Mindscape 115 | Netta Engelhardt on Black Hole Information, Wormholes, and Quantum Gravity

Stephen Hawking made a number of memorable contributions to physics, but perhaps his greatest was a puzzle: what happens to information that falls into a black hole? The question sits squarely at the overlap of quantum mechanics and gravitation, an area in which direct experimental input is hard to come by, so a great number of leading theoretical physicists have been thinking about it for decades. Now there is a possibility that physicists might have made some progress, by showing how subtle effects relate the radiation leaving a black hole to what’s going on inside. Netta Engelhardt is one of the contributors to these recent advances, and together we go through the black hole information puzzle, why wormholes might be important to the story, and what it all might teach us about quantum gravity.
Netta Engelhardt received her Ph.D. in physics from the University of California, Santa Barbara. She is currently on the faculty in the physics department at MIT. She recently shared the New Horizons in Physics Prize with Ahmed Almheiri, Henry Maxfield, and Geoff Penington, “for calculating the quantum information content of a black hole and its radiation.”
Blog post with audio player, show notes, and transcript: www.preposterousuniverse.com/...
Patreon: / seanmcarroll
Mindscape Podcast playlist: • Mindscape Podcast
#podcast #ideas #science #philosophy #culture

[@Longevity-gu1ut]

Netta's passion is palpable - excellent episode. Sean is an excellent interviewer as always

[@l33thaxor33]

She is amazing

[@no1nos]

Sean - just wanted to let you know that adding the title & picture to the thumbnail has helped me in the last month to remember which ones I have listened to or not. Overall its helped me to identify new episodes more consistently. Thanks for making the change.

[@readingRoom100]

so, was "no1knows" taken or did you prefer the symmetry, lol

[@OrlOnEarth]

@@readingRoom100 can't say the same for you lol

[@HarryNicNicholas]

@@OrlOnEarth felicitus est parvus felinus calidas

[@HarryNicNicholas]

@@readingRoom100 or is it No1 Nose?

[@Grinsekatze113]

Thank you for not starting at the basics. its hard to find content on science that is more advanced without being dry.

[@chucks2k]

Thanks Sean for the opportunity to listen to a pair of exceptional theoretical physicists discuss an outer edge of physics thought. One of my favorite.

[@RKarmaKill]

Dr. Carroll . Please respect the man

[@user-gm5xx8wr6m]

Oh, this is one of the best episodes, with the biggest topics all together.

[@RooBot]

Couldn't agree more!

[@naimulhaq9626]

Very valuable talk. I am surprised how Susskind could predict conservation of information, before Maldacena's ADS-CFT correspondence or the gravitational path integral. Interesting.

[@codyramseur]

Thank you! This episode dropped when I’m just becoming able to fully digest these concepts and I’m also very passionate about learning about them.

[@sebastianclarke2441]

Oh wow I'm gonna have to give this another listen or two ....the last 10 mins in particular. This is about as abstract as ideas get, thanks for an utterly riveting conversation!

[@BHPhreakyx]

Stunning episode Sean!, Fantastic content from you over this pandemic. Can not thank you enough.

[@colbynye5995]

Another great pod cast! Thank you!

[@fugslayernominee1397]

This was an amazing episode. Got to learn a lot toady. Thanks for sharing or making it available for everyone.

[@EldafoMadrengo397]

This was the best episodes so far. Fascinating and inspiring!

[@visualight2010]

This is best one - perfect pacing and great guest dynamic - many times have I listened to this one! It unfolds beautifully 😊

[@martinds4895]

Great episode, I love Mindscape. Thanks Sean!

[@PugetSoundFlyer]

Fantastic Episode! Thanks Netta and Sean.

[@bechupandit2882]

Keep up ur podcast. I love them.

[@owaisahmad7841]

All Sean Carroll's podcasts are excellent. All of his, guests like Netta Engelhardt are such great scientists. Delightful stuff.

[@codemech99]

Great topic! Please keep it up.

[@Ometecuhtli]

Interesting talk, very challenging to think the outside structure of a black hole could hold the gravitational information, makes me wish I could follow the steps to the conclusion as reaching it must be one very pleasurable intellectual exercise.

[@timenixe]

Really interesting. Thank you

[@tiadiad]

Flew by so fast. Amazing episode!

