Creating a magnetic field at a distance

Point out news stories, on the net or in mainstream media, related to polywell fusion.

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bennmann
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Creating a magnetic field at a distance

Post by bennmann »

https://www-livescience-com.cdn.ampproj ... -afar.html

Edit:
Abstract: https://journals.aps.org/prl/abstract/ ... 125.177204

(Thanks to comments for this improvement)
/Edit


Any of the retirees here want to reproduce this result? Seems like something like this could help eliminate ion losses for a inertial static fusion system, if some creative geometry is involved.
Last edited by bennmann on Wed Nov 25, 2020 7:18 pm, edited 1 time in total.

Skipjack
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Re: Creating a magnetic field at a distance

Post by Skipjack »

LOL, it is livescience...
The science in the name has nothing to do with the idiotically shitty content on the website. I got banned from their comment sections because I kept pointing out their BS. I am not even going to bother reading the article.

93143
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Re: Creating a magnetic field at a distance

Post by 93143 »

Physical Review Letters: https://journals.aps.org/prl/abstract/1 ... 125.177204

Better?

Yes, it's paywalled, but you can at least read the abstract for free...

bennmann
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Re: Creating a magnetic field at a distance

Post by bennmann »

93143 wrote:
Wed Nov 25, 2020 2:04 pm
Physical Review Letters: https://journals.aps.org/prl/abstract/1 ... 125.177204

Thank you!

Skipjack
Posts: 6167
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Re: Creating a magnetic field at a distance

Post by Skipjack »

Hmm, interesting.
Could have application in some fusion reactor designs. Question is how efficient those magnets can be.

93143
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Joined: Fri Oct 19, 2007 7:51 pm

Re: Creating a magnetic field at a distance

Post by 93143 »

I was thinking warp drive.

I've often thought that if anything like the Woodward theory is possible, a very little confined plasma could in principle be excited to produce significant gravitational effects. And Lentz (2020) explicitly suggested confined plasma as a gravitational source in his energy-condition-respecting superluminal soliton. But obviously you don't want gravity of that magnitude exerted within a structure composed of ordinary matter, so the focus must somehow be projected clear of the spacecraft. I was imagining some sort of tuned field cancellation/reinforcement, which I guess isn't too far off the subject of that paper...

But fusion would be cool too, I guess... gotta have some way to power the warp drive...

Giorgio
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Re: Creating a magnetic field at a distance

Post by Giorgio »

93143 wrote:
Fri Nov 27, 2020 8:14 am
And Lentz (2020) explicitly suggested confined plasma as a gravitational source in his energy-condition-respecting superluminal soliton.
It is an interesting theoretical paper but energy requirements for now are in the same range as Alcubierre drive, so it is out of our technological testing possibilities.
A society of dogmas is a dead society.

Munchausen
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Re: Creating a magnetic field at a distance

Post by Munchausen »

"Controlling magnetism, essential for a wide range of technologies, is impaired by the impossibility of generating a maximum of magnetic field in free space. Here, we propose a strategy based on negative permeability to overcome this stringent limitation. We experimentally demonstrate that an active magnetic metamaterial can emulate the field of a straight current wire at a distance. Our strategy leads to an unprecedented focusing of magnetic fields in empty space and enables the remote cancellation of magnetic sources, opening an avenue for manipulating magnetic fields in inaccessible regions."

Sounds like an ideal tool for improving various electrostatic fusion schemes.

93143
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Joined: Fri Oct 19, 2007 7:51 pm

Re: Creating a magnetic field at a distance

Post by 93143 »

Giorgio wrote:
Fri Nov 27, 2020 12:13 pm
93143 wrote:
Fri Nov 27, 2020 8:14 am
And Lentz (2020) explicitly suggested confined plasma as a gravitational source in his energy-condition-respecting superluminal soliton.
It is an interesting theoretical paper but energy requirements for now are in the same range as Alcubierre drive, so it is out of our technological testing possibilities.
thatsthejoke.jpg

(Well, that and my proposed workaround isn't exactly common practice either...)

Seriously, anything that moves FTL travel closer to reality is a good thing, but I can't speak to potential nearer-term fusion applications because I'd have to be more specific and less handwavy, and I haven't read the paper.

Giorgio
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Re: Creating a magnetic field at a distance

Post by Giorgio »

93143 wrote:
Fri Nov 27, 2020 10:31 pm
and I haven't read the paper.
Here is the paper for anyone interested in reading it:
Tailoring magnetic fields in inaccessible regions.pdf
The link is valid for 14 days.

If is is as described it is a neat finding plenty of potential applications, but the paper I got is lacking of the " supplementary material" that they mention few times into the paper itself, so everything should be taken with care.

Anyhow, worth of attention is the conclusion:
"Another area of application is in atom trapping.Depending on the atom’s state, they can be trapped in magnetic field minima (low-field seekers) or maxima(high-field seekers). Since local maxima are forbidden by Earnshaw’s theorem, high-field seekers are typically trapped in the saddle point of a magnetic potential that oscillates in time [26]. However, these dynamic magnetic traps are shallow compared to traps for low-field seekers [27, 28]. By emulating a magnetic source at distance,one would be able to generate magnetic potential landscapes with higher gradients at the desired target position resulting in tighter traps."
A society of dogmas is a dead society.

Munchausen
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Re: Creating a magnetic field at a distance

Post by Munchausen »

"By emulating a magnetic source at distance,one would be able to generate magnetic potential landscapes with higher gradients at the desired target position resulting in tighter traps."

Please excuse my ignorance, but what confinement method could be better than a magnetic field occuring out of nothing in empty space?

Giorgio
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Re: Creating a magnetic field at a distance

Post by Giorgio »

Munchausen wrote:
Sun Nov 29, 2020 6:46 pm
"By emulating a magnetic source at distance,one would be able to generate magnetic potential landscapes with higher gradients at the desired target position resulting in tighter traps."

Please excuse my ignorance, but what confinement method could be better than a magnetic field occuring out of nothing in empty space?
The magnetic field needs to be generated by several sources on the outside of a volume to trap something inside that volume. The point of contact of the various field sources will create weak confinement areas that create potential roads for losses. You can visualize it as a valley that forms where two different mountain chains get into contact.
The idea proposed is to "emulate" a mountain at the entrance of the valley to prevent (limit) the potential escape route, thus creating a tighter trap.
A society of dogmas is a dead society.

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