Infinitely strong magnetic field

[Hami Hashmi]

What if you had a charge with a negligible radius and infinitely strong magnetic field or electric charge? Would it form a black hole of infinite mass?

 

[Vanadium 50]

You can't have an infinitely strong field.

 

[Hami Hashmi]

Ok so let's change that to an incredibly strong field then, maybe the Planck magnetic field strength then (10^53 T). Would it then collapse into a black hole?

 

[Vanadium 50]

How do you plan on producing a field of that strength without blowing your magnet into itty bitty pieces?

 

[Hami Hashmi]

I am not actually proposing doing this, i am just asking what would happen if this magnetic field appeared in space and if the magnetic field itself would collapse into a black hole, because of the extremely dense concentration of energy.

 

[Vanadium 50]

The thing is, magnetic fields do not exist in isolation - they are produced by something (things we call magnets). You can't treat the field apart from the thing that produces it.

 

[PeterDonis]

i am just asking what would happen if this magnetic field appeared in space

It can't. You can't just have energy appear out of nowhere in GR. The energy that gets put into the magnetic field has to come from somewhere, and if the magnetic field were strong enough in a small enough space to form a black hole, whatever was going to produce the energy in the field would already have formed one.

 

[vanhees71]

Well, as so often quantum effects come to the rescue. When you get ultrastrong fields, and many physicists try hard to produce some, spontaneous pair creation will take place. It's called the Schwinger mechanism since Schwinger was the first to evaluate the (nonperturbative!) probability for the spontaneous creation of electron-positron pairs in a strong homogeneous electric field. For a nice review, see

https://arxiv.org/abs/1510.05451