Black holes might be dark stars with layers: New solution found
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- เผยแพร่เมื่อ 1 มี.ค. 2024
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Do black holes even exist? You might think the evidence is overwhelming. But in a new paper, physicists have shown that Einstein's theory of space-time allows another option, it's that black holes might be layers of shells with dark energy inside. I had a look, and here's what I learned.
Paper here: iopscience.iop.org/article/10...
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#science #sciencenews #physics - วิทยาศาสตร์และเทคโนโลยี
Depicting the physicists addicted to finding solutions of Einstein equations as cats eating some herbs is stunning.
creativity inspired by limitations of stock footage is an underappreciated phenomenon
@@SabineHossenfelder
It's the seizure of unsound minds.
😂😂
I’ve been saying for a while now that “solving Einstein’s equations” is nothing but video games by another name. The whole lot of it is video gaming and idea popularity contests. None of it reality. It is a shame the publications of these leads so many to proverbial war against one another’s beliefs… like history repeating itself, again and again. So, much of it so conveniently unfalsifiable… at least not within our own lifetime. As such, there is never anything truly risked.
It’s catnip. It’s cannabis for cats.
Doctor: Wide Sabine does not exist, she can't hurt you
Meanwhile wide Sabine: 👁️ 👄 👁️
It's us who become wide relative to Sabine as she passes the event horizon 😆
@@Broockle Age old 'frame of reference' issue. Good one.
Beware “wide not” counter-Sabine
I laughed mute then I would never admit
Hahaha wow an actually funny comment
💪🌏🫸
🦵🦵
1:37 stuff like this is why I love this channel
Hearing Sabine say "prof" is the highlight here.
Publish or perish is such a thing. Thanks for getting us the real facts.
Knowing is half the battle. Brilliant may be the other half.
do physicists think singularities _exist,_ or is it more an "our math is messed up but we don't know how to fix it yet" marker?
I don't know any physicist who thinks that singularities are physically real. Then again that doesn't mean those physicists don't exist!
Most scientists don't really believe in a singularity. But any guess as to the size and composition of the object (if any) within would be a guess, so they don't talk about it. All they know for sure is "this is what the math says".
I'm pretty sure that whenever singularities appear in a model, that model is either wrong, or incomplete, or both.
@@VikingTeddy
If math proved it we wouldn't be asking questions. Thinking humanity knows any math is as insane as a pig flying. Logically any math we depend on that doesn't support all math means we don't know any math or that there is no math. Math is a human invention like all we do. Humanity can not prove any knowledge isn't flawed or represents reality.
That's kinda the problem. We don't know which it is.
Sabine: Black Holes = Hotel California
Welcome to Hotel Blackholifornia
They break the laws of physics so that wine becomes a spirit.
You can check in anytime you like but you may never leave...
Did the " scientists " even consider the notion that nothing can enter a black hole. Surely someone has, they didn't just assume that Matter falls into a black hole do they? I can go on and on. Did the inflationary hot big bang really happen as we think it did. And ultimately, are our finest thinkers going down endless rabbit holes that may take them exactly to where they started. Like I said "on and on". But anyway, I love science and the conceptions of these wonderful people, whether right or wrong. 😊
A lot of talk noone knows!
Thank you, Sabine, for making the fine subtle point that there's a difference between things that could exist according to the solutions to Einstein's equations and things that actually exist. I might that add that for things to actually exist, there must be a physically allowed process or series of steps to arrive at that final state, it's not enough for the final state not to violate the laws of physics to actually exist.
Like there isn't proof that gravitational waves exist
@@whiteeye3453there isn’t proof that any physical object exists. Doesn’t mean there isn’t evidence for it
@@olbluelips and evidence is ither fake or hoax
@@whiteeye3453 and what's your worldview, exactly
@@olbluelips no gravitational waves don't exist
"Disappointingly Human" is a new favourite of mine.
hihi
Agreed! Will use frequently.
@@greatPretender79 We need a collection of Sabine´s "best of"
It feels like something Glados would say
Sabine, I just wanted to say that in your ad read, when you mentioned how much probability you had forgotten, that really warmed my heart. Sometimes it's embarrassing to feel proficient in a field (for me, Biostatistics) and to realize how much of another field you have forgotten. If a smart person like you can forget stuff, then maybe there's hope for the rest of us!
Agreed.
Every time I learn someone's name; I worry I'll forget how to tie my shoelaces. 😮😅
You might be surprised how often that PhDs and Professors have to look up formulae in thei compendiums.
We're human, not machines.
