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I'm going to be brief, I just saw a Discovery Channel show that showed a lot of interesting phenomena around lightning (like elves, how cool is that(!)), and got me wondering.

1) Thinking of lightning as a purely mechanical phenomenon, I would think the elves are the "other side of the momentum balance". What I mean is this: somewhere in some cloud formation, an event happens that triggers a lightning flash. This means a ton of electrons (and other, associated particles) that start a very fast journey to the surface of the Earth. Their momentum must be balanced by particles going in the opposite direction, hence elves. Am I right?

2) Taking this further, is it possible that the "trigger" for the lightning flash could be atomic/molecular fusion forced by extremely high electrical fields, that may only exist for a nanosecond, causing a ton of energy to be transferred to the electrons around the atoms/molecules, and we have lightning. I would then think of the energy necessary to force the fusion to occur as a quantum fluctuation as in $$\Delta E \Delta t \leq \hbar$$

3) Is every arc caused by a particle collision, somewhat like in a particle accelerator? It seems logical to me: there are more than enough particles in the air to collide with, and all the light could well be some form of Brehm or Cherenkov radiation.

The question I seem to be asking is where to find good scientific theory/information about lightning. Some say we know a lot about it, but I haven't found any good papers explaining it. I have a pretty good background in physics (1st year Master student) and am not afraid of serious literature. Thanks!

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Why the downvote? – rubenvb May 27 '11 at 22:34
rubenvb, can you provide any reference for your suggestion that nuclear fusion is involved in lightning? Also what do you mean by molecular fusion? The existing answers haven't addressed this part, I guess because it's not clear where this idea is coming from. (I am not the one who downvoted.) – Dan Brumleve May 28 '11 at 5:21
have a look at this article which correlates gamma rays with lightning.… also – anna v May 28 '11 at 7:18
@Dan: the idea comes from the dark corners of my mind, and the comment made in the documentary about the fact that the clouds producing the lightning should not be able to produce enough energy to account for the energy in a lightning bolt – rubenvb May 28 '11 at 10:16
""the clouds producing the lightning should not be able to produce enough energy to account for the energy in a lightning bolt "" Ahh, what is a "lightning bolt" ? – Georg May 28 '11 at 12:35

no, that is not how momentum conservation works; the cloud gain a counter moment briefly which is transferred later to the earth, triggering vibrational modes but making net earth momentum conserved. no need to reach a balance. It might be plausible however, that positive ions travel in the opposite direction than electrons to balance the same electric potential, so the elves are probably these bursts of plasma ions moving upward

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Correct, no momentum considerations here. Elves as accelerated plasma ions is correct. – Bill Slugg May 28 '11 at 3:52

Yes and no. There is a large scale movement back and forth of electrons, but it is not their mechanical momentum that is causing the strange phenomena, it is this HUGE displacement of charge over a very long distance causing the problem. The vertical movement of ice crystals rubs electrons off and transports them to the bottom of the cloud. At the top of the cloud is a huge ball of missing electrons thus a huge positive charge exists here. With massive balls of separated charge displaced over large distances you have the attendant very large electric fields.

The electric fields extend far above the thunderstorms and into space. In the upper reaches of the atmosphere there are few atoms per unit volume and quite a few ions. Mix those with very large electric fields and strange things happen.

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i also thought of the same phenomenon. I am in location where I see lightening almost every day and academically I am an electrical engineer. I found that almost all formulas of Lightening have proved wrong. There had been silent lightening, lightening at lower heights than higher grounds, lightening on flat surfaces than elevated tips. Lightening when there is no wind between clouds and also when there is wind there is no lightening. Lightening for continuous fifteen minutes and so on. So they all prove that lightening may not be due to charge formation in clouds. On seeing that I wanted to relate one thing. There may be some subatomic/ atomic substances like that of Hydrogen that may be getting closer together in the clouds. It might be getting more than that like of critical mass. There would few electric ions formation which would trigger the operation of H+ ions or neutrons slowly moving in the cloud. This neutron would be initiating the fusion/ atomic reaction which is resulting in lightening. Please note that this is just observation and has no mathematical proof. but this thing satisfies the reason of lightening. Lightening is sudden discharge of light (may be accompanied by sound) in air and especially clouds.

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This isn't a place to pimp your personal theories and working ideas. It seems like you have some reasonable ideas in here so you should turn some of them into questions on the site. – Brandon Enright Jun 1 '13 at 22:14

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