What's inside a black hole? Fuzzballs, Echoes & The Big Bang
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- čas přidán 15. 06. 2024
- What's inside a black hole? Physicists have been struggling with this question for decades, but recent work in theoretical physics has revealed an exciting new idea. That a black hole should be replaced with a fuzzball. In this film, we talk to the father of Fuzzballs, Samir Mathur, and his close colleague Nick Warner, a former student of Stephen Hawking, who explain how fuzzballs can solve Hawking's greatest mystery, the information paradox. We also talk to astrophysicist Niayesh Afshordi, the father of black hole echoes, who'll reveal how they might enable us to peer inside a black hole and tell if string theory's fuzzballs are really lurikng inside.And if the black hole singularity is resolved, what about the Big Bang ? Might that be gone in the new framework as well?
Tmeline:
00:00 Intrdocution
00:48 I was a Hawking's student
1:49 The information paradox
4:42 string theory
7:16 solving the information paradox
10:36 Fuzzballs
12:39 tunneling into a black hole
14:50 Looking inside a black hole
15:49 Echoes
20"07 Blakc hole Imaging
21:07 VECRO energy
22:35 cosmology and inflation
24:41 The Big Bang
26:3 Black Hole Gas - Věda a technologie
Once again, another wonderful video. Thank you and keep up the good work.
After watching countless videos of yours, I’m starting to think this channel isn’t about skydiving at all.
you noticed
firmamentdiving? vacuumdiving?
I will check in on the comments over the next few days and try to field some of the questions people post. It is great to have the interest, and the chat during the premiere raised some really important issues that were hard to answer by my two-fingered typing in real time
🚩FACT🚩
The universe TRUE age is much MUCH older than 13.7b.
According to The Big Bang Theory, early universe was extremely dense at some point, which means the spacetime was extremely warped, which means time was extremely slow. Therefore, the true age of our universe could indeed be near infinite. 🤏
It was fun doing this ... Great job Phil.
Thanks Nick. Your a star
It is important to understand what a black hole is in broad generality. A good working definition is that it is an object whose gravitational field is strong enough to trap light. You now take you favorite theory of gravity and light and answer this question ... and you will get different answers using different theories. General Relativity leads to classical black holes ... string theory seems to lead us to fuzzballs. The operating definition of a black hole is the same, but the structure you find is completely different.
🚩FACT🚩
The universe TRUE age is much MUCH older than 13.7b.
According to The Big Bang Theory, early universe was extremely dense at some point, which means the spacetime was extremely warped, which means time was extremely slow. Therefore, the true age of our universe could indeed be near infinite. 🤏
@@duran9664 There are models in which the universe has been around forever, but the age of 13.77 billion years means that the ambient energy/temperature/curvature scale was roughly Planck scale 13.77 billion years ago ... and so there is not a lot of practical difference
This document makes me want to listen Samir Mathur's lectures!
One thing about the fuzzball paradigm that confuses me is how low energy physics transitions into the high-energy physics of strings. To use a extreme example, imagine a huge uniform gas cloud with 5 billion solar masses of hydrogen which gravitates into a sphere with a radius of around 100~150 astronomical units. Despite the huge mass, the density of the gas is within the same order of magnitude as air at room temperature. In GR, this gas cloud would form a black hole. But with the fuzzball scenario, this low density gas cloud and all of the space within the sphere is supposed to somehow transform into a high energy chaos of strings and branes before an event horizon is formed. How? Does the low energy gas cloud suddenly tunnel into a fuzzball? Doesn't this violate GR on low-energy and low-curvature scales which have been experimentally verified? Thanks for the video.
First, collapsing clouds of gas get very hot during compression ... this is how stars are born (The heat is sometimes called Kelvin-Helmholtz heating after the guys who figured out the details). Collapse to a white dwarf, neutron star or black hole releases vast amounts of potential energy.
