Physics Stack Exchange is a question and answer site for active researchers, academics and students of physics. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Assuming one has the following term in a Lagrangian:

$$ g (\overline{A_R} B_L)(\overline{C_R}D_L) $$

where A,B,C,D correspond to spin 1/2 Dirac particles and the subscripts $R$ and $L$ denote left- and right-handed particles. From what I remember does this correspond e.g. to the scattering process

$$ \tilde{A_R} + B_L \rightarrow \tilde{C_R} + D_L $$

where $\tilde{A_R}$ denotes the anti-particle of $A_R$ etc.

When 'moving around' the $B_L$ leg from the incoming to the outgoing part, one has to replace $B$ by its anti-particle $\tilde{B}$ if I remember correctly:

$$ \tilde{A_R} \rightarrow \tilde{B} + \tilde{C_R} + D_L $$

However, I wonder what the chirality of B is ?

share|cite|improve this question

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Browse other questions tagged or ask your own question.