[@johnimusic12]

Try playing it at 2x speed haha.

[@lukemurray-smith5454]

Amazing discussion, thank you so much!!

[@grahamhenry9368]

Netta is super intelligent, and very interesting to listen to. Looking forward to hearing more from her in the future

[@HyperFocusMarshmallow]

The best one yet!!!

[@isedairi]

Sean, you should have asked her to talk about her opinions on Firewalls, Fuzzballs, and ER=EPR developments (this last one she spoke about a bit). Either way, somebody should write a nice popular book on all of this (Lenny's book needs to be updated)

[@bentationfunkiloglio]

Magnificent discussion

[@user-xl7zv2gm7w]

If photons move through space at the speed of light and move through time instantaneously from its reference frame. "Normal" Matter moves through time at the speed of light could dark matter be something that moves through time at some other speed than the speed of light and would that be why it does not interact with "normal" matter except through gravity?

[@dannyboi404]

Looove this topic so much! Wish this conversation could continue for another couple hours. Not sure if it's directly mentioned, but does this support/refute the work being done by Susskind and others, or are the ideas mutually compatible? Also, a definition of AdS, how much it differs from our universe, and why it's even a useful model at all would add a lot. Seems to get glossed over many of these conversations. Thanks for the amazing convo.

[@amityaffliction4848]

AntideSitter space is a space-time framework in which the energy of space-time has a negative value as opposed to a positive. Personally, I think it’s useful because it shows that gravity can be combined in a quantum mechanical framework even if AdS is not our spacetime

[@zdlax]

The fact that, unlike common objects, event horizon radii scale linearly with black hole mass is fascinating and it makes the holographic stuff much more intuitive and believable.

[@BrynSCat]

If a field can be treated as a geodesic.(PE “ERER” bridge). Two interconnected P.E. wormholes.(Twisted Alice Universe) Thus the shape of the Universe is defined by its contents ,a Positively Closed Universe. Cosmological red shift can be interpreted as time dilation due to distance & not velocity. No need for Dark Energy,No matter-antimatter asymmetry,No Time asymmetry problem.

[@bruceneeley1724]

Great episode...

[@purplepimple2610]

Great shows. Great sound. Just great all around.

[@ajosin]

Good stuff 👍 My question: Could we use entangled photons through LIGO to check for quantum gravity effects (would entangled photons interact more gravitationally with themselves since they are not really that separate in a hypothetical fundamental QM entanglement emergent space)? Alternative put entangled QM states in trough a very precise gravity torsion measurement. Thanks!

[@ikitclaw7146]

Ooh i like the question, would there be any difference at all using entangle photons? really hope you get an answer.

[@alexwilson8034]

Keep making these videos please!!

[@PavlosPapageorgiou]

40:05 Does the duality stop there? Is there exactly one correspondence between ADS 3+1 dimensions with gravity and CFT 2+1 without gravity or are there yet more equivalent theories to be discovered? Is one of them right or are they really equivalent ways to describe the math of something abstract that goes on and one of them is just closer to the kinds of structures that we are?

[@smoogems]

Thanks Carol. You the best.

[@nathanialblower9216]

1) What’s the point of the book example? To confuse people by bringing in an irrelevant sense of ‘information’? Or is physics going to put the book back together and then read it to you? Will it translate it for you too? 2) This guest was easily in the top 5 of the guests you’ve had on. Great episode!!

[@PavlosPapageorgiou]

11:46 When you make a measurement information is not lost, it is created. You get a new bit describing the outcome. In Many Worlds, this bit comes from self locating in one branch of the wave function. In spontaneous collapse a bit really is created. And in classical determinism all you ever do is probe lower order bits from the initial conditions.

[@StephenPaulKing]

The thing is that if we treat Information as a conserved quantity then it can neither be created nor destroyed, so.... Be careful.