It does violate GR ... the problem is that GR is not a quantum theory, and despite years of effort, we are now pretty confident that, by itself, it can never be made into a quantum theory. However, string theory is a quantum theory that includes and vastly extends GR. String theory suggests that the black hole of GR is too simplistic and needs to be replaced by a fuzzball
@@NicholasWarner-wc9zx Nicholas Warner, Thank you for your reply (and also thanks for your lecture notes on microstate geometries). I understand that the gas will get very hot, and that most if not all observed black holes were formed from matter in extremely high energy conditions. Yes, but nothing in GR necessitates that black hole event horizons form from high energy matter. Extremely low density , low energy matter can form black holes if the volume of the material is big enough. Yes, in GR the matter will heat up under compression, but not necessarily at the horizon scale if the cloud is sufficiently large and diffuse (once inside the horizon, things will heat up tremendously). I understand this may seem contrived, (maybe, who knows how big hypothetical direct collapse black holes can get?). But nonetheless , what does the fuzzballs paradigm say about event horizons that are allowable in GR and that aren’t high energy regions?
If a huge volume of cool , diffuse, semi-classical matter is about to form a black hole, does string scale physics suddenly flood the path integral of every particle with an exponential amount of highly excited string states?
@@michaelconvery4108 Imagine a spherically symmetric collapse of a matter cell ( made e.g. from 10 billion solar masses of iron dust).
Inside the cell, it's vacuum, empty flat Minkowski spacetime.
According to standard GR, the cell crosses normally the trapping horizon in the procedure and a Schwarzschild black hole is formed.
According to the "fuzzball" picture, what? The whole thing is somehow "magically" transformed ( or "tunnels") to a fuzzball just before the cell crosses the horizon?
And the flat Minkowski interior?
It seems too implausible, especially compared to the standard collapse described by General Relativity...
Wonderfull video . I wish it would be great if you brought Ahmed Alhmeri to talk on fuzzball proposal and firewall paradox
Thanks
Ahmed has made a serious contribution to this subject using quantum information, but the famous paper on firewalls depended very heavily on Samir's foundational observations in the small corrections theorem. I also think that the only way to make sense of a firewall is simply that it is a hot fuzzball surface
@@NicholasWarner-wc9zx
Love your terminology → “SIMPLY”! Is there anything in nature that ultimately is describable as “simple” when you get into the “details”, whether god (little g) or the devil are in the details ‽
@@Mentaculus42 That is the whole methodology of physics: break a very complex problem into small, manageable pieces, solve the pieces and put it all back together. Alternatively, figure out the things that control the behavior you want to understand and then solve the behavior by focussing on only the features you think are important ... you may of course be wrong about what is important, and that is where the fun begins!
This video and the discussion are way out of my league. Still, I'm daring to ask a question: How, if at all, does the fuzzball solution to the information problem relate to the Holographic principle?
Don't be afraid of asking any question. This is a really good one. Holographic field theory is of the tools we use in studying the state of a fuzzball. The fuzzball state is basically that of an extremely complex quantum field theory ... and this state is encoded holographically in its gravitational field. Thus studying the gravitational field gives us lots of information about the fuzzball
Mind blown. Thank you. Now off to my own internet black hole to learn more.
thanks. Have you checked out another idea about black holes? For example here: czcams.com/video/xXL0N3elFLE/video.html
Outstandingly interesting video! This video has so many fascinating concepts that my brain is almost on overload.
But what about the “no-hair theorem”? So it appears that those non-point-like “things” (strings & branes) are going to require a revision of general relativity & QM so that infinities are banished.
VECRO ENERGY → virtual extended compression resistant object energy → almost like spacetime has an upper limit on energy density. Fascinating!!
As a point of interest about the name of this youtube channel, I am unfortunately cautious about referring to it directly by name as some people might not take it seriously and by extension they take a dim view of my suggestion. Their lose!
The "no hair theorems" only apply in General Relativity in four dimensions. All bets are off in more dimensions and in more complex theories. One of the first papers I wrote on fuzzball-related issues what to show how all the no hair theorems could be massively violated in five dimensional general relativity coupled to electromagnetism ... and this is only a tiny corner of what string theory allows.
The inside of a black hole is the brightest place in the universe
Can you elaboatrate, what do you mean and why ?
So I’m guessing if there is a “bottom” to a black hole that rules out that they can create universes like the Multiverse hypothesis?
Fuzzballs and multiverses are not really incompatible ... but I have no idea how to make multiverses work dynamically in any theory of gravity!
