All Questions
21
questions
3
votes
0
answers
59
views
Can gravitational waves have event horizons?
Is there a spacetime that contains traveling planar event horizons?
- 519
1
vote
1
answer
495
views
Can gravitational waves escape a black hole? [duplicate]
I know that one of the defining features of a black hole is that all matter, including light, cannot escape a black hole. I was wondering if gravitational waves can. If this is true perhaps we could ...
- 290
1
vote
0
answers
77
views
How close can two black holes in a binary system get, before they merge?
Sorry if this question is too elementary, as is my level, but I'm wondering how close two supermassive black holes can get and should the Keplerian rotational frequency at that point equal to the ...
- 11
0
votes
0
answers
57
views
Do gravitational waves violate the information paradox? [duplicate]
I know when black holes collide, the remnant black hole has a lower mass than the sum of the original two masses. This is due to energy loss via gravitational wave emission.
Does this violate the ...
user203234
2
votes
1
answer
89
views
Why do external observers see LIGO results if an object falling into a black hole never reaches the event horizon? [duplicate]
If I throw a clock towards a black hole, its time slows down, it is redshifted, and according to many theories it never reaches the event horizon from my point of view. How is it then, that a star can ...
- 123
2
votes
1
answer
172
views
What ways are there for a black hole to lose its mass?
How can a black hole lose its mass? Is Hawking radiation the only way?
user175077
11
votes
2
answers
446
views
Colliding black holes
If objects approaching the event horizon of a black hole appear to slow down to outside observers, how was LIGO able to "see" black holes collide? Wouldn't their collision appear to stop as their ...
- 121
1
vote
0
answers
119
views
Should we stop saying that nothing can escape the event horizon of a black hole post LIGO? [duplicate]
Now that LIGO has demonstrated that two black holes can burp large amounts of energy (in the form of gravitational radiation) in the process of consuming each other, shouldn't we stop saying that ...
- 6,022
41
votes
3
answers
4k
views
How much mass can colliding black holes lose as gravitational waves?
Concerning the recent detection of gravitational waves produced by colliding black holes, it has been reported that a significant percentage of the combined mass was lost in the resulting production ...
3
votes
0
answers
85
views
Can gravitational waves observed far from a black hole tell us anything about the multipole moments of a dynamical horizon?
In a paper by Ashtekar et al in 2013 on the approach to the final state to a stationary black hole they study the evolution of the multipole moments of dynamical horizons, which relax away (except for ...
- 14.1k
0
votes
1
answer
49
views
Since the horizon of a Nonstationary isolated black hole is a closed surface, how can gravitational waves be generated?
I understand this is from numerical calculations in GR. I have not seen them. Can anyone elucidate on what generates the GW waves - I know that deformities (anything moments higher than dipole) will ...
- 14.1k
12
votes
3
answers
671
views
Can we detect gravitational waves generated from inside the event horizon of a black hole? [duplicate]
General relativity prevents light from escaping a black hole, but does it also apply to gravitational waves?
- 221
4
votes
2
answers
590
views
How does some of the black hole (BH) mass escape the event horizon (EH) of either BH, or the merged EH of two merged BHs?
BH mass is a conserved quantity and cannot escape the horizon of a BH. Yet in mergers some percent (in GW150914 it was about 5 percent, or 3 solar masses) of the binary's mass escaped either before (...
- 14.1k
14
votes
2
answers
989
views
Did merging Black Holes in GW150914 give up entropy and information to the gravitational waves, since they lost 3 solar masses?
Since the final Black Hole (BH) had 3 solar masses less of mass than the original binary BH, it seems the 2 BHs lost mass, and with it event surface area, entropy, and information. If that came from ...
- 14.1k
8
votes
4
answers
984
views
Binary black hole merger viewed from inside the event horizon
How did the metric evolve inside the event horizons of the black holes whose merger caused the GW150914 signal?
In principle the Schwarzschild metric of a non-rotating black hole is known inside the ...
- 15.7k