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!
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
all of your future becomes the Singularity
There is some small burn-off Hawking radiation that escapes and gradually reduces the mass (and information content) of the black hole. Some of that would be you.
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.
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%E2%80%93Rosen_bridges
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.
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.
Keep in mind that all the cliches about black holes are about non-rotating black holes, which don't exist in reality. In reality, a spinning black hole has a ring singularity, not a point, and behaves much weirder and even less intuitively than the hypothetical non-rotating counterpart as it smears out spacetime into taffy.
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).
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.
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)
Just FYI Superman has survived a black hole because the plot demanded it.
Teachers: You can't divide by zero.
Nature: Hey guys, check this shit out.
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
that's the fun part, everything is always falling!
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