[@PavlosPapageorgiou]

@@StephenPaulKing I agree. In Many Worlds the information is globally conserved and is whatever defined the initial state of the universe. The entanglement and decoherence process creates bits of information that tell you which branch of the wave function you're on, but obviously the other branch has the opposite bit. One day I'll write a paper re-casting the 2nd law as a consequence of information conservation ;)

[@sambarta9865]

Missed the physics content, and hearing Sean's voice

[@RichardTScott-me2rm]

sorry to ask bwhat does

[@sambarta9865]

@@RichardTScott-me2rm love heart ❤

[@RichardTScott-me2rm]

@@sambarta9865 i could not have guessed that thabks

[@sambarta9865]

@@RichardTScott-me2rm haha all good I should have just used the emoji

[@nurk_barry]

As long as no observer could ever see the information both inside the black hole and outside smeared onto the surface, causality should be safe according to general relativity. The dual-description of a 2d boundary (area) and the interior is what the holographic principal is all about. Love this subject!

[@robertglass5678]

I love the holographic universe idea. I mean, I don't really understand it--but the idea that reality is really a lower dimension surface is far more mind bending than even the Many Worlds Interpretation of Quantum Mechanics.

[@timdixon3410]

As a black hole evaporates, it should reach a point where it is not dense enough to be a black hole anymore, there is where the information stored in the singularity could be released back into the universe.

[@enlongchiou]

Black wormhole l=gm/c^2=(hg/(2*3.14*c^3))^0.5 deduce quantum gravity ch=2^3.14*g*m^2=(2*A*137*pm*c^2)*(4*3.14*A*137)=13.6*e/10973731 EM force.

[@JP13795]

Wat

[@LuciFeric137]

Excellent

[@bombayfoukiki486]

U should Film those podcast !!! IMO

[@wmpx34]

He’s in his skivvies

[@isonlynameleft]

Great video! Still not sure how this solves the paradox though.

[@AbhishekMahajan]

Thank you so much #SeanCarroll and #NettaEngelhardt

[@conormacnessa7723]

Please Sean can you address the Electric Universe model as distinct to philosophical science. Plank, kirchoff and black body radiation; the temperature of sun Ray's as distinct from the temperature of the sun. Is dark matter a black body. If black holes evaporate are they radiating as a black body? Given "gravity" holds the universe together, then where's the electric component of this catered for in philosophical science. In the rule of thumb law in electricity, the E, M, H fields generated by a flow of electricity down a wire are generated. Consequently in cosmological terms where are these components expressed? How do they correlate to each other. How can gravity be a separate function, given everything is connected?

[@StephenPaulKing]

How about the exploration of tidal effects just out side the event horizon itself?

[@ArtVandelayLTEX]

There are some seriously intelligent people in this world.

[@nickknowles8402]

Brilliant

[@JustOneAsbesto]

I'm glad you're having fun doing these, Sean. We're having fun too.

[@samantha5357]

Fantastic

[@cryptolicious3738]

sean, the information isnt lost, the simulation just throttles changes to zero for BHs. works great for saving cpu from wastefully calculating too much in too small a region.

[@PavlosPapageorgiou]

34:00 To ask an even simpler question how does the gravity of a black hole get out of the black hole? If we assume the mass is at a point in the center, how do gravitational waves get out to signal what the mass is doing? Are we forced to conclude there's no interior and the entire phenomenon happens at the horizon, or the singularity and the horizon are somehow the same thing,? Some maximally entangled and most compact state of space perhaps.

[@ajosin]

Maybe the holographic principle helps here? The quantum field theory at the surface of the black hole (and changes at that surface) are equivalent to the inside of the black hole.

[@PavlosPapageorgiou]

@@ajosin Thanks, I heard Susskind's explanation. The holographic principle is a hint that if a back hole can be modelled as a hologram at the horizon then maybe any phenomenon could be modelled as a hologram on a surface, any surface big enough to enclose the phenomenon. It might just be very hard to calculate on that surface because points become spread out waves like in a Fourier transform. Personally I suspect the horizon is an actual limit where you see the pixels of the hologram so to speak and there's no inside, but it could be that spacetime warps so that the horizon looks like a single point to someone falling in and being smeared around it.

[@quill444]

This would be my guess: What we call "gravity" is actually a distortion of the equilibrium of an already-existing, omnipresent space-time field that is present throughout the known universe, while light is the stimulated emission of a source of localized, electro-magnetic energy. Therefore, the existence of a black hole would be able to distort the field and alter the effect that we call "gravity" but would also simultaneously inhibit the ability of any localized light to travel in any 'direction' other than 'inward' and thus prevent it from being able to escape. - j q t -

[@wholelottared6166]

everything that i love

[@krisniemczuk3452]

Sean, is it possible, in your opinion, that the edge of our unierse is an Event Horizon, which would mean that we live in a giant black hole?

