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AlarmingAffect0 OP t1_iufnnci wrote

Reply to comment by ehj in Is there such a thing as a gamma radiation mirror? by AlarmingAffect0

> a plasma with a higher density than solid materials

> Perhaps in some astrophysical extreme circumstances you can find something like this.

Does the iron vapor 'atmosphere' at the surface of neutron stars count?

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somneuronaut t1_iufq2ji wrote

IIRC some of the most extreme magnetars produce fields that are higher density than solid materials.

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AlarmingAffect0 OP t1_iufro4v wrote

> fields that are higher density than solid materials.

I literally do not comprehend the concept. Is there some sort of relativistic mass-energy equivalence stuff going on whereby energy density might as well be mass density or…?

I'm completely out of my depth, here.

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somneuronaut t1_iuftvlq wrote

>Is there some sort of relativistic mass-energy equivalence stuff going on

indeed. the surface magnetic fields of magnetars are measured in tens of giga-Teslas. this results in an enormous energy density, which greatly exceeds regular matter, even with its large rest mass term.

edit: some quick napkin math reveals an energy density on the order of hundreds of yotta-joules per meter cubed. aka millions of billions of gigajoules per cubic meter.

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Aquatic-Vocation t1_iugl2w0 wrote

So this is a real-life force-field? If you could isolate it and tried to walk into it, you'd hit a wall?

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Byrmaxson t1_iugnjvz wrote

Less wall and more if you approach within a certain distance you'll be atomized entirely, but yes, it's basically a sci-fi force field.

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ajt9000 t1_iuguhxb wrote

Aah so its a ray shield. No, this i completely understand.

So, should we spring the trap?

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fastspinecho t1_iugnpx7 wrote

Keep in mind that a wall is mostly empty space. It's the electrons in the wall that stop you from walking through it.

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AlarmingAffect0 OP t1_iui1m2d wrote

… You can tell an insight is really clever when it's

  • illuminating
  • obvious in retrospect
  • would never have occurred to you to phrase it that way.

Thanks for the idea.

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rootofallworlds t1_iuihm0d wrote

More like a disintegration field. You know how atoms are round? Not in a magnetic field of 10^5 Tesla or more they aren't. The magnetic field is strong enough to distort the electron orbitals into narrow rods and ordinary molecules just fall apart. https://www.osti.gov/etdeweb/biblio/6961623 To borrow a phrase from Randall Munroe, "you would stop being biology and start being physics."

Oh, and the vacuum becomes birefringent - the speed of light depends on its polarisation.

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viliml t1_iuhbngp wrote

A cubic meter of water would have around 10^17 joules of energy... Wow that's a lot less.

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Beer_in_an_esky t1_iuhedux wrote

Yocto or yotta? Because a yocto joule is 10 to negative 24 J, which is not much at all.

Assuming you mean yotta though... That's terrifying. Amazing to think about, but utterly alien to any human-accessible frame of reference.

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