Before the Big Bang 4 : Eternal Inflation & The Multiverse 

Awesome documentary. Thank you for not dumbing it down. I've shared it on social media forums where I think there might be interest. It deserves to be widely seen.

Wow, great videos Skydivephil team!! I cannot believe that YT hasn't brought these up to me over the last decade of watching mostly astronomy based videos. It's only now when I've taken an interest GMS, cosmicskeptic that your videos came up. It's gonna be a skydivephil binge this weekend!! Thanks so much!

Finally someone is asking physicists follow up questions about competing theories rather than just giving them 10 minutes to lecture! It was great to see others' response to Penrose's CCC.

This is fantastic. I have been lamenting the general lack of intermediate level documentaries (for lack of a better term) on cosmology, and this really seems to fill that void. Hope you one day have the chance to interview Steinhardt/Turok in the same way you did here with Alan Guth.

there was a young lady called Bright whose speed was much faster than light she went out one day in a relative way and returned the previous night

Major increase in production value from episodes 1-3. Great work

The best thing is, that it goes deep, without being complicated. The questions are interesting and the answers understandable. Thank you very much to you, your team and to the physicians. looking forward for new videos

Binge watching these interviews. I appreciate the skill of interviewer in that she's familiar with these topics. It's refreshing to see interesting and in depth questions being asked that challenge the interviewees.

Thanks for this, the work you guys are doing is so special. I love how you guys present the question and let the people being interviewed answer and explain.

The presenter's speech, just the syllables she hangs on for just a half impulse longer is absollllutely lovelyyy.

I try to watch and listen to all of Alan Guth’s lectures and videos that i can find - i find him charming & fascinating.

Fantastic. Much more accessible than a traditional lecture.

Wow thank you for this. The table of contents is wonderful too! Please do more

Thanks for providing such an in-depth look at a really fascinating subject. I loved the enthusiasm of Dr. Guth and Dr. Nomura!

*Hi. Please could you add subtitles to this video like the first part, or at less upload a transcript of this? My mother language is not English, and it's difficult for me to understand this language just listening this. Thanks so much!!*

Happy to find out some cutting edge science presented at a deeper quality level. I'm subscribing now. Thank you so much for your work and keep going!

This series is stunning! Very well done. I want more!

These videos have really good production value for having such few subscribers. It needs more

Unexpectedly deep in its treatment of nuances! Excellent.

Best documentary on RU-vid!! Fascinating stuff!!

We've learned a lot in the last 100 years. Imagine the next 100!

You guys-and gals - are impressing me also- really informative, understandable by a layman and yet without losing the essential science- Bravo

thanx for the upload, i was reading wikipedia once more about eternal inflation and thought lets check youtube if there is something new about it and bam! you made my day..**

Excellent! Thank you. I love her Schroedinger's Cat shirt :)

Interesting so does a contratemporal or bidirectional arrow of time (37:00) suggest a time reversed symmetrical mirror universe? Would this be a mere temporally mirrored universe or would this mirrored symmetry also hold spatially as in a time-space continuum?

Amazing docos guys, really great.

anyone know the soundtrack at the very beginning of the video? I've heard it before but would like the name!

love it I subbed.

Thank you for your wonderful videos.

Completely answered some of my questions never answered by any other few two physics video ever wow

Such compelling information. I loved watching every bit of it.

Excellent!

Amazing content !

wonderful series! thanks ;)

I think I'm in love with the hostess!

A little bit or work on some of the transition editing (some of them felt choppy), but good, solid, information.

Would love to hear your thoughts on Roger Penrose CCC theory.

