Questions tagged [black-hole]
Questions regarding points of extremely high mass density, which creates an extremely strong gravitational field from which light cannot escape.
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What is the best catalog of black hole candidates?
I posted this questions in Physics stack:
"I am searching for a catalog, list, database, etc. That should show astronomical observations of known black hole candidates. I am primarily interested ...
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Why does c show up in Schwarzschild's equation for the horizon radius?
The equation of the Schwarzschild radius is really simple, just twice the mass over $c^2$ (times a unit conversion constant that goes away in natural units).
$$ R = \frac{2GM}{c^2}$$
The question ...
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Someone explain how a naked singularity is possible
I was reading this wiki article about naked singularities, however I don't really understand the how a gravitational singularity can simply exist without an event horizon. Can someone explain/...
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why would a black hole have a singularity point ? (a ring or disk seams more likely to me)
I'm not a physician nor an astronomer, I am just curious.
When I think that a star collapses, and think of large bodies that rotate.
Then it's likely that the sphere is not a perfect sphere.
Most ...
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Is the hypothetical '(Don) Page curve' of evaporating black holes equal in time, so to speak, on both sides of the curve?
I have heard that Hawking radiation is slow at first, but rapidly increases when the black hole becomes much smaller... (I forget the formula...)
Does that mean that the second half of Page's curve, ...
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What exactly is a 'gravastar'? How is it different from a 'regular' black hole?
The Wikipedia article on gravastar says that it has a 'regular' black hole metric (Schwarzschild, I presume?) on the outside, but a de Sitter metric on the inside....
What exactly does that mean?
Don'...
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Stellar Mass Black Holes and the companion star dynamics
I was studying stellar mass black holes and wondered why almost all of them had a companion star, I came through many explanations but was not satisfied, is it because its hard to detect them without ...
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Does an infalling observer ever cross the black hole event horizon in finite proper time?
I am interested in how an infalling observer perceives the plunge into a black hole.
Let me assume that actually we have three spaceships: C being at a constant distance to the event horizon, and A ...
user56648
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Evolution of black holes. Could they lose mass faster than the Hawking radiation?
As far as I understood the biggest black holes we know are at the centre of very distant quasars and they are enormous. All the big black holes are very far away. At the centre of the closer galaxies ...
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Black Hole Photon Ring
NASA recently published a video simulation of what it would look like flying into a black hole (video can be seen here ).
What confuses me is that it appears to show the photon ring around the black ...
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Does nucleosynthesis such as R Process, S Process, and P process occur in relativistic jets?
By answering a recent question about relativistic jets and their cooling I became more curious about relativistic jets. This might be a totally another sub topic on relativistic jets. But I was ...
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Why are black holes oblate spheroids?
I just heard something I have heard a million times before: "The shape of a spinning black hole is an oblate spheroid." This time, it hit me as odd that a black hole's shape changes with a ...
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Have measurements been conducted on the position of the galactic center of mass and the orbit of the presumed black hole at the center?
Related questions have been raised before
Is our central black hole actually at the CG of the galaxy?
Orbiting supermassive black hole or galactic center of mass?
, where explanations have been given ...
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Does a relativistic jet contain dust particles?
Black-holes accreting matter can emit jets of plasma that can exceed half the speed of light.
Can these jets cool off enough that dust particles condense in them? If so, could we detect flashes of ...
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A couple of questions on Hawking radiation
Black holes progressively evaporate due to the emission of Hawking radiation just outside their event horizon primarily in the form of photons. However, there is a small probability that they emit ...
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