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You cannot "see" a flash if the eye receives no stimulus even though the brain is directly hit by a neutrino and it would be impossible to detect it because: 1) There is no receptor of this sort in the brain. 2) A neutrino has an extremely tiny mass. I can assure you that if the human body was capable of detecting an individual subatomic particle colliding ...

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The cross-section for neutrino interactions is energy dependent. For solar neutrinos at $\sim 0.4$ MeV, which would likely dominate any neutrinos likely to interact (the cosmic background neutrinos have way low energies) , the cross-sections are $\sigma \sim 10^{-48}$ m$^2$, for both leptonic processes (elastic scattering from electrons) and ...

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If you are that fast in detecting light, you are seeing cosmic ray muons. They are charged and leave an ionizing track in anything they cross and Cerenkov light. in liquid, and the eye is mainly liquid. They are the most numerous energetic particles arriving at sea level, with a flux of about 1 muon per square centimeter per minute. This can be ...

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This definitely is not a neutrino. Neutrinos are hard to detect because they are light, quick, and have no charge, making them usually pass through matter. We build giant machines to detect single neutrinos. The chances of this happening extremely low.

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The short answer to your question is that, out of the known non-gravitational forces, neutrinos only respond to the weak force, but the weak force only acts on left-handed particles, so right-handed neutrinos would not respond to any of those forces. As for the paper by Arkani-Hamed et al, the idea is that the non-gravitational forces only act within the ...

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You say about Majorana fermions: "From this I would argue that they need to have all quantum numbers equal to zero." which is not true. Charge conjugation is defined on Dirac spinors as $\psi^c := \mathrm{i}\gamma^0\gamma^2\bar\psi^T$. Being Majorana means $\psi^c = \psi$. While this would imply the spinor has zero electric charge (and zero all other ...

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There is no well established theory predicting the neutrino mass (even if of Majorana type). A particle is its own anti-particle if the field describing the particle is a real field. That means obviously that the electric charge is 0 but not necessarily that other charges are zero. For instance, if the neutrinos are Majorana neutrinos, they would still have ...

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In standard model, the mass of a particle can be explain by either Dirac or Weyl equation. The first thing is that neutrinos are can't be described by any of the above equations (Dirac equation or Weyl equation) in the standard model because no right handed neutrinos are observed. Dirac equation needs four spinors to explain the mass of any particle. But in ...

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