I Black hole generated by warping electromagnetic fields -- possible?

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Summary
Lacking the foundation needed to know for sure, I was curious as to whether or not the notion of creating a black hole with electromagnets is possible, or only sci-fi hokum?
As a prior physics major (had to stop at my 3rd year of undergrad due to children and financial difficulties), there was something I was always extremely passionate about - finding feasible ways to travel faster than light. Obviously, the only feasible way seems to be to bend space-time, but I wasn't quite sure of the best section to place this in, since general relativity would be involved as well.

Now, I already know about the ones involving exotic matter. Since we haven't even confirmed its existence (to the best of my knowledge), that isn't feasible to me.

I am also aware of the way that would require an energy source equivalent to several of our solar system's suns. Again, that of course doesn't seem feasible to me.

While I have seen the electromagnetic field making an artificial black hole proposal in sci-fi movies multiple times, it has never made sense to me. I'm not sure exactly how electromagnetic fields could be manipulated in a way to warp space-time to the extent of creating a black hole. With that said, is it theoretically possible, and if so, how? I see so many issues with this, and no feasible way to actually make it happen. Can anyone give some insight?
 
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I was always extremely passionate about - finding feasible ways to travel faster than light. Obviously, the only feasible way seems to be to bend space-time
That won't work either. Curved spacetime does not change the rule that nothing can go faster than light. It just means you need to be more careful about what the rule actually means.

I already know about the ones involving exotic matter.
I assume you mean wormholes. They don't let you travel faster than light. They just create a spacetime geometry where you can go somewhere one way faster than a light ray traveling a different way can get there (because the other way is much longer--the wormhole is something like creating a bridge over a river instead of having to go way, way upstream to find a crossing point and then way, way back downstream to your destination). But light can go through the wormhole just like you can, and if it goes through the wormhole it will get to your destination before you do. So you're not traveling faster than light.

I'm not sure exactly how electromagnetic fields could be manipulated in a way to warp space-time to the extent of creating a black hole. With that said, is it theoretically possible, and if so, how?
First, a black hole is not the same as a wormhole. You can't use a black hole to travel anywhere; one you're inside, you can't escape.

Second, in principle EM fields, since they have stress-energy, could possibly be compressed inside a sphere with small enough area that they would collapse to a black hole. However, I'm not aware of any actual solution to the Einstein Field Equation of this sort that has been found.
 
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Second, in principle EM fields, since they have stress-energy, could possibly be compressed inside a sphere with small enough area that they would collapse to a black hole. However, I'm not aware of any actual solution to the Einstein Field Equation of this sort that has been found.
If it was spherically symmetric then the Schwarzschild solution should represent the exterior. I am not sure if the Oppenheimer Snyder could easily be modified to start with a null dust
 
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If it was spherically symmetric then the Schwarzschild solution should represent the exterior.
The only spherically symmetric solution I'm aware of with EM fields present is the Reissner-Nordstrom solution, which describes a charged, non-rotating black hole. However, I'm not aware of any corresponding Oppenheimer-Snyder model for how such a hole could be formed by collapse. The obvious issue is that like charges repel.

If you had something like a metal sphere with EM fields inside, but idealize the sphere as providing perfect shielding so there is no EM field outside, then the Schwarzschild solution would describe the exterior, yes. Then if you made the sphere collapse, you might possibly have a model that could compress an EM field into a black hole; but the sphere would be an extra piece of stress-energy in addition to the EM field. I don't know if anyone has tried this type of model.

I am not sure if the Oppenheimer Snyder could easily be modified to start with a null dust
I think it could, but null dust is not the same as an EM field as far as GR is concerned; it's an idealization that has a different stress-energy tensor from that of an EM field.
 
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The obvious issue is that like charges repel.
I wasn't thinking of any charged matter, just pure EM waves. Either something like an inward focused coherent pulse of light or a bath of incoherent light.
null dust is not the same as an EM field as far as GR is concerned
Hmm, I thought that null dust modeled a field of isotropic and homogenous incoherent EM radiation. I admit to never having looked at the details.
 
