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Neutrinos are subatomic particles with no electrical charge. Anti-matter has the same mass, spin, etc. as that of regular matter except the charge of anti-matter is opposite to that of the normal matter. As neutrinos don't have a charge, shouldn't both be the same thing?

Qmechanic
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    Does this answer your question? What exactly is an anti-neutrino? – Nihar Karve Feb 07 '21 at 10:02
  • Short answer: in pretty much all use cases they are not. You always get $W^-$ boson decay to lepton+anti-neutrino (not a neutrino) and $W^+$ to anti-lepton+neutrino. But neutrinos are so weird that people invent various ideas trying to explain their weirdness, this is one of those. There is no experimental proof that nu=anti-nu (but this cannot be fully excluded either). – Martino Feb 07 '21 at 14:02

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Nobody knows. Like photons and the Z boson, neutrinos could be their own anti-particle. It would be the only fermion[*] to be like that and would be called a Majorana fermion. However, neutrons are not their own anti-particles despite having no electric charge. Anti-neutrons are made of anti-quarks and annihilate with normal neutrons. Neutrinos could be either.

[*] Roughly, fermions are matters particle as opposed to a bosons, which are particles that mediates interactions.

Mark H
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  • I never understood and find confusing the concept of mediating the interaction, what does it mean exactly? That they appear in Feynman diagrams as virtual particles? That they appear in the Lagrangian, for example, as $q \bar{\psi} \gamma^\mu A_\mu \psi$ in the case of QED and the photon? – RenatoRenatoRenato Feb 07 '21 at 12:38
  • @RenatoRenatoRenato To say that, for example, photons mediate iteractions between electrons means that electrons would not be able to interact with each other if photons didn't exist. If photons didn't exist, electrons would pass by each other without deflecting their paths. This is similar to saying that it is only because electrons interact with the electromagnetic field that electrons can influence each other, if only indirectly through the EM field. Electrons can mediate interactions between photons through a 4-vertex electron-positron loop Feynman diagram. – Mark H Feb 10 '21 at 07:32
  • @RenatoRenatoRenato By contrast, gluons need no intermediary particle to interact with each other since they can interact directly. – Mark H Feb 10 '21 at 07:33
  • @RenatoRenatoRenato So, "the ability to appear as a virtual particle in a Feynman diagram" is a decent enough definition of an interaction mediator. Then, it's only because electrons appear much less frequently as virtual particles compared to photons that we call the former "matter" and the latter "force particles." Photon-photon scatterings are much, much less frequent than electron-electron scatterings. The categories do not have hard borders, but are based on relative frequencies of observation. – Mark H Feb 10 '21 at 07:36
  • @RenatoRenatoRenato This and other essays on that site are a great resource. – Mark H Feb 10 '21 at 07:38