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there are many experiments that put different contraints on the neutrino masses. Here is a good collection from the particle data group.

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Yes, neutrinos should obey Fermi-Dirac statistics and yes, the Pauli Exclusion Principle should operate for neutrinos. But let's examine how dense the neutrino population has to be for this to be important. The Fermi momentum is given by $$p_F = \left( \frac{3}{8\pi}\right) h n_{\nu}^{1/3}$$ where $n_{\nu}$ is the neutrino number density. In order to be ...

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I suppose the question refers to the scenario that there is an isotropic radiation of neutrinos in universe and that the part of this radiation that passes through earth before it penetrate our bodies is somewhat weaker than the corresponding radiation from above and that this difference give rise to a presumable tiny force downward, that is a (tiny) part of ...

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Even if neutrinos were massless, which they aren't, they would still be affected by gravity because of their energy content. For example light is composed of massless photons but these can and are still affected by gravity because of $E=mc^2$ But that's null because we know neutrinos are massive because they oscillate.

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It would help if you gave some context. Is there any evidence, or even theoretical work, that suggests neutrinos are not affected by gravity? I suppose you could argue that the similar arrival times of photons and neutrinos from SN 1987A was evidence that neutrinos and photons are following the same path through spacetime and both being "gravitationally ...

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All processes involving neutrinos are weak mediated because neutrinos have zero electromagnetic and color charge. At tree level, all processes involving a $\nu + \bar\nu$ final state without other debris involve a time-like $Z^0$ (except neutrino NC scattering) which implies the annihilation of a particle/antiparticle pair (and will be suppressed relative ...

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I'm speculating here, basically looking at two considerations. Considering you used the term "radioactive decay" I'm going to look at this from a gross nuclear viewpoint rather than a particle/subnuclear viewpoint. If a nucleus is in it ground state, it would have no mode to lose energy without changing Z. So, in this case, no. If a nucleus is not in its ...

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Neutrinos are elementary particles in the standard model, which model has been very successful in organizing all the data we have on elementary particle interactions in a mathematically rigorous form. In the table for elementary particles neutrinos are considered stable, in contrast to taus and muons, as quantum number and energy conservation, within the ...

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