[@mkc1rrc]

I like the fact that entanglement is a universal principle that encompasses the fabric of space and time - I guess the hippies were right...'all is one'. All we need now is a wormhole generator and we can truly go where no man has gone before....or even thought about going before.

[@JAYMOAP]

She is great 👍

[@jainalabdin4923]

My hypothesis: Hawking Radiation leaving the evaporating black hole is still entangled with its paired radiation that entered it. This radiation, after entering the black hole, exits into another part of the universe through a connected white hole, and combining these pairs of entangled radiation recovers the Information Paradox.

[@pizzacrusher4632]

This really appeals to me. is the white hole in the same universe (or world?) and the one with the black hole?

[@pizzacrusher4632]

Usually my problem is that all my "insightful thoughts and questions" turn out to be things that highly annoying people have been asking for 70 years now and have been proven silly the entire time... /sigh...

[@jainalabdin4923]

@@pizzacrusher4632 If you define the 'universe' as being the observable and non-observable universe, then both the black hole and white hole could be anywhere, connected like a wormhole, and also be spanning infinite spacetime.

[@JAYMOAP]

Not really.

[@kapsi]

What happens to electric charge, if all that gets out of a BH is uncharged photons? Is this part of the lost information?

[@alexandermartins65]

Shouldn't we call gravity an effect rather than a force. Ex: the mass of a planet/star bends spacetime and its effect is gravity. The strength of the effect is relative to the mass. Or am i missing something.

[@deeprecce9852]

Still listening but already got so many questions 😂😂. What symmetry relates to conservation of information? If the fastest speed is C, then we can never catch up with information departing at C, isnt that lost information?

[@banehog]

It's not lost because *you* can't reach it - it's lost if it no longer exists in the universe.

[@kevconn441]

Conservation of information comes from the second law of thermodynamics. Entopy, and the information that describes it, always increases. (or is it the other way around?.)

[@mightyNosewings]

It doesn't seem like you can get conservation of information from a symmetry, at least not in the context of Noether's theorem. Conservation of information is exactly the same as saying that the action of a dynamical system is an isomorphism of its phase space. This is a sort of symmetry, but at a "higher level" then what Noether's theorem talks about.

[@deeprecce9852]

@@mightyNosewings thanks for the reply..so how critical is this conservation law, to physics, as in like for example if conservation of energy is violated it will messed up science.. Is conservation of information also as critical?

[@kevconn441]

@@mightyNosewings Each state in the phase space is an energy state. Entropy increases as the energy density distribution increases, and the other way around. Entropy is information about available quantum microstates. Conservation of information is the quantum equivalent of classical conservation of energy and both come from time symmetry thanks to Noether.

[@The1Helleri]

Could all black holes everywhere be collectively pulling on space causing it's expansion? That expansion in turn being fueled by information in the black holes? Like maybe space is just one big white hole? There more black holes that get bigger as time goes on right? And the rate of the expansion of space appears to be speeding up? Seems like those two things could be inexorably linked to me.

[@JP13795]

As soon as I read black hole, wormholes or quantum gravity, I get sucked in and click on it right away.

[@waylayin6159]

If there are two entanlged particles and you shoot one into a black hole and then measure the other. Would that be getting information out of a black hole? Or do they become untangled?

[@adraedin]

Asking questions is a great way to stretch your mind! Inferring some information about a particle that went into a blackhole via a particle that stayed outside of it isn't really extracting the information "from" the black hole, per se. The analogy I often use for entanglement is: two particles that just collided and headed off in different directions (akin to light rays off of a mirror) - by measuring one particle's path, you can in infer the other and vice versa. Unfortunately, it gets more complicated the more "stuff" you add to the collection of interactions. If you add a third particle, the other two become less entangled with themselves and more with the new, third particle. Add a fourth, fifth, etc. and the entanglement essentially gets diluted & deteriorates, this is called "decoupling". So, yes, the particle you shot into the black hole would become "untangled". I'd encourage you to check out the PBS Space Time channel - it has quite a collection of videos on these types of subjects with nice visuals to aid viewers in wrapping their heads around these complex topics.