I forgor 💀
With increasingly narrow specialties, the path to becoming an expert is inevitably going to include a lot of forgetting. It's only human, y'know? Now, if we could control whether we forget Something Important that will Inevitably Come Up or That Embarrassing Preschool Situation...
This is a good thing (fellow biomathematician here).
I could not get rid of the mind poison of probability fast enough once I graduated.
So, our math professor gave us an example of how math can be used to calculate the "real world", but if one isn't careful with where limits are placed and so on, then you get things that are mathematically correct, but has nothing to do with reality. His example was with derivatives concerning car breaks. They could simulate how the car would behave while breaking by...I've forgotten already, it's been like 6 years, but, basically, the car's speed would start approaching zero, then dip bellow zero, then back over, and oscillate like that until it approaches zero (imagine a sinus wave, but slowly converging to zero, that's how the graph looked like). And his student presented the graph to him proudly, cause it was apparently a tough calculation. The professor looked at it and then asked - "If you step on the breaks while driving, do you start rocking back and forth until you stop completely?"
Is it possible that something like this is happening here as well? There's a mathematically sound solution with these gravistars that doesn't actually conform to reality? Like the "mathematically correct" solutions to warp drives that require negative energy densities and more power than the entire universe can generate?
If you step on the breaks while driving, do you start rocking back and forth until you stop completely? No, not at the start, but possibly at the end, at least for the occupants.
@@zinken255 hehe
Yes, that's correct; the solution is stable,like a pencil balanced perfectly on its point, but there's no real way to produce it naturally. It could exist,if you could magically make it, but we don't know HOW it might be made. Whereas 'regular' black holes will just happen.
I just love the cool names they come with: gravastars
Sounds like a gravy brand
@@TheRABIDdude I was thinking more like Space Jam.
Thank you sharing such an interesting concept. Certainly worth thinking about. We have so much to learn.
Fascinating stuff indeed! Thanks, Sabine! 😃
Stay safe there with your family! 🖖😊
"👏👏👏 Sabine, what are you doing!?" 😂
You have an episode from two months ago, explaining Kerr's new paper, which I suspect answers many of the questions raised here. First, in practice, there are no known black holes with zero angular momentum. Not only is it difficult in practice to get mass to stop rotating completely but also quantum mechanics implies that the ground state of any particle having angular momentum is nonzero.
If I understand correctly, Kerr's paper suggests that angular momentum turns the Schwarzschild point of singularity into a ring. Matter tends to follow toroidal paths that take forever in proper time to approach the singularity. I never specialized in any of this, so I can't say much more useful.
That is how I understood it. Importantly, he suggests that the centrifugal throw of rotating black holes can counteract the pull of gravity within their event horizon, potentially creating an inner region where matter and light are free to move almost normally (thus avoiding the supposed "ring singularity"). That's the interesting region. Perhaps said gravastar (or a baby universe even) could exist within it. I do like this more sensible approach to explaining black holes
Your videos are delightful and amazing Good job !
I never imagined I would get to experience a Sabine & Flextape crossover but I am glad I did.
Isn't it the case that the analysis of gravitational waves uses statistical methods and filters that are trained on our expectation of black hole mergers and we'd have to redo analysis from raw data against a gravastar statistical model to really be sure?
Sort of. To find merger candidates data is filtered to look for the 'chirp' expected of a merger, a signal rising in intensity and frequency that appears at both LIGO detectors at the right time. In this way only merger signals that fit the general pattern of what we expect will be processed,something which can be said to be limiting.
On the other hand a lot of work has been done on identifying any other signals present, for novel processes and to try and find ways to eliminate noise. So we know we're not missing any significant weird signals.
The LIGO detections require gravitational wave emission from two inspiralling dense masses,but not necessarily black holes.(For example we have at least one neutron star merger on record.) So we should be able to identify mergers of things that are like, but not black holes. We can also predict what signal other kinds of merger would produce and check LIGO data for that. Which is what's been done with the gravistar model; there's a big enough discrepancy there that we know LIGO should detect it and it shouldn't resemble a black hole merger. The difference is just too great.
I would say yes, though, I doubt resources will be spent to study anything that strays this far from the main stream.
OH wow. This is so interesting to me right now . I've been very interested in gravity among many other things lately. Your videos are superb. Thanks Sabine!🤓🙏✨️
Awesome as always! Saw you interview with the philosophy show from the swiss. Would love , if you would do a special series, where you dig deeper into the questions about whats the matter of the universe, does free will exist and all that. Maybe you could even interview other scientists too.
I've always thought a black hole is named for its appearance, not for what it actually is, there is no doubt the gravity culminates from a huge amount of trapped material, so no way is it a porthole to another dimension/realm. Actually you could say It's behavior is the opposite of a star, a star emits energy, a black hole consumes it, for all we know the colour of a black hole could be Ultraviolet or Grey, unfortunately the gravity will never let us see, I think a black mass would be a better description.