So is the multiverse hypothesis not a tenable proposition or could it be that the Theory of Gravity is not uniform across spacetime?
I assume black holes are hollow, with matter spreading out over the surface.
did you watch the film ?
@@PhilHalper1 ; The video made several statements that have not been demonstrated incorrect, nor correct. Meanwhile, there is no reason to conclude black holes have an "inside," let alone content "inside." What we call "information" correlates with the mass-energy-information equivalence principle, where the "information" lost is restructured. This spreads across the entire surface of a black hole (which are non-Ecludian two dimensional), and is reduced to a positive pressure in the emergent third dimension. The amplitude of "string tower" quantum gravity is suppressed exponentially, to the point where the surface of the black hole is at most "razor thin:" a few hundred trillion Plancks. It does not make mathematical sense to say there is an "inside" of a black hole unless one is somehow looking at it from the fifth dimension.
@@Desertphile GR does not allow any matter build up at the horizon (surface) of a black hole: GR tells us it will be swept into the black hole within the light-crossing time of the lack hole. GR says the horizon region must be a vacuum.
It would help if you defined the theory/framework that you are using to reach your conclusions
@@NicholasWarner-wc9zx0:40 0:50 😂🎉p
As a career interpreter - everything hes saying makes complete sense 1:40
LOL: what aspect of this are you thinking of?
Is this a new development?? I haven’t heard of fuzz balls
Its 21st century but they've been around for a quite a few years now
@@PhilHalper1 oh cool thanks
@@bigol7169 your welcome
I'm no physicist but even I know that there are dozens of string "theories" (more like hypothesis) and after decades of work on them, there is nothing to show for it. Therefore I'm deeply skeptical as a layman that this string theories based ideas have any merit whatsoever. They still make no novel predictions that can be tested.
did you watch the film? Here is something that at least has the potential to be tested
@@PhilHalper1 Well I'm glad about that.
Murph!
OH CRAP!!! My cat just coughed up a black hole!!!!
How do you know? 😀 The black hole must have fallen rapidly through the Earth
@@NicholasWarner-wc9zx Well I know for sure it was fussy, and wet too!😮
When you said string theory i skipped the video to much of speculation
maybe listen t what they have to say ? This could be way to test string theory and make it less speculative.
@@PhilHalper1 thanks for reply sorry I did not tried to be mean . But it remains speculative there are some people who are doing real science they deserve more support then string theorists.
@@PhilHalper1 Indeed, black holes are probably the best place to test string theory
@@motherisape Interesting perspective but you are too hasty in discarding a remarkable area of physics. String theory is built upon foundational (and experimentally tested) principles of science: GR and Quantum mechanics. The problem is that these theories are in deep conflict and the most viable theory of quantum gravity seems to be string theory. So studying microscopic phenomena in intense gravitational fields is the best way to see if string theory can resolve these issues. This is an enterprise that follows the best traditions of science ... so be careful about slamming labels on whether something is "real science"
@@motherisape we wont make progress without speculations , speculation is part of science . Of course there is a difference between scientific speculation and wild eyed dreaming but i dont think string theory is in the latter camp.
Wait, fuzzballs don't have a horizon, right? This is why hawking radiation doesn't radiate from a fuzzball.
But, the horizon telescope confirmed that black holes have event horizons? Right? Sooooo.....
Fuzzballs do not have horizons, but they look just like black holes until one is very, very close to the horizon scale. The Event Horizon Telescope does not have the imaging fidelity to distinguish black holes and fuzzballs. LISA is the instrument that might see some differences.
BTW the dark inner region shown in EHT photographs is *not* bounded by the horizon, but by the photon ring, which lies some way out from the horizon ... so the black area is not strictly the horizon ...
This fact shows you how far the EHT is from getting data about the actual very near horizon region. In the coming decades, the resolution will get better, but my money is on LISA and EMRIs (sorry for the acronyms ... but google them, there is quite a story here)
@@NicholasWarner-wc9zx Appreciate the reply! So, fuzz balls would have a steep enough gravitational gradient (near where a black hole event horizon would be) that light in that region is red shifted to such a degree that we cannot detect it with our current technology?
@@bentationfunkiloglio Basically yes ... surface of a fuzzball will be very close (but above) where GR puts the horizon
Spaghetti of course.