The Dark Star Cosmology Model - An Alternative to Inflation Theory ***** In this Cosmological model the Big Bang is caused by a reversible, adiabatic reaction from a maximum energy phase of spacetime into a pure radiation phase consisting of grand-unified bosons and gravitons. This decay reaction occurs in flat spacetime. It is completed during the early part of the Planck Epoch so that by the Planck time what emerges is a flat, homogeneous radiation phase. The initial phase of spacetime is characterized by the Planck density and the highest attainable Hubble constant for flat spacetime. This initial state is completely homogenous and it may be a perfect crystalline state devoid of defects, i.e. a very low entropy state. The thermodynamic properties of the maximum energy phase of spacetime are given by the Planck units (T, P density, volume, mass, and a proposed value for the Planck entropy), which suggests that the fundamental constants of physics emerge from the thermodynamic properties of this phase of spacetime. In addition, the maximum energy phase of spacetime would form in the core of dark stars (black holes). The existence of a core allows the dark star to grow faster than it evaporates eventually reaching a critical size where it de-stabilizes and starts the rapid Big Bang expansion. This continued growth of dark stars may due to the interaction of strong magnetic fields produced by the core with the surrounding spacetime. For example, strong magnetic fields near the core could produce Higgs bosons from spacetime and these in turn decay into quarks and leptons that contribute new mass to the core. The Planck charge of the maximum energy spacetime quanta and the spinning of the core are the proposed cause of these fields. ****** This Cosmology model is a type of multiverse system where all universe systems have the same basic evolution and bulk thermodynamic properties. Each universe produces billions or more of the seed dark stars that create future offspring universe systems. The growth of a seed probably takes several trillion years, which creates a great separation between any two seed dark stars. A multiverse system begins with a parent dark star. This parent may form from the collapse of a Bose-Einstein condensate of the ground state phase of spacetime, i.e. dark energy as the Cosmological constant. The BEC parent dark stars are expected to form in regions of the infinite ground state of spacetime which are remote (and unentangled ?) from existing multiverse systems. In the dark star Cosmological model an infinite number of eternally reproducing multiverses exist within an infinite flat four dimensional spacetime which has the ground state energy density. These universe systems are never expected to collide. ****** Spacetime is quantized by Planck volumes and its expansion is driven by the creation of new spacetime quanta. The rate of spacetime volume-quanta creation depends on its energy density. The Planck volume-quanta of flat spacetime form a geometric tiling that fills three dimensional space. The concept of the arrow of time could emerge from the irreversible expansion of pure spacetime in its flat ground state. A possible mechanism for this expansion could be analogous to the Casmir effect. Quantum fluctuations cause small density waves in the ground state phase. As a result of these waves the Planck volumes can undergo minute density changes on the order of the Planck time. However, about every 9 billion years constructive interference of these density waves produces a doubling of the ground state density within a Planck volume, i.e. a metastable state. This event triggers the creation of a new ground state spacetime quantum with the original flat density. The 9 billion year figure comes from the Hubble constant that is calculated from Relativity theory using the density of the ground state, e.g. Planck (2015) CMB studies. The above process also may be somewhat analogous to the spontaneous creation of quarks from the ground state by the action of the strong force. ****** The connection of this picture of spacetime to string theory could be the result of a series of projections of the energy state within the Planck volume onto the 2-dimensional surfaces of the geometric tilling. Somewhat similar to the Holographic principle, the idea is that this projection can be made without any loss of information. Then we repeat this projection of the energy state from the 2-d surfaces onto the 1-d edges of the tilling element without any loss of information. It is the projected energy vibrations of these 1-d edges that would be described by a type of string-lattice theory or perhaps string network condensate theory.

Inflation or expanding universe seems to be triggered by some chain reaction mechanism, perhaps of matter anti-matter annihilation or instant transformation of magnetic mono-poles. Nima's conclusion of super symmetry on small scales, breaking up on larger scale, may be related to inflation/expansion.

And the KSP (Kerbal Space Program) music on the background 😅

RationalPoet.... As a layperson, I am failing to understand why it has to be a battle between finite and eternal. When I think about simple grade school math class, you can have a finite line with infinite integers between the two points. The more I think about all the theories, multiverse, parallel universe, bubble, or even Krauss saying something can come out of nothing because nothing is unstable, I think of a simple light switch. I think of the "ultimate" "all this" as being that wave function being a fluctuation between the finite states of "on" and "off'. The finite part is "off" that leads to finite "on" and the "forever" is the fluctuation between the two BUT with no comic book human like mythological characters to perpetuate such. .

