Board Thread:Questions and Answers/@comment-5780397-20151222190152/@comment-25814498-20151225221610

It's a nice theory, but if all Hatsu techniques were based off of changing the properties of atoms in air, it would have been more evident in the show. Imagine Bonolenov and his Battle Cantabile: Jupiter for instance. The amount of air that would need to be absorbed in order to create a body of that magnitude would be immense to the point of absurdity, and this doesn't explain why Non nen users can't see aura if it's simply air with special properties.

Like I said, it's possible that Nen is some form of new particle that affects other forms of matter in ways the characters simply regard as life force or aura, somply because they can't explain it in any other way. Or, it could be that since they come from a different universe, Nen users in the hunter x hunter world can hold extremly high levels of chemical energy in their cells, which when they want to expend, is transformed into aura inside their bodis, before being released through the pours Wing spoke of when explaining Nen to Gon and Killua.