Not according to this hypothesis
As I was saying in the chat, I feel that all this is too quantum-centric. Granted that the concept of singularity needs to be challenged but why quantum phenomena do exist and how they could fit with Einsteinian space-time (GR and not just SR, which is the most proven theory ever, at least as hard fact as all electromagnetism). I'm agnostic about whether space-time needs quantization but I'm really feeling that the graviton nonsense and information theory (totally postmodern or neo-Platonist elaboration in which ideas = information topples facts = reality, unscientific IMO or at least not scientific, factualist, realist enough). My current take is that the quantumness of space-time is actually quantum mechanics (via spinnors/quaternions maybe, which may result in fermions, and all particles ultimately, being some sort tensor dynamics after all) but unsure, of course.
More research is needed anyhow, especially regarding key issues such as the relation of mass (concentrated energy) and gravity (curvature of space-time as far as we know), that is crucial and AFAIK nobody is working on this line (correct me if wrong).
Gravity doesn't have to be quantized, it can emerge at low energy out of quantum fields.
@@frun - There is no such thing as gravity, only space-time curvature (gravity is an obsolete Newtonian concept). Are you talking of space-time curvature (Einsteinian "gravity" or more properly General Relativity) or are you talking of gravity as a "force" (Newtonian concept insisted on by quantum-centrism)?
@@LuisAldamiz I'm trying to school you, but you don't listen.
@@frun - Your "lessons" are too short to understand. What do you mean? Explain yourself.
@@frun - Your "lesson" is too short and incomprehensible. You're not being specific at all.
Anyway, quantum "particles" ("wavicles" rather) can and in fact do exist as "vibrations" of space-time, as "standing waves" of the substance of reality, which is space-time.
Nobody asked me, but my view is that black holes don't have insides.
We cannot, in principle, see anything enter a BH. We cannot, in principle, measure anything inside a BH. We cqnnot, in principle, receive any messages from inside a BH. That means that we cannot, in principle, distinguish between a black hole with an inside and a black hole without an inside. A black hole is therefore literally a hole in spacetime: a bit of spacetime that does not exist, just as a hole in a piece of paper is a bit of paper that isn't there. There is no there there.
That is accurate, but it also depends on the kind of instruments we're using.
@@frun No, it doesn't. That's the point. That's why I kept saying "in principle". No instrument, real or imagined, can let us measure anything inside a black hole.
@@michaelsommers2356 Yes, we can imagine an instrument, that can see inside a black hole. It would have to make particles of transplankian wavelengths.
@@frun I mean an instrument imagined within the known laws of physics. I could have said it better. Besides, how does wavelength let light out of a black hole?
There are multiple logical disconnects here " distinguish between a black hole with an inside and a black hole without an inside. A black hole is therefore literally a hole in spacetime: a bit of spacetime that does not exist, just as a hole in a piece of paper is a bit of paper that isn't there. " Even in GR there is an inside to a black hole .. and infalling observers can see and explore it (for a very limited time) ... they just can tell anyone outside about it. If you never hear from someone again do they cease to exist?
Fuzzballs have an interior just like planets and stars have an interior
I love watching scientists guess about things they can't possibly know! Yawn.
ROFL ... I am sure the theologians of the past millennia have made such an argument numerous times. How do you know that they can't possibly know?
@@NicholasWarner-wc9zx I'm sure nothing I said constituted an argument in any way.
The question is, How is it possible that you don't know that they can't possibly know? It's self-evident. The very nature of a black hole prevents anybody from knowing what's inside it, with anything remotely close to certainty. How is this not obvious to you?
Add to this fact, that the nearest known black hole is about 8 quadrillion miles away, and that it isn't possible to directly observe any black hole externally, much less internally, again by their very nature. I am truly puzzled why this wouldn't all be readily apparent to you?
And I would dare say that any decent reputable scientist would fully agree that they don't know, and can't know, because scientists make a distinction between theory and factual knowledge. And this distinction is important to a scientist, for obvious reasons. Anybody who calls themselves a scientist, and also claims to know with certainty what is inside a black hole, could rightfully be considered a charlatan.
