I’m not an astrophysicist, but that ends up being the weird perception thing about them, right? Mostly they’re like a star of the same mass, and then a few will get really big and be at the center of a galaxy, but the perception is that of a natural disaster.
Big ball of plasma in the center of the solar system that will definitely eventually explode and wipe out anything left alive on any surrounding planet? NBD. An object of the same mass but it’s smaller so it doesn’t shine? People picture it as being more immediately violent for some reason because the “light can’t escape” thing sounds so wild.
Yeah, black holes in media where they are depicted as a giant space vacuum cleaner is a big pet peave of mine. Unless you get really close, nothing is remarkable about the orbital mechanics of a black hole. The equivalent mass star would have burned you up at a much further distance than the gravity starts to become noticeably wonky.
It’s a shame that writers focus so much on the gravity and neglect accretion disks and astrophysical jets which do extend large distances and are visually stunning as well.
If we ever invent FTL someone is gonna make a black hole bomb.
It’s already invented, just put enough mass in too little space. Don’t need a star like mass, any will do if you can compress it enough.
also the way they bend light, a proper physically simulated depiction of a black hole is so fucking cool because it just kinda intuitively looks like it’s so heavy it’s bending spacetime around it!
To be fair I think “light can’t escape” thing really just is that wild, it’s pretty captivating. The idea of it being the death of a star, one of the most important things to all life we know about, only adds to that sense. Stars are massive billion-year explosions, yes, but they also bring warmth and light and beauty. Black holes are the death of all of that, even if it’s not technically more dangerous from the same distance
It’s not that light can’t escape that is scary it’s that the future of anything passing the event horizon changes to eventually end up in the singularity. Black holes are not just death, most of the things in the universe are death to us, black holes are literally the end of time.
Or they are passages to other universes.
https://en.m.wikipedia.org/wiki/Wormhole#Einstein–Rosen_bridges
Still the end of time for our universe, like it mathematically is. And we haven’t found any white hole in our universe yet despite it probably being much easier than finding black holes or most of the other stellar objects.
Could the big bang be a white hole? And doesn’t it make sense the wormhole kind of meaning you “wait” in the black hole until the end of the universe and the beginning of a new one as it will look like time slows down for someone approaching a black hole for an outside observer but not for the person entering.
I don’t think we know how the end of the universe even from outside of the black hole would look like. If I remember correctly at some point even black holes may evaporate due to Hawking radiation.
As for the big bang being a white whole, there are a lot of problems. Like it would mean the universe started at one point in space and that’s the opposite of what we see that the universe started everywhere.
The true death of that is more depressing than torturous: Heat Death.
Especially since we still don’t know how information preservation works in a black hole. There are ideas yes but we still aren’t sure if any of them are even right.
Big ball of plasma in the center of the solar system that will definitely eventually explode and wipe out anything left alive on any surrounding planet?
The sun isn’t heavy enough to go supernova. (Unless it has a companion, but there’s no evidence of one so far.)
It will still expand and shed enough stuff to effectively blanch whatever part of the solar system it doesn’t actually engulf, though.
It doesn’t even have to go supernova to kill everything, which is kind of the point.
Pop sci-fi seems to be fond of intermediate-mass black holes (EG Interstellar, Star Trek StrangeNew Worlds), and for something kinda the size of a star, they are “scary.”
In other instances (like in TV Foundation), a close orbit to the accretion disk is a source of suspense.
And then there’s the “stealth” aspect. Stellar-mass ones and below are very small and (potentially) quiet for something with the mass of a star, eg easy to stumble upon.
And in some very advanced universes (eg the online Orion’s Arm), even with “hard” sci fi, swimming through a star’s nuclear plasma is totally doable. But a black hole is an impossible boundry of physics, and an particularly extreme object useful for astroengineering.
They are like stars in the sense of orbital mechanics.
But a star can be completely understood by the laws of physics we know. While a black hole breaks our understanding and we have no idea what’s going on in there.
It’s the fear of the unknown.
I don’t know. Isn’t it rather that they were predicted by the laws of physics we know (or got to know with Einstein) and everything about them can be fully described and is known by our current understanding of these physics?
But I get what you mean. They are a symbol of the weird counterintuitiveness of the theory of relativity.
