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No, we can not. We can't even simulate a hydrogen atom, which is far simpler. For that matter we can't simulate a single proton either. See: https://www.quanta
by ars 3y ago
No, we can not. We can't even simulate a hydrogen atom, which is far simpler.
For that matter we can't simulate a single proton either. See: https://www.quantamagazine.org/inside-the-proton-the-most-complicated-thing-imaginable-20221019/ https://www.quantamagazine.org/inside-the-proton-the-most-co...
(Unrelated but this is why I don't believe singularities exist in the universe - we don't know enough about quark degeneracy pressure to know if it's actually possible for a star to collapse - it's possible the quark pressure keeps the matter from compressing.)
- AtlasBarfed 3y agoThey're just quark stars with an event horizon?
- ars 3y agoNo event horizon, just incredibly powerful gravity.
- AtlasBarfed 3y agoSingularity or not, strong enough gravity produces the event horizon, does it not? It's the boundary where escape velocity exceeds the speed of light?
- addaon 3y ago> it's possible the quark pressure keeps the matter from compressing Why are you more comfortable with infinite pressure forces than infinite densities?
- AnimalMuppet 3y agoIt wouldn't have to be an infinite pressure force - just enough to keep a finitely-sized collection of quarks from collapsing further.
- addaon 3y agoFinite, but bounded only by the mass of the visible universe.
- codethief 3y agoYou don't need fermions to form a black hole. Bosons (in particular: photons) work, too [0, 1, 3], as do gravitational waves [2], so Pauli pressure is not a convincing argument against singularities. [0]: https://en.m.wikipedia.org/wiki/Kugelblitz_(astrophysics) https://en.m.wikipedia.org/wiki/Kugelblitz_(astrophysics) [1]: https://arxiv.org/abs/1408.2778 https://arxiv.org/abs/1408.2778 [2]: https://arxiv.org/abs/0805.3880 https://arxiv.org/abs/0805.3880 [3]: https://arxiv.org/abs/1105.5898 https://arxiv.org/abs/1105.5898 (building on [2])
- ars 3y agoIt's pretty unlikely that any exist though. Which was my point. Although I have a side question: Imagine three streams of light, each 1/3 the density needed to make a black hole, traveling at a slight angle from each other, and then meeting. The moment they meet they are a black hole. How fast is that black hole moving afterward in order to concerve both momentum and energy? You'll find the answer is: The speed of light. There are clearly unsolved issues with Kugelblitze.
- samus 3y agoThe plural of "Kugelblitz" is "Kugelblitze".
- btilly 3y agoDo you have a source? When I do a naive version of the calculation I find it is slightly below the speed of light, with the amount below depending on the angles between the beams. The full calculation is beyond my skills.
- ars 3y agoYah, I errored in thinking 3 beams would negate that, but it wouldn't, it would be just below, as you say. But you have another issue: Even if you are just below the speed of light, most of the mass would become relativistic mass (and relativistic momentum), with almost no rest mass. But there's a postulate that only rest mass can make a black hole, and relativistic mass doesn't count. (Because otherwise you could travel fast and see inside the black hole.) So we are left with a contradiction.
- namibj 3y agoThere's also the continuous collapse theory that assumes you start with a mostly classical gravity system and then just reach a runaway where the internal pressure can't keep up anymore, followed by the space time well getting rapidly stretched towards beyond an event horizon, making it so that due to finite propagation speed of this concentric ripple in space time, the further in you start, the sooner the distance left to the first spacetime outside for a fresh photon increases with time passing instead of decreasing, because the space time between the photon and outside continues to stretch fast enough to cause "beyond-infinite" red shift.