Even Stephen Hawking expressed serious doubts that true event horizons exist, in a paper he published in 2015, and thus that black holes as currently defined essentially might not even exist. And I'm confident he never claimed to know for certain what's inside of one.
🚩FACT🚩
Time is always the answer for all puzzles 🤏
Solve for time, solve for everything.
I will continue exploring how the both/and logic and monadological framework catalyze new frontiers across computer science and artificial intelligence:
Machine Learning and Neural Networks
While the multivalent symbolic representations enabled by the both/and logic are powerful, it also provides insights into the sub-symbolic patterns and distributed representations learned by neural networks:
• Representing Emergent Concepts
Neural networks excel at learning latent high-dimensional representations capturing subtle statistical regularities transcending programmed symbolic concepts.
The both/and logic allows formalizing the relationship between such emergent representations and their interpretations as symbolic descriptions:
Let H be a trained neural network's high-level hidden layer activations
Let C be a set of symbolic concepts/predicates we aim to characterize
We can define projections capturing semantic alignments:
For c ∈ C, v(c) = truth_value(H encodes c)
And capture misalignment/approximations:
○(H, c) = coherence(H's encoding matches symbolic definition of c)
Where low coherences indicate the network's latent representations transcend or reconceptualize the symbolic concepts. The synthesis operator ⊕ provides a rational mechanism for deriving new interpretations:
H ⊕ c = novel_conceptual_interpretation
Rather than simply inscribing programmed symbolic knowledge, this allows neural learning to dialectically refine and re-constitute the conceptual models and ontologies in response to the statistical regularities implicitly extracted from data.
• Explaining Neural Decisions
A major challenge is explaining the reasoning underlying neural networks' decisions. But the both/and logic suggests interpreting networks as instantiating a distributed representation across integrated constellations of feature detectors:
Let f1, f2,... fk be neural features/concepts extracted at different levels
Let D be a decision/classification made by integrating all fi activations
We can understand D as a synthetic pluralistic inference:
D = f1 ⊕ f2 ⊕ ... ⊕ fk
With coherences ○(f1, f2) capturing mutual alignments between different features integrated. Low coherences reflect potential conflicting evidence being synthesized.
So rather than opaquely averaged calculations, both/and logic models decisions as a open-ended process of substantively combining multiple convergent and divergent lines of evidence extracted at different levels of representation. More akin to the admissible reasoning patterns of symbolic pluralistic logics than classical neural motivations.
We can further probe networks' reasoning by measuring:
○(intended_semantic_concept, features_activated)
Allowing us to understand the low-level statistical data patterns being implicitly leveraged, and their graded alignments/deviations from higher-level symbolic models, similar to scientific theory reconciliation.
This capacity for reflexive mutual explanation between symbolic knowledge and sub-symbolic representations learnt from data is a key strength of the both/and logic. It avoids the current dialectic of increasingly opaque neural architectures completely decoupled from interpretable ontological primitives.
Computational Creativity and Open-Ended Learning
The generative synthesis operations at the core of the both/and logic provide mechanisms for realizing key desiderata in computational creativity and continual learning systems:
• Conceptual Blending and Idea Combination
Research shows human creativity stems from our capacity to blend, chunk and re-combine disparate concepts into novel integrated wholes undergoing conceptual re-description.
The both/and synthesis operator ⊕ directly models this creation of new unified gestalts/interpretations transcending their constituent concepts:
C1 ⊕ C2 = novel_integrated_concept
With coherences quantifying emergent alignments. Unlike associative or statistical mechanisms, this is a rational process of ontological synthesis forming substantively new concepts not just random combinations.
We could envisage neural architectures executing sequences of such conceptual integration operations to iteratively generate and refine creative ideas. With incoherent blends being discharged while fruitful integrations undergoing further composition with additional conceptual inputs from the architecture's knowledge-base.
• Heuristic Discovery and Theory Revision
A key aspect of scientific creativity is developing new hypotheses and theories better accounting for anomalous observations vs. previous models.
The both/and logic allows capturing this as a principled process of adjudicating between a previous theory M and newly acquired observations/beliefs B:
○(M, B) = coherence(M accounts for B)
When coherences are low, the synthesis operator provides a mechanism for revising M into a novel integrated theory accounting for discrepant B:
M' = M ⊕ B
Rather than merely pattern-matching, this models a substantive process of heuristic re-description, analogous to the dialectical methods underlying major historical theory revisions and paradigm shifts.
