thinking about the universe is already traumatizing
Where does it end? How are we floating? What if we fall? Where does it come from?
I don't think about that a lot so it doesn't give me anxiety
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
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'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).
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.
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).
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.
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.
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.
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.
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
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.
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%E2%80%93Rosen_bridges
Just FYI Superman has survived a black hole because the plot demanded it.
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.
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.
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).
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
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".
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
"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
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)
The CW flash can escape from a black hole
GOOD point
Now get this: some scientists think black holes might have hair.
But can you comb it all into the same direction?
Teachers: You can't divide by zero.
Nature: Hey guys, check this shit out.
A place for majestic STEMLORD peacocking, as well as memes about the realities of working in a lab.
Rules
This is a science community. We use the Dawkins definition of meme.
