plasma jets black holes eject from their poles are how they were first detected. As the escape velocity approaches c, only massless particles such as light can escape. As for evaporation: the short answer is that due to quantum randomness, photons can be generated just above the event horizon and escape, taking bits of energy from it. This is called "Hawking Radiation". At the moment, the universe is putting more energy into it than what comes out in these photons. What Penrose was saying is that eventually the universe will become so defuse and cold that the energy balance will flip, more will leak out of the black hole and eventually evaporate. Don't worry though, that's an unfathomably long time from now.

[@laurenth7187]

@@rpgspree Pairs of photons are created, and 1 is captured by the BH. So the BH gets the same energy he puts into the escaped photon... ?

[@rpgspree]

@@laurenth7187 It still loses the energy of the escaped photon.

[@janklaas6885]

📍15:07

[@sethcommichaux9746]

How do we know that red shift isn't caused by light losing energy as it travels through space?

[@maalikserebryakov]

Where does the energy go ? Up your arse? Secondly, Even if that was true there are still two observational facts (1) Redshift is GREATER the further the source of astronomical EM radiation is (2) the above happens in absolutely every direction EM radiation is measured from anywhere on Earth There is simply no way to avoid the proven fact of Universal Expansion. New space is coming into existence as we speak. If you went into deep space far away enough from any powerful gravitational fields , and drew an an imaginary of 1m^3 There wouldn’t be 1m^3 in that volume for long. You’d get MORE volume and more space due to Universal Expansion

[@donnievance1942]

Light doesn't lose energy as it travels through space, it only becomes more dispersed. The individual photon does not lose energy. It cannot lose energy except by collision with particles. The incidence of that happening through intergalactic space has already been calculated and found to be too negligible to account for red shift. in any case, light that has experienced collisions will be dispersed and not observable as an image that can be analyzed in respect to red shift.

[@laika5757]

Can someone please be generous enough to explain to me the statement "the Big Bang did not start in a particular region in space". I cannot get my mind around that.

[@nmarbletoe8210]

it started everywhere in space, but one point in time. everywhere was smaller back then.

[@NondescriptMammal]

The usual answer is because "space and time did not exist" before the event from which the Big Bang evolved, and that all of time and space were contained in that "singularity"... I find this answer completely unsatisfactory, and have looked for better explanations, but have never found a coherent explanation. If they say the universe is expanding, and that it started from a smaller extent than the vast universe we have now, it seems geometrically impossible that there is not a location in our current universe that would correspond with the location of that event. Even if we accept the metaphysical explanation that "space itself is expanding", there would still be a geometric location that would correspond, you would think.

[@booJay]

Question(s): If we can simply rewind the clock back to infer what happened in the past and currently the furthest reaches of space expand faster than the speed of light (and presumably continue to increase to infinity?), wouldn't that mean space expanded slower in the past and eventually would slow to a crawl, then stop? Edited: I guess that's where inflation is hypothesized to have happened, but my understanding is that's only a placeholder for now until we gain evidence to support that that's what occurred before the hot big bang.

[@vlexar80]

Small insight I thought on why did something come from nothing. Why not just nothing forever? When imagining Nothing you assume there must be no "stuff" and no energy. So how would something come from this? Wouldn't the natural state of Nothing at that point be for no actions to happen? In my thought its correct there is no energy or any "stuff" in nothingness, but the natural state of Nothing would still have entropy and since there was no energy or any other force to stop it, Nothing split in to Nothing AND Something(big bang and then the full universe). Which was more of an equilibrium.

[@NondescriptMammal]

The paradox of something from nothing is always glossed over, and I have never seen a serious attempt to explain it scientifically, or to even explain how it is conceivably possible.

[@iamhe999]

what is the point here? the statements or the loud music?....... please no music when people are talking... show some respect.. fire the sound/mix engineer showoff... for lack of judgement..

[@ghoshdebajyoti210]

...Newton...Einstein...Dirac....Hawking .....Penrose......