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Would antimatter in a solid form, anti-lithium for example, be easier to store than gaseous anti-hydrogen or just plain positrons?

Fluffy
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  • Dunno how much easier it is, but you could e.g. use magnetic levitation to suspend a very low temperature sample of anti-Li (or other superconductor). You need to make sure it remains at a temperature lower than $T_C$, and the magnetic field doesn't shut off, otherwise the sample drops onto matter and... – Ruslan Jan 01 '19 at 10:25

2 Answers2

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We don't know how to make solid chunks of antimatter. However, if we could do it, then it should be much easier to store a solid chunk than a gas.

I can imagine several different ways to keep the chunk suspended in a vacuum: via diamagnetic repulsion, electromagnetic suspension, electrostatic repulsion, or photon pressure.

The temperature would need to be kept close to absolute zero, because most solids have a finite vapor pressure and any atoms that floated away from the chunk would annihilate as soon as they reach the normal-matter container.

S. McGrew
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The problem with antimatter, regardless of its phase, is that it annihilates into light as soon as it comes into contact with matter.

So you always have to make sure that your contained in empty (there is a good vacuum inside), and that the antimatter does not touch the walls.

I don't actually know how antimatter is usually stored, if anyone has ever done it. But ions and neutral atoms can be trapped (Pauli, TOP, optical dipole traps for example), and the principles behind these should also be valid for antimatter.

SuperCiocia
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    The electrostatic repulsion between the anti-lithium and the walls wouldn't stop it from touching the walls? – Fluffy Apr 25 '17 at 23:09
  • Lithium is an atom, so would anti-lithium, so it's neutral overall? Also, you cannot make a trap with only electric fields, it'd be unstable. – SuperCiocia Apr 26 '17 at 09:09
  • To specify, the repulsion that prevents objects from passing through each other wouldn't separate the anti-lithium from the walls enough that they wouldn't annihilate? – Fluffy Apr 26 '17 at 15:37
  • Ah. Ok I don't know enough about this. I don't know how close you have to be for annihilation to happen. But it's all probabilistic so the closer you are, the more likely it'll happen. Also, the positron in the anti-Lithium atom and the electron in the walls now have distinct quantum numbers (charge is differnet), so Pauli exclusion does not apply. This is what causes the kind of repulsion you're talking about, the electrons in my feet's atoms cannot be in the same place as the ground outer electrons because of Pauli. – SuperCiocia Apr 26 '17 at 18:38
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    When 2 objects touch each other, it's their electrons that come into contact. Anti-lithium would have anti-electrons, so they will attract each other and go kablooee!! – hdhondt Nov 30 '18 at 04:20
  • @Fluffy since it is mostly the Pauli exclusion principle that prevent object from passing through each other, you can't really get the repulsion you want because positrons and electrons do not have exclusion – KF Gauss Nov 30 '18 at 04:56
  • The matter-antimatter annihilation of composite particles is messy, it doesn't directly go to photons. See https://physics.stackexchange.com/a/244027/123208 (Also, antiprotons will annihilate with neutrons, and vice versa). – PM 2Ring May 03 '19 at 01:13