John Mitchell was the bloke who first thought of black holes (way back in 1783), and he called them dark stars. Reading his wiki he also thought up the balance used in the Cavendish experiment. Also into earthquakes & magnets, smart dude.
Really loved the speed ticket joke
Hello Sabina, as always, your videos are very interesting. Could you someday talk about the theory that suggests black holes could actually be quark stars? It's proposed that after the level of gravity resistance of neutrons, there could be another level of nuclear resistance in quarks. Regards
Once more, as the rest of all of your posts, loved it.
Ok but what if.. they’re not stars, but superatoms
👀
Or cheesecake
No.. as is they have less in common with stars, and more in common with atoms.
Follow electron shell theory, and the event that strong force collapses space.
I think you just described a neutron star my dude.
I mean.. you could be correct!
The theory came from stacking matter (theoretically) over and over until you collapse the electron shell, and then searching for a comparable observation.
At some point the object gets so dense photons do not emit, and what would you call that?
Note* TH-cam wiped my first attempt to respond
I have no formal education on any of this. I always thought since the universe started in a super dense state, black holes were just returning to that state. Maybe the stars that collapsed were formed of larger chunks that didn't become stable enough. Simplistic I know.
Check out anytime. Since it takes forever to hit the center, perhaps Rovelli is right, when it gets down to a quantum squeeze size, perhaps it bounces back out?
Loved the Eagles reference! Well done!!!
Very cool. Reminds me of the models of rotating black holes which have a doughnut shaped ergosphere and an inner event horizon, PBS Space Time did an episode a couple years ago on this.
Thank You! Stéph.
Could this be extended to a continuous solution? Instead of nested shells of matter, each right where an event horizon would normally form, you could have a continuous distribution of matter that's right at the edge of forming an event horizon at every point within itself. If increasing the number of nested shells improves the stability, would this type of continuous distribution be perfectly stable?
I enjoyed the humor in this video. Thank you!
I like the idea your Proff gave of making two predictions, one for the thing and one for the exact opposite. This complies with how I view a similar idea in statistics where you make a hypothesis (a thing is a thing) and a "Null" Hypothisis (a thing is not a thing). I feel testing an idea and the exact opposite of that idea helps lead to evidence for and against the idea.
Great stuff. More please.
Wonder-full times 😂🎉 your videos have just been getting better. I can see the bottle-neck opening, this year is gonna be wild!
FINALLY Sabine touched on my favorite black hole theory!
always a great video! and funny! and wise.
You are quite inspiring...not always totally easy to follow but still...🙂
Sabine, I have been watching your excellent videos for years and I love them (however, that doesn't necessarily mean I understand them). I have noticed recently, that you appear to have developed an English sense of humour - Bravo!! Is this something you've always had or is it part of your ongoing 'development' as a brilliant content creator? Kind regards, Jim - England x
I love the humor in these videos. The cats with the catnip was just *chef's kiss*
Ms. Sabine, I was wondering if you'd heard of the recent statement from Kerr regarding the singularity issue and any thoughts you might have.
Love the work ♡
Thanks for the great explanation! You’re funny, I love it ❤
The final stage of a black hole's evaporation, depending on its initial size, could leave behind either a tiny black hole or a stable, dense object resembling a "dark star". Suppose a quark star or neutron star is in the center of a 'Black Hole' with special matter (Infinite compression is not decided by zero) and particle-antiparticle pairs near the Event Horizon. In that case, one particle falls In, and the other escapes. If the negative energy particle escapes, then the laws of energy and matter conservation are resolved. Also, the resulting mass from the 'Dark Star' or dead star which has an evaporation leaving a dead star, could account for some of the lost mass attributed to dark matter. Dark energy, or the dark particle escape from the 'Black Hole', accounts for some of the 'Dark Energy' and would probably be stronger nearer a 'Black Hole.'. I think if we can find the remnants of a 'Black Hole' or dead star with extreme density mass, we could work backward from that.
Sabine I’m not a physicist but I am doing thought experiments of timeless physics and now I have a promising result that has potential unify physics, specifically cosmology with quantum mechanics and statistical mechanics.
I was able to show how conservation of energy emerges from very simple fundamental principles.
What do I do now?
Do I self learn deeper until I’m at the level of a master degree? Or do I reach out to someone who can help me develop this proper? My idea shows how universe can manifest physically from a conceptual space, it shows how the universe got its boundaries etc.
It all started by reimagining gravity as the least action through a mass-energy field
Sabine always with the fun.
