- #1

Hypochondriac

- 35

- 0

## Homework Statement

a)

Consider Glashow's model with general hypercharge assignments [tex]Y_L[/tex], [tex]Y_R[/tex], for the left-handed and right-handed fields, respectively. By demanding the correct electromagnetic couplings of the electron and neutrino to the photon, determine the ratio [tex]Y_L/Y_R[/tex].

[8 marks]

b)

Why are [tex]Y_L[/tex] and [tex]Y_R[/tex] not fixed by this requirement?

[2 marks]

## Homework Equations

None given, but I suspect these will be relevant

[tex] Y=2 \left( Q+T^3 \right) [/tex]

where Y is hypercharge, Q is electric charge and T^3 is the 3rd component of weak isospin.

and

[tex]\frac{1}{g^2}+\frac{1}{g'^2}=\frac{1}{e^2}.[/tex]

where g is the SU(2) coupling of the W fields, g' is the U(1) coupling of the B field and e is the electron charge?

## The Attempt at a Solution

Well I tried taking the ratio of the above formula for left and right, but came across problems. Firstly The neutrino doesn't couple with the photon. Secondly there are no right handed neutrinos (in this model). Lastly the neutrino doesn't have a charge. So I'm unsure if I'm even taking the right route or how the second equation comes into play.