Sort of. They were predicted by Einstein theories. But in a way so absurd that it was supposed to be just a faulty part of the theory when you push it to a extreme. Basically the “infinite collapse” that occurs and that should put all mass in a infinitely small space.
That cannot be true, it collides with quantum theory.
We have observed the space surrounding black holes, and that is spot on with the theory. But we know nothing about what occurs inside them. We don’t know the density of the singularity, it’s structure, how that matter behaves at quantum levels. We know nothing about that.
Once you enter a black hole is not only that you would be torn to pieces and pieces to atoms, we don’t even know if atom structure would even exist in there. Maybe even boson-fermion structure doesn’t even exist inside a black hole.
Tell me you don’t understand black holes using a lot of words.
As far as gravity goes they are equivalent to the star that they collapsed from and just as deadly.
The difference is that you can get that much closer before “impacting” with it, but you and superman would be fucked pretty much at the same distance from it.
And I think you need a lot less than 300 writers to conjure an idea that leverage our fantasy in more and better ways.
And an infinitely dense point in spacetime doesn’t necessarily exist: it’s just what general relativity predicts is at the center of a black hole.
The last time our physical model of the universe predicted an infinite value, we ended up discovering new physics eventually (the ultraviolet catastrophe). (Edit: ultrasound was a typo).
I think you’re referring to the ultraVIOLET catastrophe
yeesh, what was the ultrasound catastrophe then?
That whole comment was a struggle to type on my phone at the time because the screen was wet, so at the end that one slipped though.
still, kind of funny wondering what an ultrasonic catastrophe might have been
It’s what OP’s parents call the first day they saw him.
aw thats kinda mean
And an infinitely dense point in spacetime doesn’t necessarily exist: it’s just what general relativity predicts is at the center of a black hole.
If the singularity at the center of a black hole didn’t exist, and was just extremely dense instead, would all of the other properties that we know is true about black holes be able to exist? For example we know that Sag A* and that one other black hole we ‘imaged’ give off no light, would that still be possible without a singularity?
In General Relativity, the way to get gravity so strong that not even light can escape is with a singularity: a point of infinite density. So, either this infinity physically exists, and maybe we’ll understand how better, or General Relativity may be incomplete: a model that works well most of the time, but doesn’t represent reality correctly at the extremes of heavy mass and small space.
Or at least that’s how I understand it. This has more info: https://physics.stackexchange.com/questions/18981/why-singularity-in-a-black-hole-and-not-just-very-dense#18987
This is similar to the ultraviolet catastrophe. Physicists predicted black body radiation using their current physical models, with high accuracy at low wavelengths of light, but at high wavelengths, the predictions diverged towards infinity, which disagreed with measurements.
(Source: Wikipedia)Breakthroughs in quantum physics later reconciled theory with measurements.
One big difference with black holes is we cannot yet measure the actual density in the interior of the black hole. We just have the prediction that there is a point of infinite density.
Any physicists around here may have a better understanding than me.
I appreciate your detailed answer, thank you for taking the time :D
Nothing you said about black holes really contradicts what they were saying? Even if a star and black hole can have the same gravity, there is still a shell of space that once you pass you cannot ever return. I’m sure Superman could go into a star and come back out, not so much with a black hole.
No. You can’t ever get out of a lot of shit.
From a common star, if you can make your mass somehow be almost 0 and your speed being almost c, you can get out.
I mean, the gravitational gradient is much higher. To me this kind of sounds like saying “there’s nothing that special about a 10 watt laser, an LED lightbulb puts out the same amount of light”, but a 10 watt laser is enough to instantly and permanently blind you.
Its true that there’s nothing that special about orbiting a black hole, but I think its not really logically inconsistent (inasmuch as a superhero can be logically consistent) to say “even if superman could survive dipping into a sun he probably wouldn’t be too happy if he stuck his arm into an event horizon”.
I knew before coming into the comments there would be a pendatic with this argument
And you were right! Kudos to you!
My understanding is that the singularity is not proven to exist and many physicists believe it is an artifact of our incorrect understanding of the physics involved.
Well, what exactly is inside the event horizon is unproven because we cannot possibly look. All of the rest of the physics seems to check out, though, and we know that there are things out there that behave just like our models of black holes predict. It’s an incomplete understanding rather than a necessarily incorrect one. If it is something else, it’d have to be something that looks more or less exactly like a black hole to an outside observer
I would think an object of extremely high density could be difficult to distinguish from a point of infinite density, especially given the nature of the event horizon.
