Can photons turn into neutrinos, similar to 'pair production' of electrons and positrons?

Question

Since neutrinos ate much lighter, and are their own antiparticles (Majorana), it should be much 'easier' than turning a photon into an electron-positron pair, correct?

Answer 1

Do you mean this type of diagram?:

with neutrino antineutrino outgoing?

It is not possible to first order, because the photon does not couple with the weak interaction and neutrinos only couple weakly. This means a loop ,as in photon photon interactiion would be necessary

(The left one is the virtual photon interacting with the field and allowing momentum conservation)

In addition to two electromagnetic vertices, there will be two weak vertices making the probability of interaction very very small, with respect to electron positron production.

Answer 2

Photons are the quanta of the electromagnetic interaction that couple via the electric charge to other fields. As neutrinos don't have any electric charge, photons cannot couple to them. So neutrinos cannot be generated in leading order out of photons (there might be a more complex process of higher order with intermediate states involving the weak interaction which makes it albeit rarely -- very rarely -- possible). Neutrinos have weak isospin, therefore they can interact with other matter only by weak interaction.

Answer 3

It is not known if neutrinos are Majorana fermions, but regardless even if they are not, it a pair of photons can in principle turn into a neutrino-antineutrino like in this diagram (on the left are the incoming photons, on the right are the resulting neutrino and antineutrino):

However, there is no tree-level process that would do the same thing (neutrinos cannot directly interact with photons), there has to be at least one loop, which makes this process suppressed. If two photons come close together, while it is possible that they turn into neutrino-antineutrino pair, the probability of it happening is absurdly small.