Linked Questions

0 votes
0 answers
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Why don't black holes have magnetic hair? [duplicate]

Possible Duplicate: What happens to an embedded magnetic field when a black hole is formed from rotating charged dust? It is well stablished that the only hair a black hole can have is: mass ...
lurscher's user avatar
  • 14.4k
488 votes
21 answers
53k views

How does gravity escape a black hole?

My understanding is that light can not escape from within a black hole (within the event horizon). I've also heard that information cannot propagate faster than the speed of light. I assume that the ...
Nogwater's user avatar
  • 4,999
29 votes
3 answers
4k views

Detection of the Electric Charge of a Black Hole: How can an electromagnetic field escape the event horizon of a Reissner-Nordström black hole?

By the "No Hair Theorem", three quantities "define" a black hole; Mass, Angular Momentum, and Charge. The first is easy enough to determine, look at the radius of the event horizon and you can use the ...
Benjamin Horowitz's user avatar
10 votes
1 answer
1k views

If a magnetic monopole falls into a schwarzchild black hole, what happens to the magnetic field?

By the no-hair theorem, black holes can only have mass, charge and angular momentum. Does "charge" include "magnetic charge" (such as from a magnetic monopole)? Can black holes have magnetic charge ...
FrankH's user avatar
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11 votes
2 answers
2k views

If you are carrying a magnet, can you tell when you cross the event horizon of a black hole?

By the no hair theorem, a black hole is completely characterized by it's mass, charge and angular momentum. Therefore dipole and higher pole magnetic fields are completely expelled when a black hole ...
FrankH's user avatar
  • 10.7k
8 votes
1 answer
1k views

When a neutral star with a magnetic field collapses to form a black hole, what happens to the magnetic field?

By the no-hair theorem, black holes are only characterized by mass, charge and angular momentum. If the star is neutral, the black hole will have only mass and angular momentum - and therefore it ...
FrankH's user avatar
  • 10.7k
1 vote
2 answers
2k views

Should black holes have magnetic fields?

Should a black hole, in the absence of all external electromagnetic forces, generate its own magnetic field? Would all particles in the vicinity of the black hole by effected by this magnetic field--i....
Max's user avatar
  • 383
1 vote
1 answer
339 views

How does a black hole have a magnetic field? [duplicate]

If a black hole is defined as an area where gravity is so great, it has a theoretical escape velocity that is faster than the speed of light. So how, since the carrying particle of magnetic force is a ...
Ralph's user avatar
  • 11
2 votes
0 answers
310 views

Electric and magnetic field in a black hole

I have many questions about this topic: Does the electric field of a charged black hole look like this? I mean how can it have an electric field if nothing can escape from a black hole, and what is ...
Angelica Gutierrez's user avatar
5 votes
1 answer
82 views

Black hole's (gauge) charge and its associated field

If you have a black hole characterized by its mass, angular momentum, and charge (say electric charge) then how can this black hole have an associated field (electromagnetic)? I.e. if the field is ...
user122066's user avatar
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2 votes
0 answers
60 views

How do black holes get their magnetic fields?

I imagine the magnetic field comes from the accretion disk. But what causes it to "spring" upward?
Orangeman's user avatar