I'm so glad that you pointed out that the singularity in a black hole is a purely mathematical entity. If the Schwarzchild solution is correct, we can never know what is at the centre of a black hole.
Of course, I have to acknowledge that the Schwarzchild solution is for a non-rotating black hole, which almost certainly cannot exist unless someone finds a way to break the conservation of angular momentum.
I've always pictured black holes as shells of frozen time. Objects seen falling toward the horizon approach light speed, so appear shorter in the direction of travel and are never seen to cross. As they approach c, length becomes zero and forms a shell, preserving information about it at the EH surface. Frozen time prevents a singularity as viewed from the outside Universe. The increased mass means the horizen moves a tiny bit away from the center for the next shell. When the black hole evaporates, information in those shells imprints on the Hawking radiation, preserving it.
That's quite neat.
What is time??
@@krox477 I think I know what time is until someone asks me to explain it. Then I know not.
@@aadilnaqvi4399 And since time in the outside Universe goes by increasingly faster near the EH from the infalling object's point of view, the black hole evaporates before it has a chance to reach the center to form a singularity.
Sabine, I went to the Black Forest to visit my ancestral village but in fact it is a very green place. I demand an explanation for this!
I had a "prof" grade 7 science teacher like that, he had great answers but i never found out what they were.
As soon as I asked a question, I always had the leave the class, sit outside and stare into space.
Thats why i like it so much.
I remember first hearing about gravastars several years ago. And MECO's. You need to do a vid about these too.
From EHT observations, the exterior of GR black hole solutions has been tested to decently high precision. However, a significant bit of discomfort I have with black holes is that the interior of GR black hole solutions is an untestable prediction, so I'm inclined to believe that the existence of black holes with GR-conforming interiors is as much an article of faith as any of the alternatives. Eventually near-horizon effects should let us determine if there are exterior deviations from GR, though, but depending on how close the QG corrections to GR are to the Planck scale, we may, for any given black hole, have to wait for approximately one evaporation timescale before any differences are observable.
Are those gravastar layers *turtle* shells? I mean, it could be turtles all the way down 🐢.
"It's full of stars." --David Bowman, about to get shredded
Very very very very very very INTERESTING!!!
I recently learned what the “nothing can escape a black hole not even light” means. It’s the escape velocity that is greater than the speed of light and since matter can’t travel faster than light is unable to ever get past that high escape velocity. That’s a big point I didn’t understand. But past the event horizon if you had some way to travel faster than light, you could possibly escape. That’s a bit exotic and I think probably not possible but I like the idea.
When something is uncertain or unknown, I think it is good science to consider and idea and its opposite, and make contrary predictions based on each.
Greiner's Field Quantization is my favourite introductory book about Quantum Field Theory
Hey right on, cool video😊
I think I came up with something like this years ago. I wonder if it's similar. I said in large dense objects like a planetary core, if the thermal pressure overwhelmed gravitational pressure, there could be a relaxation through the inducement of a quantum state, primarily lowering the energy via degeneracy... it was a pretty approximate idea, kind of a Linus Pauling. I had put it out on Twitter, I wonder if it was annoying because it was smart or stupid. I'm just a chemist
Right, and the # of quantum states would increase as you went closer to the center. Layers maybe.
Ah, but what of the old "what would happen if I fell to the center of the earth?" problem? If the center of ANY mass is where gravitation is cancelled out by the surroundings, should not a black hole obey the same laws? Instead of a singularity at the center, a near singularity as a shell around the center with either normal matter(super high elements?) or absolutely nothing?
It's been a long time since I thought about this, and I'm not a physicist, but I think you did a perfect 180 @@starventure
Actually, that might be a quantum mechanics with gravity in it. Hey, maybe you're the smartest man in the world@@starventure
@@AB608052 The power of alcohol...
Somethings that bothers me about the typical blackhole model (and I'm no expert, so wouldn't mind having someone correct me if I'm wrong) is that we say someone falling in to a black hole, especially a super massive one, wouldn't really notice they're falling it, but there's two things they *would* see, and that's time-dilation causing both the light coming from the universe to blueshift, and hawking radiation to also "blue shift". That someone falling in to the blackhole would never enter it within the lift-time of the external universe, so the blackhole would evaporate before the object would pass the horizon. So it seems like passing the event horizon is purely theoretical thing that would happen under a static, unchanging blackhole. But from a more wholistic perspective, the object would be fried by gamma rays and extremely high energy hawking radiation, it's quite possible the hawk radiation would apply outward pressure too. The only time the blackhole would truely grow is if matter outside the blackhole could cause the horizon to expand outward. Also one of the spacial dimensions becoming "time-like" seems rather crazy and I hazard a guess that would be fairly observable phenomenon as well. So I've been very intrigued by alternative models.