[@diegogomez7240]

Dr. Drew sent me here. Keep em high and tight mommies

[@PavlosPapageorgiou]

17:10 Why do we give credence to General Relativity saying black holes are completely smooth so to speak? Clearly GR is a classical approximation and doesn't have a model of microscopic processes.

[@Achrononmaster]

It is because they are talking about large black holes, from collapsed stars. The enormous gravitational fields squash density fluctuations, smoothing out the roughest surface, same as on a neutron star (very smooth). This holds regardless of quantum fluctuations which fuzz-up the surface. The quantum fuzz is tiny, sub-molecular, so black holes even quantum mechanically will be the smoothest things around. Even more so since once the collapse occurs the "surface" is virtual, and you can't get smoother than that.

[@KaliFissure]

Great series of shows! 👍 Even if i have a totally different take on the topology of or universe. Neutron decay cosmology. Neutrons which contact event horizon become the vacuum energy for a single Planck second then re-emerge in lowest density points of space. Deep voids. And decay into amorphous atomic hydrogen. Solving information paradox (Hamiltonian is local and is retained), fine tuning, dark energy/expansion/Lambda. And the decay product is dark matter. Seems too simple but the nature of neutrons and the fact that they decay into hydrogen atoms is the key. Our manifold... Sin(cos(u/2)cos(v/2),cos(u/2)sin(v/2),sin(u)/2) 0

[@paxdriver]

Why can't space-dimensional matter be converted into a time dimension stream? We can stream 2d raster into video and vr 3d renders, or use textures to deform 3d meshes, or imaging sound with oscillator graphs... all as functions of time, intrinsically; Q: why can't information be getting compressed [x, y, z] into an infinitely elongated t axis - like would be as a black hole singularity. Matter should be able to be compacted entirely along a time dimension if it is truly a dimension of space-time, putting it out of our reach but yet its information/energy still being conserved relatively from inside of itself.

[@MNbenMN]

Not sure I follow all ypur thinking, bit it made me think some stuff, too. :) In the first part it sounds like you are taking about mapping between discrete 1d, 2d and 3d models of pixelated or sampled information, which I think should be considered as different from quantized information distributed in continuous spaces. Someone like Sean would be able to address that better than me! And, with computer graphics projecting textures onto surfaces of 3d models is just going from flat 2d to non-flat 2d, and were really just taking about making 2d feel like 3d, it's not substantively true spatial 3d, even with stereoscopic 3d glasses or vr goggles, just a convincing optical illusion. In the second part: If you are talking about information in a black hole pushing out onto the t dimension infinitely as a solution to the information loss paradox, that seems like it might work if black holes exist forever. But, I don't know that infinite spatial curvature even changes the radius intrinsically within the event horizon or not; that's beyond me, but I thpught it was more about the radius becoming timelike, not infinite. Nevertheless, the paradox is because black holes evaporate. I don't know but maybe that means there is only a finite range of t available in a black hole? It seems like you still have a bunch of information going into a region before the evaporation, and no information left after the evaporation. Otherwise, if you are talking about how the radius of a black hole becomes timelike inside the event horizon in general, my firsy impression is that 1d is not enough to represent all the information since there is still the relation that the maximum information that can be contained in a 3d region is proportional to the 2d surface area bounding a region. This makes me wonder, though: If all the information in a spherical volume can be encoded on the surface of that sphere, can all the information in a circular disc be encoded on its edge? If so, is there some 1-dimensional manifold that can encode all the information from the surface of a sphere, and would the length of that 1d encoder be longer than the diameter of the sphere?

[@paxdriver]

