All Questions
Tagged with black-holes singularities
118
questions
41
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10
answers
12k
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Does any particle ever reach any singularity inside the black hole?
I am not a professional physicist, so I may say something rubbish in here, but this question has always popped in my mind every time I read or hear anyone speak of particles hitting singularities and "...
user1549
14
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2
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Is a black hole singularity a single point?
General relativity is expressed in terms of differential geometry, which allows you to do interesting things with the coordinates: multiple coordinates may refer to a single point, eg. the ...
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38
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9
answers
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Why singularity in a black hole, and not just "very dense"?
Why does there have to be a singularity in a black hole, and not just a very dense lump of matter of finite size? If there's any such thing as granularity of space, couldn't the "singularity" be just ...
- 530
26
votes
7
answers
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Why did the universe not collapse to a black hole shortly after the big bang?
Wasn't the density of the universe at the moment after the Big Bang so great as to create a black hole? If the answer is that the universe/space-time can expand anyway what does it imply about what ...
- 517
24
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6
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What is exactly the density of a black hole and how can it be calculated?
How do scientists calculate that density? What data do they have to calculate that?
- 1,533
19
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3
answers
4k
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Are black holes really singularities?
A popular assumption about black holes is that their gravity grows beyond any limit so it beats all repulsive forces and the matter collapses into a singularity.
Is there any evidence for this ...
- 325
66
votes
10
answers
10k
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Do all black holes have a singularity?
If a large star goes supernova, but not enough mass collapses to form a black hole, it often forms a neutron star. My understanding is that this is the densest object that can exist because of the ...
- 5,061
20
votes
4
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How can a singularity in a black hole rotate if it's just a point?
I guess nobody really knows the true nature of black holes, however, based on everything I know about black holes, there is a "singularity" at their center, which has finite mass but is infinitely ...
- 912
24
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7
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Given that matter cannot escape a black hole, how did the big bang produce the universe we see today?
Extrapolation of the expansion of the Universe backwards in time using general relativity yields an infinite density and temperature at a finite time in the past.
If the matter contained within our ...
Daniel X Moore
19
votes
3
answers
6k
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Can we have a black hole without a singularity?
Assuming we have a sufficiently small and massive object such that it's escape velocity is greater than the speed of light, isn't this a black hole? It has an event horizon that light cannot escape, ...
- 677
20
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5
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Why does a black hole have a finite mass?
I mean besides the obvious "it has to have finite mass or it would suck up the universe." A singularity is a dimensionless point in space with infinite density, if I'm not mistaken. If something is ...
- 5,061
12
votes
2
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3k
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When does a singularity start to exist during a black hole formation?
Excuse me if the question is naïve. I am not a physicist.
Let's imagine formation of a black hole from a homogeneous collapsing star. At certain moment when enough of matter is inside of a small ...
14
votes
3
answers
2k
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Fighting a black hole: Could a strong spherical shell inside an event horizon resist falling in to the singularity?
As a thought experiment imagine an incredibly strong spherical shell with a diameter a bit smaller than the event horizon of a particular large black hole. The shell is split into two hemispheres, ...
- 671
27
votes
6
answers
6k
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Why exactly are singularities avoided or "deleted" in physics?
What is the real reason that make us reject singularities everytime we see them in a theory/model?
For example, in GR, it is predicted that black holes singularities have infinite density. This makes ...
- 405
18
votes
2
answers
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What does string theory predict for the singularity inside a black hole?
The usual explanation for what's going on inside a black hole goes something like "General Relativity predicts a singularity with infinite curvature, but when matters gets so tightly compressed we ...
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