I didn't understand the part where they said that the decay of the bubbles nucleated as a result of the inflation should look like supermassive black hole from outside. Does outside here mean from our own vantage point or some extra-universal reference frame?

well it's about bloody time! Just kidding - brilliant series that is essential viewing for anyone interested in the subject

The pocket universe stuff around 9:30 is interesting but I'm a bit unclear on some points. 1. What is actually "decaying" to cause the pocket? 2. Is all of the matter produced inside the pocket (e.g. everything in our observable universe) a product of this singular thing decaying? 3. This might be just me misunderstanding the concept, but from the visualizations shown it seems like the decaying portions leading to big bangs / pocket universes are isolated from the expanding "super-universe" that they appear in, yet we can observe our universe expanding. Does this imply the pocket universe produced by the decay itself starts to exponentially expand?

You need more subscribers!

Very cool.

Alan Guth is the man.

Best before the bang.

This shit is so interesting

Is that the music from Kerbal Space Program at the beginning?

These lectures illustrate how abstract components of the Universe work:- in a similar qualitative manner to the way in which a selection of expertise in Building Construction might be assembled and given preliminary instructions on what sort of building is wanted, by pointing out various attributes in existing examples. None of the experts are familiar with the exact attributes asked for, or the particular building examples, so derivative research and coordination is the next stage of the development. Likewise, Inflation +/- is attributable to the Universal rate of change Constant, "e", and closed reciprocal positioning bifurcation, Pi by the inherent Principle in superimposed, "total internal reflection-> dynamical positioning information, "i", as these constants are applied in the connecting-coordinating quantization-modulation systematics of all phenomena. Universal building and construction is continuous creation connection by this e-Pi-i coordination Principle, in this Observable Universe, here-now-forever.

I think about this type of theory every night. It's probably the cause of my insomnia.

Love the Kerbal Space Program music!

It means as the normal arrow of time goes forward to the future the arrow of time also goes back to the past. A novel but strange form of a model for space time.

Excellent documentary, Phil and co, you did well to get together such engaged and engaging speakers with fascinating things to say! Perhaps some links expanding on the topics would be helpful (they would for me since I am writing an article which refers to this video). I note there was the occasional flash of an article, paper or website - links to those would really help. There's also some good supporting information here - www.counterbalance.org/cq-guth/howdo-frame.html - in which Alan Guth explains how inflation works in a widely accessible way. Alexander Vilenkin also has some interesting (and related) things to say here - inference-review.com/article/the-beginning-of-the-universe.

So a vacuum gives rise to quantum fluctuations.When does this give rise to different fields like electric,neutrino,Higgs?In the expansion of space giving rise to this expanding universe,does this expansion weaken these fields?Are these fields only associated with matter or are only detectable through interaction with matter?In the same way as it is said that electrons are a manifestation of the/an electric field,is there a 'vacuum' field that generates the/a phenomenal universe?

With the super telescopes coming on line in the next 10 to 20 years we should be able to see the cosmic event horizon. It would be fantastic if we could see beyond the cosmic event horizon to other stars and galaxies and other universes.

Didn't the discovery of the Higg's Boson at 125.6 Gev convince scientists at Cern that our universe is probably a singular system, as opposed to a multiverse? Didn't the Higg's point to "Super symmetry? Wasn't that the consensus in the Cern discovery on the Netflix documentary?

Part 5 please!

At 32:58, Guth says inflation had a beginning, but that doesn’t mean the universe itself had a beginning.

There seems to be both eternal inflation and eternal deflation of the coordinate systems we use to measure the Universe. I think, this is what everyone is missing when they describe both the multiverse and gravity. There are two distinct types of gravity, the second, lesser-known type is created by the disappearance of the coordinate system beyond the event horizon of black holes. The multiverse is an aberration, and in fact, part of the Universe. Black holes are definitely part of the Universe. The problem arises because no one has yet tacked the problem that in order for any coordinate system to work reasonably, then there must be a flow. We know there is a flow, because there is Time. The base unit of the GUT is the Time Quantum, not any particle.

One question I would have for Dr Alan Guth is: Is Inflation uniform throughout space-time universe? Astronomers seem to measure the inflation of the universe at large scales, which is really a sum or average, but if they could measure at smaller scales, even down to km, would they see a uniform inflation? Could there be small variations when measuring inflation at small scale?