I’m not saying the models are definitely wrong but usually when one of your terms goes to infinity it is a good reason to be skeptical.
All of the rest of the physics seems to check out, though
What is the entire problem, because all of the rest of the physics don’t get you coherent answers around a black hole.
In one, you mean? They get you perfectly fine answers around one
At the close vicinity where they don’t actually agree if it’s inside or outside.
There’s lot’s of issues with current physics, mostly in cosmology. String Theory was partly invented to describe the interior of a black hole. The characteristics of the Higgs field are still unknown. Gravity is still not unified with the other forces, despite appearing to couple with everything. Our current best models for the formation of the universe predict huge amounts of invisible matter, and we have no idea what that could be, from new particles to microscopic black holes formed in the first nanoseconds of the universe, to reinterpretations of relativity. Those same models also predict that out universe is dominated by strange energy inherent to space itself, which has no basis in the Standard Model at all. I wouldn’t call these perfectly fine answers.
And even if the nature of the interior of a black hole what the only issue, the final part of physics we haven’t explained, I would say we’ve thought that before. About a century ago, the scientific community though they had mostly solved physics. The last big question was why ultraviolet light didn’t extend out to infinite energy as predicted. Then photons happened and we discovered quantum physics.
All of the rest of the physics seems to check out
If the whole universe comes from the singularity and you need just a tiny fraction of it in a limited space to create a black hole, why the universe even exists and even more so, it’s expanding each day faster?
The theories on why are a fair bit beyond my knowledge of physics, but I do know that they’re not necessarily the same kind of singularity. Inside a black hole (assuming our models are correct), spacetime curvature goes towards infinity. At the big bang, there may not have even been spacetime as we see it in our current universe, or whatever causes the expansion of spacetime may have been so powerful that it caused the earliest spacetime to not curve despite all the gravity
Different things.
The singularity of a black hole is located in space.
The initial singularity of the big bag happened “everywhere” the whole universe was supposed to have infinite density.
The mass of the black hole is finite. It’s very dense but it have a quantifiable amount of mass.
For the big bang the mass was also infinite as far as we know. Everything was singularity, every “energy” in your body was part of that infinitely large singularity. Not only everything but everywhere. Where you sit there was singularity during the big bang. As far as we know every single point in space was part of the initial singularity. We don’t come from a single point that exploded towards empty space. Expansion is more like the surface of a balloon. Maybe it’s better to think of it as stretching rather than expanding.
Beyond that we don’t know much about both, there are barriers which prevent direct observation of both.
The expansion of the universe is a completely different matter, as it’s not only expanding, it’s expanding faster that out gravitational models predict, like the universe is not only “ignoring” black holes, it’s expanding despite all observable matter, and all untraceable matter (dark matter), and it’s expanding faster and faster driven by an unknown phenomenon we call “dark energy” for giving it a name, because we have remotely not idea of what’s going on.
“marauding black death wrapped in a spherical gradient of tortured space time” is a great title for a progressive rock or technical death metal song
“In a spherical gradient of tortured space time” is a great title for an ambient or very slow.and moody electronic music album.
Why is nobody talking about how
marauding black death wrapped in a spherical gradient of tortured spacetime
is such a fucking cool sentence
I’m just excited to see people having knock down drag-out fights about how scientifically accurate tumblr prose is on a comm that’s not my responsibly to moderate!
I suppose cosmic horror elder gods like Cthulhu and such are not all that far removed from the idea of a black hole. Particularly the ones that are less involved with Earth than Cthulhu is. Nobody is ramming a black hole with a fishing boat. But the early writing on them was done at about the same time as a lot of the foundational theoretical work on black holes (not the earliest stuff but I can believe that the writers didn’t know about it)
Yeah, Azathoth fits the bill in many ways.
Also, extremely pedantic note - black holes were predicted by looking at what happens in the math at extreme densities, long before black holes were actually observed in space
And some of the scientists who worked on those early calculations assumed it meant the physics was incomplete!
If I remember Lovecraft correctly the whole idea was that human mind can’t comprehend such things. And black holes fit very nicely.
black holes seem pretty comprehensible to me? like there’s a lot of math and programming that’s way harder to wrap your head around
Teachers: You can’t divide by zero.
Nature: Hey guys, check this shit out.There are math models where dividing by zero makes sense. It’s just that those models don’t suit our world for now.