@@MNbenMN lol I don't know either! It just made me think. With respect to 2d textures affecting 3d mesh models, I wasn't meaning to imply any illusions, I meant literally applying a texture map as a displacement vector for a mesh modifier (in blender terms). Similarly in blender slices of textures can be used (like noise or voronoi) as fill data to represent a true 3d volume within the bounds of a mesh without ever adding more detail than the texture map itself. But on that same vein, I CAN however add rgba data to my 2d map to add even further detail and resolution. In this analogy color is a data dimension beyond the limits of x and y, but as far as the texture map is concerned that rgba data can be embedded within it and viewed and measured by an engineer in flatland if the flatlander has spectroscopy tech lol. It's interesting and thought provoking how you mentioned the evaporation of the black hole because as my mind tries to grapple with concepts like infinities, I can't help but consider that the slowed t inside the black hole must not experience its own evaporation; and since we can see and measure it even though an observer inside the black hole couldn't, would the information even be lost if it still exists for someone else depending on their location relative to the event horizon? How can something age if it swallows the fabric of time itself at its tiny core? I'm not sure I agree with the holographic hypothesis, I think we could read or discover information from that disc but it is not the infinitesimal point of interest so that area can be weird and in constant flux without any conflict (in my novice and hobbyist "understanding" lol) since whatever we perceive and measure is itself inherently subject to the flux of material reality crashing and spinning all around it. It wouldn't surprise me if our measurements were wrong since all equipment and electronics are oscillations themselves, and minute changes are prone to exaggerated repercussions when spanning space to reach our instruments. It's just mind bending, I love it lol thank you for the food for thought, you've got me going again lol

[@NightmareCourtPictures]

You have the right idea. Holography and projection as it is in a video game are the same thing, and I’ve went and tested these notions myself. I’ve actually gone through the proverbial rabbit hole 5 years ago to figure out why, and to cut to the chase and keep it short: dimensions are arbitrary equivalent constructs. 0d = 1d = 2d = 3d and so on. Consider that your computer is just abstractly 0d data points that are read in 1d sequence, to create 2d images that then form a 3d game world, and converted back into 2d for us to see. The notion that dimensions are equivalent and arbitrary constructions leads to the point that the universe is constructed like a computer would; from 0 dimensional information…and this is where things like ADSCFT and Hologram Theory get it wrong in that rather than a 0d point like construction, they claim the infinite 2d sheet exists outside the universe (tin can universe) which leads to the same obvious problems like lack of observable because the sheet has to be infinitely far away and infinitely large. The other thing is that there is a relationship to the observer involved in this too. You can imagine algorithms like ray tracing which work off of a similar idea… that the screen in some sense can present to you real world graphics, but it requires information that is hidden from us typically. Ray tracing constructs this information by shooting rays and collecting the number of times those rays bounce before returning to the screen. But to put it another way your eyes do the same procedure: they look out into the world and photons come in and hit them. Those photons had all the information you need to construct the image of the world you currently see…but much of that information is not accessible to you because you only received the final part of it…that photon was over here then it went over there and bumped into this thing and did a million other things changing energy levels and what not before getting to your eye at that final energy level and thus all that information of where it went exists in that photon but it’s been squished into its final state. This squishing is called coarse graining and it’s an important reason as to why there’s so many observer based issues with physics modeling…information is omitted and then we wonder why the equations don’t work to perfect accuracy. So that’s just the beginning of the extremely deep rabbit hole…in the end of the rabbit hole the only theory that actually addresses these things is the wolfram physics model. If your interested I’d suggest two things : 1) go and watch the lecture “how universal is the concept of numbers” and then after that watch the book series “New Kind of Science.” Wolframs idea is that the universe is this 0d computational structure that can be modeled as a network, and that this computational structure is of the size of a true Turing machine statespace and the observer dependence we see is what gives us the physics we have created to describe this infinitely complex object. Because of its infinite complexity and our finite size we can only perceive it through coarse graining it…thus like states in the video black hole information paradox is that information is lost when trying to describe or perceive it but not destroyed…the surface of the black hole is like a 2d image of a 3d world and that image contains the information of that world but the information is hidden from us in the same way.

[@brianstevens3858]

14:23 Dichotomy presented, maybe false, Information, thinking other, Maybe it's being converted to something we don't have conception of yet.

[@brianstevens3858]

@@jengleheimerschmitt7941 Fair point, I would point out though that given, "In physics, a conservation law states that a particular measurable property of an isolated physical system does not change as the system evolves over time." Key word being isolated.

[@naimulhaq9626]

There is a reason why Maldacena conjectured that the whole universe (Hawking's single wave function) is a QC function, if only we could know the algorithm (which we may never know) which ensures 'determinism', leading to evolution of life, soul and consciousness.

[@Theking0fgg]

There is no "throwing a book into a black hole" There is only getting sucked in with the book.

[@MNbenMN]

Are you claiming black holes suck?!

