All Questions
13
questions
2
votes
2
answers
136
views
What happens if $ a^2 > M^2 $ in Kerr metric?
(Boyer-Lindquist coordinates and $ c = G =1 $ taken)
As I know, line element in Kerr metric $ d s^2 = - \left( 1 - \frac{2Mr}{\rho^2} \right) d t^2 - \frac{4 M a r \sin^2 \theta}{\rho^2} d \phi d t + \...
- 25
0
votes
0
answers
23
views
Is it possible for a black hole singularity to interact gravitationally with other celestial bodies (if we analyze it using the concept of gravitons)? [duplicate]
It is known to all that the travelling speed of gravitons (the propagation speed of gravitational field) is not instant. So for black holes, the gravitons (the gravitational field) generated by the ...
0
votes
0
answers
106
views
How is the singularity of Schwarzschild space-like if a one can take a time like path to it?
It is known that when one crosses the event horizon of a Schwarzschild black hole, one cannot return and is destined to hit the $r=0$ horizon. My understanding is that this can be seen from the ...
0
votes
0
answers
216
views
What kind of causality would be broken if black hole singularities would be real?
In his article "The Universe as a Whole" 1, physicist Dennis Sciama said
We therefore face a crisis in theoretical physics. Either classical general relativity breaks down, or effectively ...
- 2,462
0
votes
1
answer
168
views
What is a naked singularity?
What is a naked singularity? Would a naked singularity be one that that the event horizon is so small that it is the same size as the singularity? what could make one that small?
- 2,706
2
votes
1
answer
247
views
What do I see looking forward inside the black hole? [closed]
I have read this question:
Future light cones inside black hole
What happens to light that falls into a black hole?
What would be the view like from inside a black hole looking towards the event ...
- 29k
7
votes
2
answers
507
views
How do we know we cannot escape the event horizon?
A doubt assails me: deepening the Schwarzschild and Kerr space-times I found a beautiful article of the University of Rome, which provides a method to identify an event horizon based on the analysis ...
1
vote
0
answers
56
views
Can a solid object inside the black hole event horizon avoid the singularity? [duplicate]
I will ask this as a simple lay man. Let's consider an astronomical black hole that was creating by in falling matter on a neutron star. As neutron star get heavier it gets smaller and a Schwarzschild ...
- 113
7
votes
4
answers
1k
views
"Center of a black hole is a time"
$\newcommand{\d}[1]{\mathrm{d} #1}$In one lecture (around 1:33:15) of the series of lectures "Theoretical Minimum" of Prof. Susskind he talks about black holes and the Schwarzschild metric:
$$\d \tau^...
- 4,021
1
vote
1
answer
354
views
Do all paths leading into a black hole lead directly at the exact center of the singularity? Or could they go very near it and curve back?
I only have a very basic understanding of general relativity, so this might sound stupid. But as I see that gravitational objects orbiting each other, even if one of them is massive, as long as their ...
- 862
0
votes
1
answer
286
views
Misner String Singularity
In correspondence to AdS black hole solutions, what does it mean by Misner string singularities? And when there are no Misner string singularities, what does this mean in terms of curvature ...
- 1,306
3
votes
2
answers
214
views
How to make a black hole?
Many Physics discussions I have often conclude with:
Well you will then form a black hole...
My questions are:
Is there a general recipe for making a black hole?
If not, then can you list the ...
- 227
21
votes
5
answers
3k
views
Event horizons without singularities
Someone answered this question by saying that black hole entropy conditions and no-hair theorems are asymptotic in nature -- the equations give an ideal solution which is approached quickly but never ...
- 5,148