electric charge of a black hole

[bwanaaa]

Since protons are heavier than electrons, they should be closer to the center of a black hole. This gravitational separation of electrons and protons should render the surface of a black hole negatively charged. So when a black hole eclipses a stream of mixed particles - the electrons should be repelled and the protons attracted. Is there any way to experimentally test this hypothesis?

 

[firewolfsm]

As for your question, no, there is no way to experimentally test any theory on black holes, barring a few exceptions.

"A charged black hole is a black hole that possesses electric charge. Since the electromagnetic repulsion in compressing an electrically charged mass is dramatically greater than the gravitational attraction (by about 40 orders of magnitude), it is not expected that black holes with a significant electric charge will be formed in nature." - Wiki

This also means that the charges in a neutral black hole should not align as you stated, with lighter electrons on the outside, because the electrical repulsion between those electrons would overcome mechanics and gravity.

That's assuming your image of a black hole was even correct, black holes are essentially particles, point masses which have the characteristics of spin, mass and charge, only. They do not have shape and charge distribution.

 

[omghaxcode]

That is like saying that this tiny point in space is both negative and positive. there isn't enough room for both.

 

[KIAman]

Since protons are heavier than electrons, they should be closer to the center of a black hole. This gravitational separation of electrons and protons should render the surface of a black hole negatively charged. So when a black hole eclipses a stream of mixed particles - the electrons should be repelled and the protons attracted. Is there any way to experimentally test this hypothesis?

Since when did heavier objects fall any faster than lighter objects? Unless you are implying the minuscule amount of gravity that the heavier proton has an effect on pulling the black hole closer compared to an electron?

 

[Biftheunderstudy]

Actually this sort of makes sense. Higher density material usually settles to the centre of things. Called gravitational settling if I recall.

Same reason why the Earth has a core of iron and heavier elements and why the lighter less dense material floats to the top. Only sort of, not quite the same thing....

 

[KIAman]

That would be true if you were talking about a non-singularity.

 

[bwanaaa]

as a charged particle source is eclipsed by a black hole, the beam should deviate. arent there any charged particle sources in the universe that have been mapped?

 

[Biftheunderstudy]

That would be true if you were talking about a non-singularity.

You're absolutely right, but what if the gravitational settling happens in the accretion disc and the black hole ends up preferentially feeding on one type of charge rather than the other? My hunch is that if the black hole does develop a charge it will then start attracting the opposite charge very strongly in an attempt to come back to neutrality.
Basically, charged black holes seem unlikely since the bulk of the universe is neutral.

 

[silverpig]

First off, protons and electrons will not exist. A neutron star arises when the electron degeneracy pressure which keeps atoms their size is not enough to withstand gravity and the electrons combine with the protons to form neutrons. A black hole is even more dense.

Second, IIRC there is no necessity for a black hole to be a point. Black holes (the mass) can have size, you just have to allow them to be big enough in extent.

Third, as has been mentioned, electrical repulsion is so much greater than gravitational repulsion that it would be very difficult for a black hole to maintain a significant charge. Small charges, sure, but nothing significant.

Fourth, there are solutions to Einstein's field equations which consider a charged black hole. I'm sure you can google them.

 

[JSSheridan]

First off, protons and electrons will not exist. A neutron star arises when the electron degeneracy pressure which keeps atoms their size is not enough to withstand gravity and the electrons combine with the protons to form neutrons. A black hole is even more dense.

In the absence of protons and electrons, what gives the black hole a charge?

 

[silverpig]

In the absence of protons and electrons, what gives the black hole a charge?

You can add electrons to negatively charge it, OR you can add protons which will break up into quarks and gluons and form some kind of weird charged quark-gluon ball or something, but electrons and protons won't exist beside each other, nor will protons exist at as such.

Really though this is a bit moot. In all the calculations I've seen they just "assume a black hole with charge q" and take it from there.

 

[2March]

In the absence of protons and electrons, what gives the black hole a charge?

From what I understand it could be a residu of the charge of star that formed the black hole or, in case of a hole consisting of several stars, the sum of all. It's a bit funky to discuss elementairy particles in an infinitely small volume...

 

[JSSheridan]

From what I understand it could be a residu of the charge of star that formed the black hole or, in case of a hole consisting of several stars, the sum of all. It's a bit funky to discuss elementairy particles in an infinitely small volume...

I'm just not clear what nature of matter would exist in a singularity, if any.

 

[2March]

I'm just not clear what nature of matter would exist in a singularity, if any.

Agreed, hence my post.

We don't even know for sure whether a charged hole exists in the first place. I feel like talking about something that defies all of my logic. Good to know though that I'm not the only one.

 

[Swivelguy2]

First off, protons and electrons will not exist. A neutron star arises when the electron degeneracy pressure which keeps atoms their size is not enough to withstand gravity and the electrons combine with the protons to form neutrons. A black hole is even more dense.

Second, IIRC there is no necessity for a black hole to be a point. Black holes (the mass) can have size, you just have to allow them to be big enough in extent.

Third, as has been mentioned, electrical repulsion is so much greater than gravitational repulsion that it would be very difficult for a black hole to maintain a significant charge. Small charges, sure, but nothing significant.

Fourth, there are solutions to Einstein's field equations which consider a charged black hole. I'm sure you can google them.

And Fifth, If you take a bunch of positive and negative charges and arrange them such that the positive ones are all in the middle and the negative ones are uniformly distributed at some larger distance around the positive ones, there will be no electric field produced outside of the layer of electrons. Think about: what's being talked about here sounds exactly like a NEUTRAL ATOM.