I love the fact that the background music is from the Kerbal Space Program!

The Logical Universe predicts that mono-pole magnetism is inconsistent with the laws of nature and relativity. Although, in mathematical or hypothetical thinking they can exist... Spherical rotation will always create a north and south pole phenomena. This in tern, is relative to plane orientation...

According to Donald Hoffman all physicists are really just learning about our human-specific user interface!! NOT objective reality 😵😵😵 What do YOU think? Yes YOU !

They even got iceman for this one damn

What does the universe expand into?

The hardest part to grasp for me is how can one imagine sizing down billions of galaxies, straight down to a singularity! It must have been one hell of an explosion! Hawking tried to have everyone understand how chaotic this process must have been, let it's probability! Wow!

5:32 anyone else wondered why he writes with so much space between the words? ;)

This is very interesting. One question that this bring to my mind is, if our bubble universe is finite space, even if we cannot see from here that far, what are the properties of the edge of our bubble universe?

awesome

Inflation; When the Dielectric Energy decayed from the Inertial Plane in Counterspace. Absolute Zero, 0K, is in the Inertial Plane, Counterspace. That's why Space is 2.43K. The smaller the Spacial Footprint, the higher the Capacitance. The higher the gauss, the smaller it's field. Scalable Aether, Casimir Effect Universe! Space and Counterspace are the plates, the Inertial Plane attracts and repels the plates. Grand Expand/Big Bang; Dielectric energy decayed into the Dielectric Voidance Field/Magnetism. Magnetism gives Magnitude to the Universe. BANG!!?

Alan Guth rules

But gets me feeling queasy in the stomach, is what happened before all of this... and before all of before all of this so on and so on...

Physicists too play KSP, confirmed.

Always enjoy seeing Alan Guth talk about inflation, and this presented a relatively comprehensive explanation of the relevant issues, especially given that it's only an hour long. I'd love to ask Sean Carroll about his notions regarding the model he's working on with Guth (presumably an extrapolation on the Carroll-Chen model); he takes the Everett many worlds interpretation o quantum mechanics as the most likely to be accurate (as do I), but he discussed ideas regarding what he called 'mad dog Everettianism' in another talk. In that talk, he said that quantum fluctuations in a De Sitter space don't happen, given certain sensible assumptions about degrees of freedom, because the Schroedinger Equation is static, and there are no interactions, and hence no quantum decoherence. It's one of the rare instances where an interpretation of QM actually has a different outcome from other interpretations, though it is (ironically) a difference that we couldn't possibly test or observe in any way. In the Carroll-Chen model, as far as I recall, the assumption was that a sort of 'thermodynamic middle' to the multiverse occurred in a background De Sitter space. If there are no quantum fluctuations in a De Sitter space, and it's describable by a quantum wave function that never collapses, how can that space yield inflationary events? In any event, he has very interesting ideas regarding the arrow of time. If y'all ever do a follow up video, I'd love to know how he reconciles his conception of 'mad dog Everettianism' with the Carroll-Chen model and/or the model he and Guth have been working on. It's a fairly natural extension of the question of how a system that's naively at maximum entropy can have further increases in entropy. If y'all ever end up at Cal-Tech, it might make for an interesting documentary either way.

Universe may be expanding and colliding,and in this moment we are seeing only expanding part,,may be possible

Good stuff, but please buy a better microphone when interviewing Guth.

If we see positive curvature, it does not necessarily invalidate bubble universe - we may be living on the surface of the bubble.

If everything was packed to a such high density at the beginning of Big Bang does not that mean that all the particles in the universe also was being entangled with each other at that time and still are? Providing that they all was being entangled at the beginning of Big Bang could the mean that this resulted in the creation of space it self?

Does inflation and expansion of universe mean same. My doubt is where is universe expanding ? I mean into what ? Where it is acquiring space from ?

Please activate subtitles

In Alan I believe

obiously the universe had infinitely expanded of inflation until it got to the point when the big bang happend and scientist said that our universe is still expanding.does that mean that the empty space outside of our universe being covered by. and does that mean if our universe going to grow and if there is another growing universe like ours will it bind with ours and form a bigger universe call a double.and will all the universes bind together form a universe system?

