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I know this sounds absurd, but after doing a little research I found that it may be possible (not entirely, but that is why I am asking about this here). I have been reading up on antimatter and quantum mechanics and I stumbled across this article on the subject of "creating antimatter with lightning". All lightning is is a stream of electrons travelling through a channel of ionised air. This is true of any electrical "arc". This brings me to my question. There is a trick which you can do with plasma globes (you can probably pick one up at a toy store quite easily), where you place a piece of aluminium foil on the top of the globe which attracts a stream of electrons via parasitic capacitance the the environment. However, I have put together a specialised spark-gap chamber which consists of two metal rods with sharp points ~0.2mm apart so that an arc jumps the gap. I attached a wire from the aluminium foil on the plasma globe to one of the electrodes, and I connected the other to ground. When I switched on the plasma globe, as expected, a small arc jumped the gap.

This experiment, while much less powerful (about 900,000 times less powerful) than lightning, does simulate it to some degree (with a constant flow of electrons with AC current instead of a small pulse of electrons with pulse current).

So if lightning can emit antiprotons and positrons, can my setup do the same?

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Lightning producing postitrons, i.e. the antiparticle of the electron can be seen here

In a collaborative study appearing in Nature, researchers from Japan describe how gamma rays from lightning react with the air to produce radioisotopes and even positrons—the antimatter equivalent of electrons.

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The gamma rays emitted in lightning have enough energy to knock a neutron out of atmospheric nitrogen,

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The final, prolonged emission was from the breakdown of now neutron-poor and unstable nitrogen atoms. These released positrons, which subsequently collided with electrons in annihilation events releasing gamma rays.

So it is not exactly pair creation. The energy of a lightning bolt is very large and gammas produced in order to create pairs of electron positrons would have to be at least 1MeV in energy.

The sparks in a spark gap in the lab do not have enough energy to generate gamma rays.

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  • $\begingroup$ Thankyou very much for your help. Have you got any ideas on how I could create 1MeV of energy (sorry if it's a silly question)? EDIT: 1MeV seems quite small, because my desktop lamp can output up to 3.745x10^20 eV (60W bulb), are you sure my spark gap cannot output 1MeV? $\endgroup$ Commented Jul 21, 2020 at 11:01
  • $\begingroup$ @sciencepiofficial One million volts is not "quite small"! You can make high voltage in various ways, eg a Tesla coil. But please be careful. As well as the hazards of high voltage, you need to make sure you aren't exposing yourself to unhealthy amounts of X-rays / gamma rays. $\endgroup$
    – PM 2Ring
    Commented Jul 21, 2020 at 11:10
  • $\begingroup$ @PM2Ring Thankyou for your concern, very much appreciated, however, in your answer you wrote 1 MeV (megaelectronvolt) not 1 Mv (megavolt). I will be sure to construct a lead container to do these experiments in future. Also, I have a tesla coil, but its just a slayer exciter sadly, and the impedance of the wire loads the voltage significantly. Perhaps I could attempt a van de graaf machine. Thanks again for your help, best wishes. $\endgroup$ Commented Jul 21, 2020 at 11:15
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    $\begingroup$ An electron volt is just the energy it takes to move an electron through a potential difference of 1 volt. To give an electron 1 MeV of energy you must have a pd of 1 million volts. $\endgroup$ Commented Jul 21, 2020 at 11:31
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    $\begingroup$ @sciencepiofficial the energy of a bit higher than 1 MeV has to be the energy of one gamma-ray/photon in order to have electron positron creation . en.wikipedia.org/wiki/Pair_production .The wats of your lamp are distributed among zillions of photons, because light emerges from the superposition of them. $\endgroup$
    – anna v
    Commented Jul 21, 2020 at 11:33

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