What a great channel !
Interesting video Sabine. What I want to know is what separates the layers in these so called dark stars? 🤔🤔
Sabine knowledge for its own sake is not bad. A lot of math was developed before we knew what was it for. Think topology or non Euclidean geometry and so on. I think it's fascinating that you can find gravestar inside others. Now if someone had a question for you where should it go?
You have the best science channel on All of Youbtube. Respect on your name !.
Sabine, does this mean that black holes are behaving as atoms do? Exhibiting properties similar to the electron shells and the nuclear shell model?
To me it always sounds like: Star -> collapse -> magic -> singularity. But what is the magic? Since time slows down the smaller and heavier the "thing" becomes will it ever reach point zero? Or will it just become infinitely slow and never form a singularity?
"The fact that it's an answer to the equation doesn't mean it actually exist"
But does that mean that it might be able to exist, even if it doesn't happend naturally? (In an artificial/experimental setting for exemple?)
I guess it could also show that there is some constraints missing?
Thank you; this video is awesome. Am I incorrect in recalling Carl Sagan's COSMOS television series mentioned stars and galaxies might be in black holes? I thought universes can be infinitely scalable.
Sabine, would you mind doing a video to explain the following to us like we're 5 years old. Here is the thought experiment:
1. Let's say we have a star or mass that is slowly gaining additional mass by consuming nearby planets and/or stars
2. As it gains mass it's density and gravitational force increases and it's diameter would either grow or shrink (please explain which is correct)
3. At some point it's gravity reaches the point at which light passing close by would be refracted (lensing)
4. Then the gravity reaches a point where light from the surface can no longer escape
5. At this point it's still just a mass that is still just absorbing masses that get drawn into it
6. So effectively this is what's referred to as a black whole, but underneath the event horizon it's just a large mass with large density and gravity
7. There should be nothing that dramatic occurring that would all of a sudden reduce the inner mass to a singularity where all the mass just magically disappears
8. So isn't this a simple explanation for how black holes form and what they consist of?
Again, please explain why not like we're 5 years old. Thanks so much. Peter
There's a whole bunch of problems with this.
A minor problem is that as a star gains mass it increases its fusion rate, its temperature and thus the outward force of radiation and matter. Larger stars resist adding more mass, above about 100 sun's worth a star can't grow larger feeding on gas. Above about 300-500 sun masses it's actively ejecting entire sun's worth of mass as a powerful solar wind. (Incidentally this means that more massive stars get larger, not smaller as they gain mass, but their cores get smaller and more dense.)
The major problem is that as more mass is added, objects in the star must move faster to avoid compressing. A star so massive that light cannot leave its surface will have particles just under its surface that need to move faster than light to avoid collapse; no matter can do that without having more than infinite energy. So all the particles in the star will be too slow to avoid collapse and will all collapse inwards forever. Creating a 'traditional' black hole.
Before this though there are other processes that will kick in. Core-collapse Supernovae happen when a star's core gets too heavy and collapses, forming a black hole or neutron star,Type1a supernovae happen when a white dwarf gets too massive and instantly fuses,vanishing in a blast of energy. Pair-instability supernovae happen when a star's core gets too hot, creates antimatter and collapses.
We've even seen a few neutron star mergers, where two neutron stars collide, fracture and form a black hole with the release of a massive blast of energy and heavy elements.
I'm not able to give a simple answer. However, there are classical examples in astrophysics where matter accretion occurs, e.g. en.wikipedia.org/wiki/White_dwarf#Binary_stars_and_novae . About the conditions for the creation of a black hole see en.wikipedia.org/wiki/Black_hole#Gravitational_collapse .
About question 2: That's difficult to answer and depends on which object we're talking about. For example, en.wikipedia.org/wiki/Stellar_evolution#White_and_black_dwarfs states that higher-mass white dwarfs have a smaller radius than lower-mass ones.
About question 3: Light is always "refracted" by gravity. It's just that the effect is normally so small that it's barely observable. But stars are massive enough to cause measurable gravitational lensing. And black holes even more so.
About question 4: At that point a black hole has already formed. Matter always undergoes gravitational collapse, and if there is no physical process that is able to generate enough pressure to stop the gravitational collapse, then it will collapse into a black hole / singularity. Typically, in stars the process that generates the pressure to stabilize the star is the fusion reaction inside the star. Once that fusion reaction fizzles out the star quickly collapses. If during that collapse it becomes dense and hot enough to allow fusion of heavier elements then that fusion process will halt the collapse until the fusion reaction fizzles out again, and so on. In the end the star's core collapses either into a white dwarf or a black hole or something more exotic (e.g. neutron star), depending on the mass. If at some point an event horizon forms (i.e. light can't escape) then the black hole has already formed and the matter inside of it is quickly collapsing into a singularity.