Now get this: some scientists think black holes might have hair.
Everything was hairy back in the 70’s.
But can you comb it all into the same direction?
yes because they have a bald spot due to high testosterone levels
Just FYI Superman has survived a black hole because the plot demanded it.
graph function singularities exist as physical features in our world
Do they, though…?
As I (mis?)understand it, as a massive star begins to collapse, getting denser and denser, the gravitational gradient gets steeper and steeper… and time (from the perspective of an outside observer) gets slower and slower… to the point that, from our point of view, the full collapse (or maybe even any collapse below the Schwarzschild radius?) hasn’t happened yet, and won’t happen until the extremely distant future, beyond the end of the universe…
So, in that sense, from the point of view of “our world”, no singularities (except possibly the big bang) would ever exist (yet), all of them being censored not only by event horizons, but by being shoved into the perpetually far future, beyond time itself…
And, speaking about event horizons, isn’t the whole “light isn’t fast enough to escape” concept a misinterpretation of sorts…? As I (again mis?)understand it, it’s not a matter of speed, but of geometry… The way space-time is twisted in such a gravitational gradient, once you get past the event horizon there are no longer any directions pointing towards the outside.
Which is another from of cosmic censorship (or a different effect or interpretation of the above), preventing anything inside the event horizon from causally interacting with the outside universe…
So, if these singularities are hidden beyond sight, causally, visually, and geometrically isolated from the rest of the universe, and perpetually shoved into the far future… can they really be said to exist in our world…?
(Of course there’s always the big bang, but we can’t really observe that one, only its effects, and it’s not necessarily exactly what the original post was talking about anyway…)
I think you explain it pretty well, but one thing to add. Due to the General Relativity and thus spacetime it is actually not directions that all point toward the singularity, but as soon as you cross the event horizon all of your future becomes the Singularity, not as a point in space, but a point in time
https://plato.stanford.edu/entries/spacetime-singularities/lightcone.html
This points at that, you would also need to be able to travel faster than light and that would make you time travel backwards in time
Fun fact: the big bang was not a singularity.
That was an interesting article. Thanks for sharing!
The CW flash can escape from a black hole
GOOD point
Plus, black holes may do contain universes. This year there was some evidence pointing that our universe is actually trapped inside one… ref: https://futurism.com/universe-trapped-inside-black-hole
I heard it more like, the fact that our universe is expanding faster than light, means there are parts of the universe we can never reach, even at light speed, which is mathematically identical to the event horizon of a black hole, which not even light can escape from. There’s not a singularity at the center of our observable universe, though.
I heard it more like, the fact that our universe is expanding faster than light, means there are parts of the universe we can never reach, even at light speed, which is mathematically identical to the event horizon of a black hole, which not even light can escape from. There’s not a singularity at the center of our observable universe, though.
Just to add to this… It’s not like there’s an event horizon like with a black hole. It’s just that in the amount of time it would take the light to reach us, there will have been more space “created” than the distance the light was able to travel. For someone living near the edge of our observable universe, there’s nothing strange happening. In fact, we’d be at the edge of their observable universe, the edge of their “event horizon.”
There’s not a singularity at the center of our observable universe, though.
Well, er, how would you know?
Perhaps the space inside the event horizon is so large, and the distance to the singularity so great, that the expansion we observe from our reference point appears uniform.
I know there is no singularity at the center of our observable universe as we are at the center of our observable universe and the Earth has not been destroyed by a singularity.
That’s sounds exactly like what someone trapped inside a singularity would say.
I think someone trapped inside a singularity would be too dense to say anything :)
To be fair you require time to become too dense and time doesn’t make sense in singularity. Perhaps you are on your way to become too dense.
Hmm, but what if the Earth has not been destroyed by a singularity yet?
We are at the center of what we can observe, obviously, but assuming that everything (including what we can not observe) is within the event horizon of a singularity then what we can observe may all be experiencing the same (relative) spacetime curvature and is apparently “expanding” because it is accelerating as it falls deeper into the singularity.
I’m kind of thinking of the classic spacetime expansion demo of dots on the surface of a balloon, extended into 3(+?) dimensions… the singularity (the balloon) is expanding as we (and everything else) are drawn further into it, resulting in the objects we can see (the observable universe) appearing to accelerate away from us. The actual center of the singularity is so far away that we can’t observe it, and the acceleration appears (locally) uniform to us in the same way that the surface of an infinite-radius sphere would appear flat.
