# Charge raising weak current

## Main Question or Discussion Point

I am baffled by what exactly it means to have the following (ingoing, outgoing) lepton pair configuration: $$(0,\nu_L e_R^+)$$ and $$(e_L^- \bar{\nu}_R,0)$$

This specific question was asked in Halzen and Martin exercise 12.3.

How is it possible to have 0 in going particles and a neutrino and electron going out? I know that an ingoing right-handed antineutrino is the same as a out going lefthanded neutrino, etc, but just trying to grasp what exactly this $$(0,\nu_L e_R^+)$$ and $$(e_L^- \bar{\nu}_R,0)$$ configuration means physically is confusing.

Did Halzen and Martin specifically give this example just to show one can switching ingoing and outgoing particles without looking at its physical consequences?