Has it been experimentally verified, that electrons feel gravity?
Yes. The fact that the hydrogen atom weighs more that the hydrogen ion shows this.
Some atoms/ions are Fermions, some are Bosons, and they all seem to fall. Bosonic ions are abserved to fall in cold cavity experiments.
For some reason I thought that it would be impossible to detect a charge of some material by its weight (judging by intuition), but in fact I never did check this with any calculations.
What are typical charges that we can handle?
The electrons weight about 6*10^(-4) times the weight of protons, so if (in a hypothetical case) all electrons could be sucked out of some material, sure it would be showing on a weight scale. But I have no idea what kind of ratios of electrons and protons we are talking about in reality, when charging some material.
The title "gravitation on fermions" was poorly put..... in fact it was a mistake. I should have said "gravitation on leptons". Anyway, I'm interested in electrons and nucleus mostly.
Yes. It was a big mistake! Surely I wasn't thinking about a possibility of odd number of fermions switching the gravity off! I was thinking about the way how the common leptons are very light, and how the heavier ones appear only in fast particle collisions. And I forgot that the heavy quarks are fermions too... I don't know why I confused concepts "fermions" and "leptons"....
I wouldn't mind if some mentor would change the title (please). It probably wouldn't confuse the thread, since this response to Mentz144's comment would explain it.
I guess I should have tried to answer your question not your title. I think electron accelerator designers and CRT designers would know whether electrons fell like other matter (?). But I've not heard of an experiment to test this. There is no reason to suppose not.
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