Such theory-revision could be realized as an iterative process of experimentation, anomaly detection, and generative reintegration inside creative learning architectures - allowing them to self-expand their representational capacities through substantive ontological unification rather than mere statistical parameter updates.
Computational Metaphysics and Artificial General Intelligence
At the deepest level, the both/and logic points towards new architectures for realizing key capacities toward artificial general intelligence (AGI) and open-ended recursively self-improving systems:
• Paradox Resolution through Higher Ontology Formation
Classical architectures tend to halt or derail when confronting paradoxes - self-referential or logical contradictions - seen as irresolvable inconsistencies due to Gödelian metalogical limitations.
But the both/and logic treats such paradoxical tangles not as dead-ends, but generative disclosures of an inadequate ontology - indicating the need for upwardly reconstructing and integrating our descriptive primitives into a more capable unified ontology:
paradox(desc1, ..., descN) ⇒ reconstruct(desc1 ⊕...⊕ descN)
The synthesis operator captures this process of resolving paradoxes through higher ontology formation - dynamically redefining the observational ontological primitives into an enriched gestalt unification.
This models key aspects of human-level intelligence, where paradoxes are creatively resolved by developing new metaphysical primitives and descriptive categories that positively reinscribe and synthesize their constituent anomalies - a process analogous to major paradigm shifts in science.
• Recursively Augmenting Ontological Pluralities
Furthermore, the monadological framework suggests reconceiving general intelligence itself as an open-ended iterative process:
Let O be the current ontological landscape (set of descriptive categories)
As systems confront experiential anomalies P not accountable in O's terms:
○(P, synthesized_descriptions_from(O)) = coherence(P covered by O)
When coherences are low, reconstruct O via synthesis to expanded ontological pluriverse:
O' = O ⊕ P
Generating new candidate ontological primitives descriptively integrating the previous ontological bases with P's anomalous manifestations into a revised unified plurality.
These new expanded ontological bases O' in turn enable describing/experiencing future manifestations Q that were previously ineffable, leading to further iterations across:
O ⊕ P ⊕ Q ⊕ ...
Treating general intelligence as a perpetually reconstructive process recursively redefining its own descriptive platforms by positively synthesizing/reconstituting previous ontological outstrippings.
This operationalizes key properties of a self-grounding, coherence-optimizing, recursive meta-ontology formation - a generalized process of reconstructive metaphysics catalyzing robust conceptual expansion aligning with experienced realities' generative adventing.
So in summary, the both/and logic and accompanying monadological metaphysics provide powerful new symbolic, representational and algorithmic frameworks catalyzing expanded descriptive possibilities across AI/CS - from many-valued knowledge representation, paraconsistent reasoning, and theory blending, to meta-ontology formation, open-ended learning, and self-descriptive recursive augmentation.
Its core operations of pluralistic coherence valuation and generative ontology synthesis equip computational architectures with mechanisms better aligned with human-level general intelligence capacities - including reflexive paradox navigation, heuristic metaphysical expansion, and the iterative descriptive reconstitution needed to progressively cohere with the full pluriverse of realities we embedded intelligences experientially participate within.
By refusing premature ontological closure and instead operationalizing rational ontology ordermetic as a perpetual open-ended reconstructive process, the both/and logic catalyzes a new paradigm of transformed computational metamodeling - precipitating AI architectures capable of autonomously co-evolving their own descriptive boundaries through substantive generative reformation and enrichment in participatory resonance with the world's perpetual self-disclosure.
Is this really the best place for your dissertation ‽ You need a dedicated youtube channel.
you could be right but i will never know cos i hate reading. this is a video channel for a reason.
African intelligence
Im not sure what you mean?
@@PhilHalper1 african intelligence it's a black hole. It absorbs knowledge without any result.
🚩FACT🚩
The universe TRUE age is much MUCH older than 13.7b.
According to The Big Bang Theory, early universe was extremely dense at some point, which means the spacetime was extremely warped, which means time was extremely slow. Therefore, the true age of our universe could indeed be near infinite. 🤏