There’s probably some obvious physics reason this doesn’t work in reality, but I don’t know what it is.
That is certainly an interesting hypothetical hypothesis, if you can think of any way to falsify it (I can’t), I’m all ears!
Well the reason we know is because we’re at the center of the observable universe and Earth isn’t a singularity.
Idk, I don’t think most scifi pushes the envelope of what we can imagine, rather it provides a convenient escape to galaxies less incomprehensible than the bewilderment of earth where the author can make a point about spacewar and unstoppable mindless empires.
shrugs
Scifi (like any other genre) needs to continually reaffirm its association with creativity, not assume because paper thin character types are fighting spacewars for feudal empires and space corporations that it counts as pushing the envelope of our imaginations.
/end side rant
I’ve heard that ‘our reality is made of math’ before. Does this mean that we do in fact live in a simulation, even if that simulation wasn’t necessarily programmed by ‘higher dimensional’ beings?
If that is the case, could we conceivably ‘hack’ the universal code and unlock cheat mode?
We don’t need to “live in a simulation” for “our reality to be made of math”. Math could very well exist outside of anything, as a formal concept. This is the old debate asking whether math is invented or discovered. If it is discovered, then it can exist without any reality, as a pure abstract concept.
It’s confusing. I don’t understand what the difference is between something which is made of ‘a pure abstract concept’, specifically math, and a simulation- which is also made out of math.
I’m not saying it’s something ran on a computer somewhere, just that the abstract concepts that make up our universe, if it is “made of math”, clearly has rules that it obeys- like the speed of light in a vacuum or the other constants. Which would seem to be analogous to parameters in a more traditional simulation. If ‘math’ is something that exists independent of sentient beings, couldn’t whatever that is be the ‘thing’ that the ‘simulation’ is ran on?
I guess where I’m getting hung up is the idea that the universe can be ‘made of’ something that has no ‘reality’. Am I just misunderstanding what it’s meant by ‘made of math’? Like even if math is ‘discovered’, how would that be any different than us inventing it, if it exists ‘without any reality’?
To be fair, there is lots of stuff I don’t understand, but I am trying- go easy on me.
I was being cheeky about the ‘cheat mode’ thing (unless it’s real then I’m in).
I feel like there is a misunderstanding in this thread.
The universe is described by math. Math itself is also very fundamental though.
However even the Singularities are disputed and generally not liked by physicist. We try to find other explanations for how black holes work (lots of papers on this). Moreover, we never really have a singularity, but ringularities, as all black holes rotate changing the singularity to a singularity (they probably also have a charge but that is a different matter).
And on the other hand, if you are a follower of the simulation argument (I know a few physicists that are) there are also counter arguments against this (which I believe are more likely).
Don’t worry, it’s confusing for everyone (including me), this is a very fascinating, yet forever (I think) out of human reach, question.
What I was trying to say is that our entire universe/reality could be like a “conway game of life” : In this “game”, every step is fully determined by the previous one, in order to know what the next step is going to be, we human run a simulation, on a computer, or on paper or whatever… But is it to say that all the future steps don’t exist before we “simulate”, we could consider that, since they are all predetermined, the steps exist even if we don’t know what they are, they could simply be. Just like the number “1” could be a fundamental truth, that could exist outside of any universe.
If mathematics is discovered rather than invented, then that would imply that it exists without anyone or anything, an undiscovered theorem would still be true. The universe could be a big mathematical game of life that exists because it cannot be any other way, and that is fully determined. Then again this could also not be. Who knows !
Stephen Wolfram is a very controversial physicist, who explored those abstract and unprovable concepts, even though his statements should be taken with a grain of salt, it is nonetheless very interesting philosophically: he came up with the concept of the ruliad and the idea of computable irreducibility, if you want to explore these philosophical questions you can look it up, he has a few ted talks and YouTube videos where he details his thought. I cannot stress enough that he should be listened to with extreme skepticism, this is not science “yet”, and it might never be.
I appreciate you taking the time to reply in detail, thanks :)
I’ve never heard of the Ruliad before- I will definitely look into that.
He bathes in the black sun
The Beast and his armies shall rise from the pit and make war against God.
He is awake
And you will worship him
