The discussion explores the hypothetical scenario of increasing the electrical charge of an extremal black hole, particularly focusing on the implications of adding a significant number of electrons. Participants examine the interplay between electromagnetic forces and gravitational forces in this context.
Participants do not reach a consensus on the effects of increasing an extremal black hole's charge, with multiple competing views and uncertainties remaining about the interplay of forces involved.
The discussion includes assumptions about the nature of black holes and the effects of adding charge, which are not universally agreed upon. There are unresolved questions regarding the implications of general relativity in this context.
Drakkith said:I've never heard of the electromagnetic force overcoming the gravitational pull of a black hole. Are you sure about that?
If you just added more electrons to it, it would just stay an extremal black-hole with a larger charge and mass... if you magically added only charge, and not mass---well, GR says you can't do that.kcajrenreb said:If you were to greatly increase the elctrical charge of an extremal Black Hole, (ie, drop a lot of electron in) what exactly would happen to it? I know the electrical repulsion would become more powerful than the gravity, so would it tear itself apart?
Its not quite as simple as EM 'overcoming' gravity, nothing can 'overcome' the gravity. But you can get very exotic spacetime geometries... perhaps even naked singularities according to some loop quantum gravity, and pure GR extrapolations...Drakkith said:I've never heard of the electromagnetic force overcoming the gravitational pull of a black hole. Are you sure about that?
zhermes said:If you just added more electrons to it, it would just stay an extremal black-hole with a larger charge and mass... if you magically added only charge, and not mass---well, GR says you can't do that.
twofish-quant said:Specifically imagine that you add a lot of electrons to the black hole. The electrons all have negative charges so they are repelling each other. However, those negative charges have stored potential energy and that energy has an equivalent mass (E=mc^2).
So if you try to add enough charge to blow the black hole apart, what happens is that that charge has potential energy which has mass which has gravity which keeps the black hole together.