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I wasn't thinking of any charged matter, just pure EM waves. Either something like an inward focused coherent pulse of light or a bath of incoherent light.
This won't be spherically symmetric, since EM radiation is dipole. The only reason the Reissner-Nordstrom solution can be spherically symmetric is that there is no B field, only a static Coulomb E field.

I thought that null dust modeled a field of isotropic and homogenous incoherent EM radiation.
"Models" in the sense that it is a good enough approximation for many purposes, yes. But it is not an exact model. Null dust is a perfect fluid with ##p = \rho / 3##. The stress-energy tensor of an electromagnetic field can never take perfect fluid form.
 
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This won't be spherically symmetric, since EM radiation is dipole. The only reason the Reissner-Nordstrom solution can be spherically symmetric is that there is no B field, only a static Coulomb E field.
Right, of course.

I wonder what the field would look like formed from a very large sphere of lasers all pointed inward and focused to the maximum extent possible. Especially what happens as you introduce gaps between the laser apertures.
 

Ibix

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Side note: infalling null dust is described by the ingoing Vaidya metric. I don't know if it can describe the formation of a black hole - perhaps you can set an initial mass density low enough not to be a hole and let the dust coalesce?

This obviously doesn't answer Peter's objection to null dust as a model for radiation.
 
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martinbn

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Another side note: One doesn't need to have an explicit solution, or as the relativists call them exact solution. It would be enough to know that such solutions exist. Proving it may be very hard, but that is a separate issue. It is known that gravitational radiation can form black holes, at least trapped surfaces, so it seems at least plausible that electromagnetic radiation can too.
 
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infalling null dust is described by the ingoing Vaidya metric. I don't know if it can describe the formation of a black hole
Yes, it can, just choose an appropriate mass function. But as I have said, null dust is not the same thing as an EM field; it's an approximation that is ok for certain purposes, but it's not the same thing.
 
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it's an approximation that is ok for certain purposes, but it's not the same thing
My background is engineering, so I am usually ok with such approximations as long as it is done within the "certain purposes".
 
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I am usually ok with such approximations as long as it is done within the "certain purposes".
For this discussion, at any rate, that's up to the OP and what he considers "manipulating electromagnetic fields" to mean. Something like your scenario of a very large sphere of lasers all pointed inward and focused would be approximated reasonably well by ingoing null dust (if the laser frequency was high enough).
 
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Thanks for all the feedback. And thanks PeterDonis for clarifying some of the questions I was asking. As far as traveling faster than light, what I was meaning was travel through a wormhole - so getting from one point in space to another through the bending/folding of the space between both areas. You pretty much hit the nail on the head with your clarification there.

And thanks for everyone else's feedback on the topic too. I need to start brushing up on my math and physics again, then take a look into some of these topics mentioned above.

Now, I'm curious about the power requirements to accomplish it. I would imagine if they weren't huge or if there weren't tons of obstacles, surely people would have done it by now.
 
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I would imagine if they weren't huge or if there weren't tons of obstacles, surely people would have done it by now.
Well, there isn’t exactly a big market for black holes.
 

PAllen

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Thanks for all the feedback. And thanks PeterDonis for clarifying some of the questions I was asking. As far as traveling faster than light, what I was meaning was travel through a wormhole - so getting from one point in space to another through the bending/folding of the space between both areas. You pretty much hit the nail on the head with your clarification there.

And thanks for everyone else's feedback on the topic too. I need to start brushing up on my math and physics again, then take a look into some of these topics mentioned above.

Now, I'm curious about the power requirements to accomplish it. I would imagine if they weren't huge or if there weren't tons of obstacles, surely people would have done it by now.
While power requirements are huge, the bigger issue is that large amounts of negative energy are required. At present, there is no evidence for or any reason to believe that large amounts of negative energy can ever be produced. (That is, negative energy in large amounts is required for a traversable wormhole).
 

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