All Questions
11
questions
2
votes
0
answers
100
views
Can squeezed vacuum reduce the mass of a black hole?
Could the negative energy density parts of squeezed light really reduce the mass of a black hole, as stated here (“A pulse of negative energy injected into a charged black hole might momentarily ...
- 135
17
votes
6
answers
7k
views
How can a grain of sand be "spaghettified" when nearing a black hole?
I have a hard time wrapping my head around this "spaghettification" process that apparently takes places when getting close to a black hole.
Gravity is proportional to the distance of the ...
- 439
1
vote
0
answers
58
views
Black $p$-brane solution
Im trying to confirm that the metric (11) in the paper below is a solution to Einstein's equations (6). I tried to use the metric and extract $\lambda=(1-(r_+/r)^{D-3})^{1/2-\gamma/2(D-3)}$ and $R=r(1-...
- 63
1
vote
1
answer
84
views
What happens when a galactic body gets bigger?
In my simple non-quantum non-nuclear but enthusiasm-filled mind, I fascinate that as a galactic body become much more massive, it can reduce matter first down to its building blocks, then eventually ...
- 137
2
votes
0
answers
131
views
Elementary particle (electron) and non-elementary (proton) spagettification
I understand that spagettification means the vertical stretching and horizontal compression of objects into long thin shapes in a non-homogenous gravitational field, it is caused by tidal forces.
Now ...
- 29k
5
votes
1
answer
622
views
Charge without charge and non-traversable wormholes
My question concerns the theory proposed in this classic paper by Misner and Wheeler. In the paper, the authors propose the idea of "charge without charge"--namely, that positive and negative ...
- 2,665
1
vote
1
answer
435
views
If a black hole is just warped spacetime, then where is the electric charge?
I've heard Kip Thorne repeatedly state that matter is destroyed when a black hole is created, that all you are left with is distorted spacetime.
"The idea that black holes are made from very ...
- 51
0
votes
1
answer
262
views
What is the smallest amount of neutrinos needed to create a black hole? [duplicate]
Is there some smallest amount of neutrinos needed to create a black hole?
Note that this question is not at all the same as the question here If a 1kg mass was accelerated close to the speed of light ...
- 1,005
3
votes
1
answer
662
views
Metric Perturbations in General Relativity and quasi-normal modes?
I am familiar with the tools that appear in (linear) perturbation theory for general relativity, that is namely that one writes:
$$g_{\mu \nu} = g^{(0)}_{\mu \nu} + \epsilon g^{(1)}_{\mu \nu} + \...
- 1,525
11
votes
4
answers
3k
views
What is the difference between a black hole and a point particle?
Theoretically, what is the difference between a black hole and a point particle of certain nonzero mass? Of course, the former exists while it's not clear whether the latter exists or not, but both ...
- 2,152
19
votes
5
answers
2k
views
Are elementary particles ultimate fate of black holes?
From the "no hair theorem" we know that black holes have only 3 characteristic external observables, mass, electric charge and angular momentum (except the possible exceptions in the higher ...
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