About question 6: For all we know that mass is concentrated into a singularity. The mass limit at which matter collapses into a black hole is the Tolman-Oppenheimer-Volkoff limit, and is somewhere between 2 and 3 solar masses.
About question 7: Wrong, see 6. Also, the mass doesn't disappear. It's part of the singularity. We don't know any laws of physics that would prevent the mass from quickly collapsing into a singularity. We just expect that there are unknown laws that prevent if from being concentrated into a point.
By the way: here is high-quality animation of the visual effects while falling into a black hole: th-cam.com/video/4rTv9wvvat8/w-d-xo.html . Yes, the event horizon is not "magical" and the laws of physics still work normally inside of it.
I would suggest a gravastar forms due to the curvature of space time at the event horizon preventing bosons from communicating force in the direction out of the gravastar leading to the quantum foam becoming fractionally dimensioned, e.g. 2.5D 2D plus "in". A bit like Apollonian sphere.
I'd also suggest the quantum foam could be responsible for the "random" aspect of gravity in Oppenheim's post quantum gravity model (that seems to negate the need for dark matter or dark energy)
Please do a video on plasma cosmology and the electric universe theory. I would love to hear your thoughts on these topics
Not allowed . It's forbidden. Even the work electric is forbidden
@3:33 😂😂" quantum something and gravastar" got me hard
Clearly there is some kind of fusion reaction going on inside black holes that produce gravimetric (dark) energy, and form extremely energy-dense spatial particles that create a different region of space with its own fundamental properties. Hopefully further research on QCD can determine what this reaction might be.
Hello Sabine,
Me thinks that the commercial for Brilliant at the end of your video (~7:12) contains a glaring error. If 32 people saw movie ‘Blue’, and 28 people saw movie ‘Yellow’, then the combined audience for both movies is 60. If 15 people (green area) saw both movies, then the ticket share of those who saw both movies would be 0.25 (15/60) or 25%, not the 0.15 shown as the ‘correct’ answer in the spot.
However, since we are looking at individuals, not ticket sales, we need to subtract the 15 tickets for the folks who saw both movies from the total of 60 to arrive at 45 distinct individual moviegoers, making the actual proportion that saw both movies 0.333 (15/45) or 33.33%, an answer not even given as a choice.
The correct answer (whether 0.25 or 0.333) depends of course on the precise framing of the question. In either case Brilliant’s ‘correct’ answer of 0.15 isn’t. While it is true that 15% is 0.15, I suspect that the error is based the incorrect supposition of individuals as percentages, as evidenced in the legend for the graphic, emphasizing how important it is to ask the right questions.
Am I missing something here? Or was this just a fiendish ploy to increase engagement? Thank you for all your truly brilliant content.
Greetings from Moers,
Michael
I don't think there is a star in the black hole. In the video at [5:11] you will see the picture taken by the event horizon telescope. If you pause the video and look at the very center of the doenut shaped (EHT) picture. You will see curved space-time and the black void. The curved space-time concaves down and looks like the edge of a cliff. And looks like the edge of a cave downward, before it goes dark. Also, it looks like a waterfall concaving down. But, I think it's the hot plasma at the very edge of curved space-time, the event horizon. Professor Sabine once said in another video that gravity isn't a force, its curved space-time. Maybe a black hole is like a cliff, like a cave like a waterfall. But its not a force, a force, it's curved space-time.
Im saying this for years. Singularity is just mathematics but not reality.
Uhm, what is the name of the following theory? I'll describe it.
This theory is where black holes are just simply empty shells of ultra-dense matter and light and pretty much everything that can get stuck on them because everything stops due to time dilation at not the event horizon but where time is at a stand-still (or just infinitely slowed) and that's also the reason why black holes can grow by bloating up as a bubble of empty void since it's the shell that grows. The shell itself has a shared gravitational point at the center (like celestial objects of similar mass in binary systems orbit each other around a point and not one or the other) where the gravity of the shell concentrates but also this point has no mass, nothing that would stop it from acting like a singularity, it's just a pure shared gravitational field. Again, an empty shell can also spin as well as orbit around that point at its center. It is similar to the holographic theory which suggests that black holes have all the information plastered on their event horizon but what I'm saying is everything is literally just plastered on the time-stop shell if you will.
This is the most simplistic view I can think of on black holes and I would like to know if anyone is actually pursuing this idea.