Contemporary cosmology has outgrown the word 'universe'. I have always defined this word to mean: EVERYTHING... absolutely everything, no exceptions. If this is true, the term 'multiverse' is absurd. Alternate terms like 'bubble universe' or 'pocket universe' only compound the confusion. Penrose is careful to call the period from the big bang to now an 'epoch' because he envisions an endless chain of 'epoch' segments comprising the universe.

There seems to be something magical about the number two... Where are all the threes in physics?? Just twos for area, and everything that comes in binary pairs.

Dark energy is an illusion caused by the gravitational distortion caused by the gravitational fields of distant galaxies. Gravity from distant galaxies has a redshift effect on the frequency of light they emit in the same way that gravity can bend the path of light. Hence no cosmic acceleration, no dark energy, no un accounted for dark matter, no big bang, this universe is eternal, no beginning or ending. Cosmic background microwaves are just distant galaxies who's light has been gravitationally distorted beyond your visible spectrum. Galaxies exchange and recycle energy and birth new stars out of old dead ones.

Add subtitles please

If we can prove, that the observable universe is not collapsing to itself we can conclude, that there is more materia than exploded in the BB, as BB was an explosion etc. didn't appear from nothing, but all the materia in it like all there is has always existed. Imagine a process from nothing to anything, doesn't happen, so infinite time in the past also thus if not collapsing, has to be more materia than exploded in the BB.

why do i think of kerbal space program when watching the first minute?

Guth seems to contradict himself when he states that it is difficult for something to be eternal, but only for some of the time. He later references a paper from 2001 where inflation had a specific "start". Nomura talks about his 2012 paper @t "where the multiverse does not have a beginning or end."

Whys it playing KSP music?

Basically John Milton!

Great Hypothesis...that's all.

I´m a Christian, and, I know you kind of are not ;) but, love your work. I´m sharing it on my facebook managed page. All 4 of them, if you don´t mind.

If there are an infinite number of ways that the entropy of inflationary perturbations (uniform mass of matter and energy that existed milliseconds after the big bang) can be different and an infinite number of e folds of the slow roll inflation can be different, if there is an infinite number of ways that the value of entropy at the big bang and value of mass at the big bang can be different, If there are an infinite number of ways the average density of normal matter can be different, If there are an infinite number of ways the density of dark matter can be different, If there are an infinite number of ways that the density of dark energy can be different, If there are an infinite number of ways that the cosmological constant can be different, if there are an infinite number of ways that the ratio of dark energy to dark matter to normal matter can be different, if there are an infinite number of ways that the value of entropy and density at the big bang can be different, If there are an infinite number of ways that the laws of physics can be different, If there are an infinite number of ways that the constants of nature are different, If there are an infinite number of ways that the string theory vucua can de different, If there are an infinite number of ways that the string theory geometry can different and finally if there is an infinite number of ways in which the strength of the inflationary field in which new universes are created are different then how is it possible that our exact lives are being relived right now in another bubble somewhere else in the inflationary multiverse and how is it also possible that the exact history of our bubble universe be repeated in another bubble universe of the inflationary multiverse.

Disabling the closed caption prevents a whole bunch of people from watching it.

I think this video is decent, but is missing recent results, that really call inflation, particularly, eternal inflation that generates a multiverse into more doubt, which I wish the authors of this video would include: 1. Gratton and Turok: arxiv.org/abs/hep-th/0503063 2. Kohli and Haslam - arxiv.org/abs/1408.2249 - Shows that a multiverse generated via the common picture of eternal inflation is not mathematically viable and leads to strong singularities. 3. Kohli and Haslam - arxiv.org/abs/1508.02670 - Shows that for a generic inflation scenario to generate a multiverse requires a high degree of fine-tuning, particularly in the initial anisotropy, geometry, and of course, initial conditions.

3:40 "so large and emerged so quickly" we know this from inflation or something else?

Is the smooth exit from eternal inflation of hawking's last paper disprove eternal inflation