[@Theking0fgg]

@@MNbenMN No, no I am not

[@debbiejohnson1166]

Hi Sean! Great channel! Its awesome leaning about physics and such interesting facts. Wondering something. Would you by chance have a sister named Samantha? 🤔🌌👍

[@adraedin]

He does not have a sister named Samantha.

[@enterprisesoftwarearchitect]

“Space time is not fundamental” … by definition there is no change nor flow without time. Right!?

[@websurfer352]

If?? If virtual particles originate from separate universes, the positron from the twin mirror-universe then the information pertaining to this universe remains the same radiated off as Hawking Radiation?? If the hypothesis is correct that the virtual positrons originate from the mirror-time-reversed twin universe to ours the Information would not be conserved if the virtual positron survived?? Then the positron would constitute an anomalous bit of information!!

[@eugenebunt5515]

Einstein gave us the answer to gravity, warped space/time. And he told where to look for it, the bending of light in a gravitational field. On May 19, 1919 astronomer Arthur Eddington took a photograph of a constellation that lined up behind the Sun during a solar eclipse, and it confirmed Einstein's prediction of light bending in a gravitational field. The background star images moved away from the Sun, as if you were viewing the constellation through a huge positive lens. Einstein described the mechanics of this observation by imagining a series of elevators rising from the Sun’s surface; light enters the elevator at a higher level on the far side, and then it exits at a lower level on the side closest to us. As light traverses elevator after elevator, its path bends so that the star’s images appear to be at a greater angle away from the Sun (“The Evolution of Physics” © 1938 by Albert Einstein and Leopold Infeld page 220.) Mass slows time which alters the distance matter can travel in comparison to less mass areas. Elements can be identified by the light they radiate due to the unique number and position of electrons in their electron energy-shell levels where photons are absorbed and emitted, resulting in dark spectral lines distinguishing each element. Using these spectral lines as light-wave-length markers; light-waves red-shift for each element when coming from a massive star, this means that light from specific elements travels farther in comparable length when coming from the slower time-rhythm with fewer seconds compared to the surroundings of a massive star. The fabric of space stretches as illustrated in gravitational embedding diagrams toward the center of mass allowing light and matter to move farther/faster using less energy toward the comparatively slower time-rhythm. To imagine the space-time warp allowing objects to move farther in the same amount of time while coming from a massive object with a slower time-rhythm: think of an object moving directly away from you, the light waves coming from it will Doppler shift, the waves will be less frequent in arrival, but you will have witnessed the object move farther by your standard of light speed for the same amount of time. If you think of a second as the time it takes for light to travel a certain distance, that is now time plus greater distance. Sir Issac Newton said you move through space freely without friction, Gravity is the result of moving farther/faster through the rising elevators toward the slower time-rhythm and then being stopped by the planet surface, change in momentum lags change in velocity, which feels like deceleration/gravity. Gravity is the kinetic energy of momentum. Gravity is simply a change in uniform motion.

[@steventokeshi8847]

The universe of misplaced keys and sunglasses

[@FartMustard]

I don't like the table analogy. all you really have to say is that the universe is the table and whatever is larger than the universe that we don't understand, that is where the information would go. We just don't have the ability to look beyond the table

[@quill444]

If our own Sun were a Black Hole, what would it look like from Earth when a Star such as Sirius passed "behind" the Black Hole? Would the light from the star begin to distort or bend or would it begin to diminish in intensity (or would it appear to do both) and at what rate and for how long? What geometric "shape" (if any) would the 'shadow' cast by a Black Hole produce? - j q t -

[@stringologymchugh4245]

I think our universe is inside a black hole and the black holes we observe are a way out of our situation.

[@ajosin]

Interesting. If so, would the bing bang be a big bounce right after the matter forming the black hole collapses to a point?

[@David-tp7sr]

I've often wondered about these mathematical "tricks" we do in physics and how real they actually are. These fake Euclidian spaces where the wormholes take place that Netta and Sean are describing seem to be another one of them. The "unreasonable effectiveness of mathematics" should give us confidence that, yes, we should just accept it and follow down this path. My popular level of QM fandom has left me quite a bit in the dark with this episode and I am thankful to Sean for pushing the limits.

