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Interpreting various equations from my limited knowledge of such a discussed area, I've come up with this: Hawking radiation makes a black hole lose mass, henc

by lloeki 14y ago

Interpreting various equations from my limited knowledge of such a discussed area, I've come up with this: Hawking radiation makes a black hole lose mass, hence diminishing its Schwarzchild radius. The Schwarzchild radius came up because it's a singularity (in the mathematical sense) in a solution to Einstein filed equations. The same way matter collapses onto itself up to creating such a singularity and being encompassed into the now existing event horizon, as soon as there is not enough mass to sustain the singularity, the event horizon vanishes, hence the remaining matter "pops" back into our sight. You could view it otherwise with a thought experiment: take particles out of the black hole one by one. Each time it will reduce the mass and maybe the radius. At some point the mass/radius ratio may not be small enough to hold light and the bubble bursts in plain sight as the event horizon breaks down. In such a thought experiment, the worst case would be that the black hole would require every single particle but one to evaporate (unless you assume a single particle could be a black hole in itself). An interesting back of the envelope calculation is computing the mass contained in a Schwartzchild radius of Planck length (the size at which quantum effects take over). l_P = sqrt(hG/c^3) r_s = 2Gm/c^2 hence m = sqrt(hc/4G) = 1.0882546265651108e-08 kg which is a bit more than 1e22 electrons sitting at a position 1e-15 smaller than a single one of them.

Morg 14y ago
Black holes are just a whole lot of matter stashed in the same place, the only "strange" part is the effect of extremely intense gravity, like deviating photons to the point where you never receive them, etc. In effect the hole isn't even black it's just an effect of all light that could come from that direction being warped around it. As has been seen before with twin stars, when photons pass near very heavy objects like stars, it happens that they will have a curved trajectory, in the case of twin stars two trajectories, one left and one right of the star, causing two images of the same star. That's with a very light object compared to a blackhole. With blackholes, it simply has a curved trajectory, that orbits/crash into the black hole, thus sending absolutely no photons our way, thus no light, thus black. There is absolutely nothing mysterious about black holes, just edge effects because they're not even remotely comparable to what we can readily observe, and most closely related to the aspect of physics we understand the less : gravity. Schwarzchild radius in this case is a cool term, but it's a very simple concept, it's just the distance from the center of an object at wich photons start having non-collision trajectories (i.e. some light escapes if it has the right trajectory). http://en.wikipedia.org/wiki/Schwarzschild_radius http://en.wikipedia.org/wiki/Schwarzschild_radius Essentially. nothing particular and in fact there are event horizons inside existing matter, just that noone cares since it's inside. If you remove mass from a black hole it gets bigger, nothing new or special there, it would work the exact same way with our sun too, as when it will become a red giant, far bigger yet much lighter. If you keep removing mass from your black hole, at some point it's radius crosses it's schwarzchild radius and tadaam it's a star instead .. still the same object though. About the hawkins radiation, I have no clue, but whatever they are they seem to be considered minimal compared to the influx of mass/energy from galaxy collisions, galaxy eating and all that.
astrodust 14y ago
Is there anything to preclude there being an ultra-massive particle that might be able to cause a singularity by itself? The particles we observe today exist in a relatively low-energy environment. Whatever's going on in the furious intensity that is the inside of a neutron star that's on the edge of becoming a black-hole could be quite spectacular in comparison.

by lloeki 14y ago

Morg 14y ago

Black holes are just a whole lot of matter stashed in the same place, the only "strange" part is the effect of extremely intense gravity, like deviating photons to the point where you never receive them, etc. In effect the hole isn't even black it's just an effect of all light that could come from that direction being warped around it. As has been seen before with twin stars, when photons pass near very heavy objects like stars, it happens that they will have a curved trajectory, in the case of twin stars two trajectories, one left and one right of the star, causing two images of the same star. That's with a very light object compared to a blackhole. With blackholes, it simply has a curved trajectory, that orbits/crash into the black hole, thus sending absolutely no photons our way, thus no light, thus black. There is absolutely nothing mysterious about black holes, just edge effects because they're not even remotely comparable to what we can readily observe, and most closely related to the aspect of physics we understand the less : gravity. Schwarzchild radius in this case is a cool term, but it's a very simple concept, it's just the distance from the center of an object at wich photons start having non-collision trajectories (i.e. some light escapes if it has the right trajectory). http://en.wikipedia.org/wiki/Schwarzschild_radius http://en.wikipedia.org/wiki/Schwarzschild_radius Essentially. nothing particular and in fact there are event horizons inside existing matter, just that noone cares since it's inside. If you remove mass from a black hole it gets bigger, nothing new or special there, it would work the exact same way with our sun too, as when it will become a red giant, far bigger yet much lighter. If you keep removing mass from your black hole, at some point it's radius crosses it's schwarzchild radius and tadaam it's a star instead .. still the same object though. About the hawkins radiation, I have no clue, but whatever they are they seem to be considered minimal compared to the influx of mass/energy from galaxy collisions, galaxy eating and all that.

astrodust 14y ago

Is there anything to preclude there being an ultra-massive particle that might be able to cause a singularity by itself? The particles we observe today exist in a relatively low-energy environment. Whatever's going on in the furious intensity that is the inside of a neutron star that's on the edge of becoming a black-hole could be quite spectacular in comparison.