Gravastars - I like that name. Never been a fan of singularities, nor a fan of a star collapsing into one (nor neutronium, etc). As my [rejected] FEA analysis, 30 years ago indicated, the highest zone of density is ... in a shell ... not in the center of a star. One correction to make: we DO observe all sorts of stellar ejecta from these massive stellar objects. That said, a single shelled system would be more stable it it's spinning and, when collapsing (after some event that would disrupt it's stability - everything from a collision event to a cooling event), you would observe a good portion ejected matter from the poles (we observe this) as well as ejecta from the implosion rebound. The current model for collapsing stars makes little sense - a denser spherical shell collapsing makes more sense (at least to me). By no means am I implicating stars are hollow in the center, only that the highest density region is not in the center.
This got me thinking on whether or not black holes can have particle shells just like atoms have electron shells. The outermost shell behind the event horizon would have to be photons, the next possible electrons, and so forth, based on the mass/energy levels of said particles. It just might be very orderly instead of chaotic, with exception of the accretion disk.
Not possible, because gravitational acceleration inside the event horizon exceeds light speed (precisely at the event horizon the gravitational acceleration exactly equals light speed: this is what defines the event horizon to begin with). Thus, inside the black hole, any photon or particle would need to move faster than light (in a direction away from the singularity) just to remain stationary. Since nothing can move faster than light, everything that crosses the event horizon thus inexorably falls down into the singularity.
@@Spherical_Cow guess I should have said outside the event horizon instead of inside.
1:54 what are the pieces made of?
Black holes have spin, likely very high spin rates since conservation of angular momentum means anything falling into the black hole brings in some spin which gets faster as it gets closer to the center of spin. The spin results in frame dragging among other things, which distorts spacetime. Also time slows down for the object falling into the black hole. At the horizon, time stops. Like an ice skater pulling in her arms so she spins faster. Black hole spin has a lot of interesting ramifications to the physics.
Time slows down only from the point of view of an external observer outside the black hole; for the object falling in, time keeps on progressing normally. In Relativity, all inertial perspectives are equally valid, so there's no point trying to make absolute inferences.
3:39 it’s not a miracle but think of stars colliding and the difference pops up, gotta be some sort of integration or something. Miracles are like the stars aligning without understanding. We can align our neurons to reflect the differences and predict. It’s hard though when you only have 1 and are trying to find 100 or something though.
The contraction of spacetime should keep the two sides of a black hole adjacent as it 'grows'. It can never get wider from the perspective of something sitting on the edge of the event horizon - it only grows from the perspective of something distant from that horizon. This would keep the density and curvature of the black hole constant to any observer sitting close to its boundary - ie, it would remain an asymptotic slope approaching the horizon no matter how large the black hole appeared to a distant observer.
This would make the horizon physically 'real' as far as an infalling observer is concerned, turning it into an uncrossable firewall. It's still not a truly physical barrier, but you'd certainly notice things happening as you approach it, and you would never cross it due to the asymptotic distortion of spacetime in its vicinity.
From a distance this wouldn't be meaningfully distinguishable from a classical black hole, AFAICT, except that it would not need any particularly exotic mechanisms to avoid information loss or to allow radiation.
I'll admit that I prefer this model mostly because I simply don't see how you can form a classical black hole without violating the Beckenstein Bound, and that appears to be a very hard limit on how our physical reality can behave - nor do I trust any solution that doesn't fundamentally acknowledge the fact that black holes grow according to their surface areas rather than their volumes.
Shells, sounds like an idea in the right direction, in that if gravity has polarity all regular moons, planets, stars indeed all globes and 'black holes' are massive shells with all the action in the protected interior habitat.
I think it was David Deutsch's book where he talks about how the Inquisition used the heliocentric model to calculate planetary motion while still officially proclaiming the geocentric model to be the true reality. This sort of reminds me of that. Sure, you can arrive at the same answer even if you make the system more complicated, but that doesn't mean that's what's going on in real life.
Unless this gravastar hypothesis can make new, testable predictions better than the black hole idea, then I don't see how it's progress. You could just as well say that each black hole is a voracious angel hovering in space and devouring matter in a manner that happens to fit our mathematical models. We're just trading one seemingly impossible concept for another
Using nested black holes - I mean gravastars - to solve the singularity problem doesn't come off as too surprising. If the numbers go to infinity, just move up to a bigger type of number - they're basically just 3d-nested fractions. Just like the set of reals is bigger than the set of integers, even though they're both infinite.
coming from a math background this is so interesting. i have hard time narrowing down my question, how do scientists and physicists know when the math is too good to be true
Some of the aspects of this "new" theory were the basis for a science fiction story I read at least 50 years ago. That a very large black hole could be its own "mini universe" with galaxies and stars - and you could move around within it.