[@alasdairwhyte6616]

information must be lost; how do you recognise any particular particle? information in a book or human construct must be lost - again how do you recognise any particular particle that the construct is broken into? information is a human construct

[@ikitclaw7146]

information in a book is somewhat different to the information of particles. in the same way the time on your ticking clock has little to do with time as a force or dimension. Each particle has its own innate "information" its not some list of instructions written in small print, its another kind of information.

[@S.G.Wallner]

Anyone else thinking... But what is the information we are discussing here?

[@gerrywilliams1151]

I am so spoiled.. I need video.

[@Amethyst_Friend]

DYNAMITE!

[@shirsenduchatterjee5042]

Sir I have an idea of how the time started, something more than big bang theory, by using one electron theory and multiverse theory, and string theory, I think it can also explain the dark energy, can you please check this, but I don't know how to send it to you.

[@darkstar2111]

So it's time to make a hypothesis out of your idea, create a way to falisify that and publish it as an scientific article. Good luck!

[@RooBot]

@@darkstar2111 - Don't forget peer review :)

[@dankuchar6821]

Just publish your idea with the supporting observational evidence and the discriptive mathematical framework.

[@shirsenduchatterjee5042]

@@dankuchar6821 that's why I need Sean M Carroll's help, I can explain it with the help of space time diagram, but no math that I know can ever go through the beginning of time .

[@darkstar2111]

@@RooBot Peer review is done by magazine/journal you are applying for publishing :) (good ones at least)

[@jhdytube]

The explanation for why information loss is bad was very unclear. Basically it was ”I don’t like it”.

[@walterzagieboylo6802]

Where is the blackboard?

[@laroark5036]

On the wall

[@dadaimiza]

😍🙏

[@briantep458]

Richard Feynman and strip clubs, man you learn something new everyday

[@PavlosPapageorgiou]

1:08:30 Path integrals, dualities, and Many Worlds don't get the attention they deserve. They're clues that the universe works not one way but all the ways that are consistent with some mathematical constraints. Any linear evolution that you see emerges from large scale consistency of those constraints and looks radically different depending where you are. It be interesting to hear how David Deutch presents this concept in Constructor Theory.

[@KaliFissure]

There is no way any sort of ensemble is going to traverse a worm hole. There are no white holes. This is an error of understanding in topology. Black hole is a gathering. The opposite is a distribution. Not a single point showing out but a totally distributed energy. The opposite of a locality is alocality. The other side of Einstein Rosen bridge is the entire energy surface of universe. This is why the neutrons which infall to a singular location are redistributed according to lowest energy POINTS of universe. One here. One there. Distributed.

[@markw6008]

Love this podcast but the audio lately makes it almost unlistenable. I miss the days of having the guests in studio.

[@lizbmusic11]

Wow. I am no physicist but I absolutely love your show and these huge topics. Science is attempting to demystify the workings of God. Will we ever know everything?

[@chirosaen1656]

Thunderbolts.info

[@greenmonsterswat4425]

Buy a microphone Netta! Please!

[@michelmulder5770]

Yeah a female theoretical physicist!! Refreshing

[@AdiMaco]

If a black hole radiates, then it's not a black hole anymore. So why don't you give up to this name, black hole, and come up with some proper name? If a black hole is indeed black and does not radiate, then, the information that goes inside it it's lost or destroyed.

[@wmpx34]

Black refers to visible light, my understanding is that it’s radiating heat or something. Not visible light.

[@HarryNicNicholas]

another great female guest.

[@sunroad7228]

Ali Bin Abi Talib is a distinguished figure in the Islamic history. The books he has written during his rather short life wouldn't be possible writing them in those volumes without a PC and a printer of the day. The stories written about him, his wife and sons have become what fills enough Alexandria's Library. People in the Middle East celebrate Ali & Sons more than anybody else - often by beating themselves parading streets with sharp metals, wailing. Today, many researchers defend their findings that Ali is actually a synthesised figure. The hypothesis that 'Information', present or vanished is now another evidence on the reality of black holes - might not be much different from the story of Ali - something never goes away as long as money thrown behind it (references suggest that the British East India Company et al has been instrumental in financing entities in Iraq, that promoted Ali among local population - since early 19th century). Black holes are a sub product of fossil fuels and they will 'evaporate' this time forever as the fossil fuels age comes to a close, rapidly.