Is There Anything Smaller Than an Electron Neutrino?

[qsefthuko66]

Do you know a particle smaller than an electron neutrino? An electron neutrino is far by the smallest particle I know! Do you know something smaller than that?

 

[mathman]

The electron neutrino has the smallest non-zero mass of all known particles.

 

[Parlyne]

The electron neutrino has the smallest non-zero mass of all known particles.

The electron neutrino doesn't have a well-defined mass. It's a superposition of the three neutrino mass eigenstates, the lightest of which is the lightest know fermion. However, it is not know whether the lightest neutrino has a non-zero mass.

 

[chrispb]

The electron neutrino doesn't have a well-defined mass. It's a superposition of the three neutrino mass eigenstates, the lightest of which is the lightest know fermion. However, it is not know whether the lightest neutrino has a non-zero mass.

If the lightest neutrino had zero mass, then the determinant of the mass matrix would be 0 and neutrino oscillations would not occur.

 

[Parlyne]

If the lightest neutrino had zero mass, then the determinant of the mass matrix would be 0 and neutrino oscillations would not occur.

You are correct that the determinant would be 0; however, I believe that you are incorrect that that would eliminate oscillations. As far as I know, the only ways to prevent oscillations are to set mixing angles to 0 or to make neutrino mass states degenerate. Neither of these possibilities are guaranteed by a 0 determinant.

 

[chrispb]

You are correct that the determinant would be 0; however, I believe that you are incorrect that that would eliminate oscillations. As far as I know, the only ways to prevent oscillations are to set mixing angles to 0 or to make neutrino mass states degenerate. Neither of these possibilities are guaranteed by a 0 determinant.

Ah, yes, it's not m^2 that factors into the calculation, but delta m^2. My mistake.

 

[rvsupply]

oh! really is it true the only ways to prevent oscillations are to set mixing angles to 0 or to make neutrino mass states degenerate

 

[rvsupply]

is it hard to mix them?

 

[rvsupply]

any idea of mixing angles to 0 or to make neutrino mass states degenerate i think this easy if you have a great trainer...