98
Hang on, I was under the impression nobody actually thought singularities existed, only that our current math and physics isn't developed enough to get any reasonable results in such extreme places?
Nobody who's informed believes that the center is infinite, the general public on the other hand has been told the center of a black hole is a point of infinite density by 'experts' for nearing a century. It's the same mistranslation that happens when a lot of science is published in media, it's easy to just say what an expert knows but it's a lot harder to explain it well. The expert knows TONS of nuance on their subject while the rest of us don't have nearly enough time to become as informed as they are.
Doesn't the math say that it is a point of infinite density, and we know that can't be true, but are at a loss to explain it?
Or did I really get it wrong?
You are not wrong. So I am not an expert in this area. My understanding is that we get different answers depending on what branch of math/physics you're using. Relativity theory says it is infinite, quantum theory says it isn't. The consensus of most experts in this field is that the center of a black hole isn't infinite, but that's based more on intuition than actual evidence. So the real answer is we don't know, but the educated guess is that it is not infinite.
Maybe. If so, it would be like the ultraviolet catastrophe
For the general public, as you call it, a black hole is giant fixed vacuum cleaner in space, and infinite could as well be a chineese word. And it's not a mistranslation, it's that it doesn't matter.
It's not that maths and physics aren't developed enough, it's that we don't know. General relativity is not wrong, at best it is inaccurate, and we have no way to prove it yet.
It's like newton's gravity : it's not wrong, it's inaccurate outside of some conditions.
Welp, this is my not-going-to-understand-anytime- soon article for the week
A singularity is the single point mass at the center of an ideal (Schwarzschild) black hole. But mathematically, that can only happen if the mass that forms the black hole isn't rotating. In reality, all the mass in the universe is moving around, because mass is not distributed uniformly, so gravity is pulling stuff around in a big mess. So when a black hole forms, it's definitely a rotating (Kerr) black hole.
A rotating mass has different gravity than a non-rotating mass. Not by much, but when you've got the enormous mass of a black hole, it becomes significant. This causes objects "falling into" a black hole to "miss" the point at the center, and form more of a cloud during spaghettification.
The article is fairly accessible if you sit down and read it.
Honestly, inside the event horizon, everything stops making sense compared to our day-to-day experiences. The immense gravitational forces distort space and time. It doesn't really make sense to think about objects remaining intact as recognizable objects once they cross the event horizon.
I read it and understood the setup in the first section that you're paraphrasing about ideal black holes with the 1963 kerr advance and the orbits, but don't know if I understood the whole reasoning behind the thesis of the article in the later sections of the article, that singularities don't exist.
If you scroll past the opening explanations of ideal black holes, Kerr later asserts that because of the elliptical orbits of matter and light trapped inside the inner event horizon due to black hole rotation, there's no central singularity and just an inner cloud of matter perpetually traveling in elliptical orbits. I think this is the spaghetti you're talking about.
Is that assertion of the structural difference in practical black holes the whole point of the article?
I love how "there is no center of a black hole" was the ridiculous part of the math, not that they turn you into spaghetti if you touch them.
Can you ELI5 this notion of a FALL or even what affine geometry is broadly speaking? That's where the author completely lost me.
Not really sure about it, but as I understand it, affine geometry can be translated as linear geometry. Think euclid geometry in a 2d plane. In this black hole, I think it means that a particule behind the event horizon will go straight to the center. So every trajectory behind the hoziron is a line that goes to the center, and this center is the singularity.
So spaghetti in orbit? Band name, I call
There's already a “religion” 😅, you might have to deal with them concerning your band 🤣.
By the way, they typically wear colander over their head…
Seems like Roy Kerr did not watch Star Trek. Otherwise he would know that singularities exist and also that it is possible to punch through the event horizon, to free yourself after your spaceship gets pulled into one.
Obvious /s
this post was submitted on 05 Dec 2023
98 points (100.0% liked)
Science
13200 readers
15 users here now
Subscribe to see new publications and popular science coverage of current research on your homepage
founded 5 years ago
MODERATORS