If I recall the science fiction story correctly some "elder" race had created their own super massive black hole "mini universe" as they were not happy with the normal universe and wanted to withdraw until something changed in the normal universe (and they had done things to enable that change). This elder race had the science fiction capability to leave their mini universe black hole and look at the normal universe from time to time to see how things were progressing.
Everything has a singularity if you squash it enough. An object big enough to rip stars apart does not need to be infinitely small. It simply(?) needs to be dense enough for its gravity to trap light.
Are there nice descriptions how merge of black holes happens for different models? E.g. if there is singularity inside what shape space takes when merge happens, do singularities merge too or they keep orbiting inside of EH closer&closer but not merge fully?
How merging of string/m theory fuzzball black holes happens, etc.
The best explanation I have is that a Black Hole is the next step of Neutron Star in terms of density... The more dense a star gets the smaller it is. (Neutron star is smaller than Earth and white dwarf is Earth sized). Therefore the Black Hole is probably a dot.
The problem with using binary black holes as a measuring device means they have a unique problem of having to orbit a barycenter. So they are likely not really acting as black holes until they complete their merger at which point we STOP seeing the gravitational waves which means the black holes are NOT rotating when they're individuals.
This is a closer idea than black holes being singularities, but not quite on the money exactly. You have to observe neutron stars and how they convert into black holes. There is a phantom horizon that then becomes the event horizon. This indicates that there is a phasing of neutrons into a new form of matter forming at the core. It is likely that this matter is so perfect and powerfully magnetic and dense that it causes the 100% gravity line on the surface to pass the surface of the mass causing a lensing effect. Now it is likely that there are layers to this mass but unlike a star its core is not the main producer of energy rather the outer later becomes 99.999% pure cartesian energy giving it the appearance of a mass without magnitude. And this layer essentially preserves the mass from decaying rapidly. In turn it actually decays slower than anything we know in the universe. But once decayed you likely are left with a pure solid mass of let's say, moscovium being that this the highest element possible for stabilization with a perfect molecular structure making it likely the most magnetic and strongest metal in the universe.
One of the few things we can learn from history is that if there is a mathematical solution of gr then it exists somewhere. Iirc schwarzschild solution was initially discarded on the basis of being unphysical
It was unphysical. Schwarzschild was solving for a non-rotating star. Of course it had an infinity at the center, but even Newton's equation had that infinity, but we knew all of the mass of a planet or star was not actually at the center, so we knew this was unphysical. Einstein and Schwarzschild noticed the odd radius, but since most of a star's mass would be outside the radius, clearly it was some sort of mathematical artifact. Neither of them proposed that there could be a new type of object where all of the mass was inside the radius.
Have I actually heard the argument that "physicists have not yet observed impacts on the surface of a black hole/gravistar"?
However, there is currently no Tesekop that has the necessary resolution. Strictly speaking, no black hole/gravistar itself has been observed yet, only secondary effects. That's why all solutions to Einstein's field equation are always just theories of what could exist, but not yet confirmed reality. A difference that has been often forgotten lately.
There's no better place to grow your knowledge than Brilliant? Not true! Stay scientific, dear Sabine.
Wide Sabine is going to give me nightmares 😭 excellent video as always 💜
I don't know this does seem to have some appeal, it seems to support the idea of the preservation of wave-particle duality. Is their a double slit experiment that could be performed for a stream of black holes?
1:56 kinda shows how the integration happens, that difference may be sharing and that’s why it’s easier to slip in. Like the earth and the center of our universe or as we get deeper in the ocean and the integrated dif of all the things in it do contribute to the overall weight like even fish reveal that difference while maintaining the things they have inside or their differences. Like a neuron, keeping its shape and connections, but changing. A greater change can cause a greater difference just as the inverse but it’s what is in the 3rd portion that connects the two but it’s actually many connecting. Our neurons rep and connect to reflect. So it’s like, if another black hole synced up kinda like mag fields then the differences can be intertwined without the tearing apart. Exchanging differences through the connection. Similar to humans going to another planet we can go but the differences may be too great and cause a reflection of death or destruction or even the opposite and be amazing and integrate well.
this analogy is pretty cool, as it could illustrate that the universe is just layers of blackholes superimposed on each other like russian nesting dolls. but just how mindbogglingly massive would such a layer have to be for us to enjoy relatively coherent existance?
like ripples in a pond, each ripple is its own universe with the edge of its wave its own end to the observable uiverse. which is for its sake and reference, only the parts of the ripple they are riding on that they can see. cool. cool story bro.