- #1

earth2

- 86

- 0

i'm stuck (yet again! :) )

I am somewhat confused by Dirac spinors [tex]u,\bar{u}[/tex]. Take the product (where Einstein summation convention is assumed):

[tex]u^r u^s\bar{u}^s[/tex] Is this the same as [tex]u^s\bar{u}^s u^r[/tex]? Probably not cuz u^r is a vector while the other thing is a matrix, right?

Cheers,

earth2