Create Black Holes with Warping EM Fields: Feasible?

In summary, the physicist is trying to find a way to travel faster than light and has come up with several ideas that are not feasible. He is also aware of the way that would require an energy source equivalent to several of our solar system's suns and is not sure how electromagnetic fields could be manipulated in a way to warp space-time to the extent of creating a black hole. He is not sure if the Schwarzschild solution should represent the exterior of a collapsed sphere with an EM field inside, or if an Oppenheimer-Snyder model could be created.
  • #1
Ascendant78
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TL;DR 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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  • #2
Ascendant78 said:
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.

Ascendant78 said:
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.

Ascendant78 said:
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.
 
  • #3
PeterDonis said:
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
 
  • #4
Dale said:
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.

Dale said:
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.
 
  • #5
PeterDonis said:
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.
PeterDonis said:
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.
 
  • #6
Dale said:
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.

Dale said:
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.
 
  • #7
PeterDonis said:
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.
 
  • #8
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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  • #9
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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  • #10
Ibix said:
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.
 
  • #11
PeterDonis said:
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".
 
  • #12
Dale said:
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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  • #13
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.
 
  • #14
Ascendant78 said:
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.
 
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  • #15
Ascendant78 said:
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).
 
  • #16
Dale said:
Well, there isn’t exactly a big market for black holes.

A black hole is the intermediary to a wormhole, so I'm honestly at a loss as to how it *ISN'T* a HUGE market for people interested in inter-stellar travel?

What I fail to understand is that for inter-stellar travel to occur, we understand (generally speaking in the respective realm of physics) that space-time warping must occur. As such, the next step for us to travel to other solar systems is the warping of space-time, yet it doesn't seem to be a priority to ANYONE in the realms of the various sub-fields of physics from what I have seen to date? Am I alone here in thinking we are failing to grasp the much bigger picture that we should be reaching for?
 
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  • #17
Ascendant78 said:
A black hole is the intermediary to a wormhole,
Do you have a reference for that? And I mean a reference with maths, not a piece of pop-sci fluff. If you don't have such a reference then you have your answer - you aren't talking about anything real.
Ascendant78 said:
yet it doesn't seem to be a priority to ANYONE in the realms of the various sub-fields of physics from what I have seen to date?
All methods that purport to permit faster than light travel by warping spacetime require large quantities of "exotic matter", with negative energy density. We don't even know where to begin on creating such a thing - indeed it may be impossible. How much resource should we sink into hunting a unicorn?
Ascendant78 said:
Am I alone here in thinking we are failing to grasp the much bigger picture that we should be reaching for?
The problem is that a universe where we can readily warp spacetime to allow faster than light travel is a bigger picture you have painted for yourself. Reality has no obligation to reflect it. At the moment we cannot create exotic matter and it may well be impossible, and permitting faster than light travel can lead to causal paradoxes in our current theories. So our current understanding of the universe precludes faster than light travel, however much we might wish it otherwise.
 
  • #18
Ascendant78 said:
A black hole is the intermediary to a wormhole, so I'm honestly at a loss as to how it *ISN'T* a HUGE market for people interested in inter-stellar travel?
First, that isn’t true. As @PeterDonis mentioned in post 2 black holes are not the same as wormholes. I don’t know what you mean by “intermediary” but you don’t get interstellar travel from a black hole.

Second, as far as I know the current market for interstellar travel is 1 person: Elon Musk. That is not a huge market.

Ascendant78 said:
What I fail to understand is that for inter-stellar travel to occur, we understand (generally speaking in the respective realm of physics) that space-time warping must occur.
I completely disagree. Interstellar travel would be possible without spacetime warping simply by accelerating at 1 g for extended periods e.g. with rockets. That is indeed the only mechanism that is consistent with the currently known laws of physics and matter. Anything else is science fiction.
 
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1. Can we actually create black holes with warping EM fields?

Currently, there is no known way to create a black hole using warping EM fields. The conditions required to create a black hole are extreme and cannot be replicated with current technology.

2. What are warping EM fields?

Warping EM fields are electromagnetic fields that have been manipulated to bend or distort the fabric of spacetime. This concept is based on Einstein's theory of general relativity.

3. How do warping EM fields affect space and time?

Warping EM fields can cause space and time to warp or distort, similar to how a heavy object can create a dip in a trampoline. This distortion is what creates the gravitational pull associated with black holes.

4. Are there any potential risks in attempting to create black holes with warping EM fields?

Since we do not currently have the technology to create black holes, the potential risks are purely theoretical. However, if we were able to create a black hole, it could potentially have unpredictable and catastrophic effects on its surroundings.

5. What are the potential applications of creating black holes with warping EM fields?

The creation of black holes using warping EM fields is currently a topic of theoretical research and there are no known practical applications at this time. However, it could potentially lead to a better understanding of gravity and the fabric of spacetime.

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