Questions regarding points of extremely high mass density, which creates an extremely strong gravitational field from which light cannot escape.

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4
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4answers
562 views

Escaping a black hole

I often hear that nothing can escape a black hole because it's "escape velocity" is greater than c. If that is accurate, what about the following. I know that the following has a lot of most likely ...
26
votes
6answers
875 views

How are black holes found?

Black holes have so much gravity that even light can't escape from them. If we can't see them, and the suck up all electromagnetic radiation, then how can we find them?
8
votes
2answers
365 views

Does matter accumulate just outside the event horizon of a black hole?

My understanding is that time slows and approaches stopping when approaching the event horizon of a black hole. I have seen this explained several places, including a brief explanation in the last ...
4
votes
2answers
294 views

Is it possible that a ultra-large portion of the space we live in is already inside a black hole? How could we refute this?

Trying to wrap my head around some concepts involving the very large gravitational fields of black holes, and what the gravitational gradients look like on a cosmic scale. I'm familiar with the Great ...
-3
votes
1answer
136 views

Black Holes, how do they form?

Do black holes form by when the massive star dies and all the gravity falls in on itself, or something else. Please let me know, I'm really desperate!!
18
votes
3answers
664 views

Why can't light escape from a black hole?

I've heard that light can't escape from a black hole. Can it? If not, why?
6
votes
2answers
397 views

How deep and shaped is the depth of a black hole?

A common representation of a black hole is a black circle which if I'm correct, indicates its breadth. This representation depicts it as a 'plate', so a really small depth compared to its breadth. ...
9
votes
5answers
208 views

Orbiting around a black hole

Is it possible (for either a satellite or a planet) to orbit around a black hole? Do they attract everything around themselves into the center? Or they just affect gravitational force just like stars? ...
19
votes
5answers
826 views

Can we (theoretically) spin the black hole so strong that it will be broken apart by centrifugal force?

I can't imagine the forces involved in black holes' lives. So please, help me to find out, if it is possible or not to destroy black hole in this specific way.
6
votes
3answers
315 views

What is a singularity? What is at the center of a black hole? Specifically regarding space-time

So because I can only really think of space-time in 2-dimensions like a sheet of something, my assumptions might be wrong to begin with. I was watching a YouTube video on black-holes and there was a ...
4
votes
2answers
228 views

Do black holes have energy?

So black holes are created by certain dying stars and when the star runs out of nuclear energy gravity wins out and the star implodes. An entire star’s mass collapses down into a smaller and smaller ...
4
votes
2answers
111 views

Assuming a sufficient amount of mass above the density threshold, does the actual concentration of the mass matter in creating a black hole?

I've heard that the actual density of a black hole (within the volume of the event horizon) is pretty low - does that mean that any sufficiently large volume of mass over that density is also a black ...
4
votes
2answers
203 views

Why does time get slow near a black hole? [closed]

Why exactly does time get slow around a black hole? And does it provide a way to go into the future?
3
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2answers
1k views

Does a black hole become a normal star again?

Stars which satisfy the Chandrasekhar limit can become a black hole. What happens to star after it becomes a black hole? Does it regain its status of star?
3
votes
1answer
100 views

What does black hole evaporation correspond to in the accelerating universe / black hole analogy?

In the same way, as a black hole emits Hawking radiation corresponding to its temperature $$ T = \frac{\hbar}{r_{BH}} $$ the accelerating universe can be described as all of the stuff falling ...
2
votes
2answers
65 views

how to know the nature of the companion in a neutron star binary?

The companion could be a main sequence star, white dwarf, neutron star or black hole. We detected pulsar-pulsar binaryhere several decades ago. But if one of the pulsar does not radiate towards us, ...
2
votes
2answers
154 views

Is it dark inside a black hole?

Assuming you could be standing inside a black hole, would it be light or dark around you?
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vote
1answer
49 views

Under Earth's gravitational pull, how dense would an object have to be to reach its Schwarzschild Radius?

The Schwarzschild Radius is a theoretical radius, that if the mass of the object was compressed into that certain radius, the escape speed from the surface of the compressed object would equal the ...
0
votes
1answer
64 views

Is a black hole a 5 dimensional vortex?

We know that a black hole behaves like a whirlpool or a tornado or any of the other rotating phenomena we experience on Earth.But the thing is, all these phenomena, except the black hole, are ...