Prove Spinor Identity in Arbitrary Dimension

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ismaili
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Actually, the original motivation is to check the closure of SUSY
[tex]\delta X^\mu = \bar{\epsilon}\psi^\mu[/tex]
[tex]\delta \psi^\mu = -i\rho^\alpha\partial_\alpha X^\mu\epsilon[/tex]
where [tex]\rho^\alpha[/tex] is a two dimensional gamma matrix, and [tex]\psi^\mu[/tex] ia s two dimensional Majorana spinor, the index [tex]\mu[/tex] in the two dimensional world is just some label of different fields.
I try to prove
[tex][\delta_1,\delta_2]\psi^\mu = 2i\bar{\epsilon}_1\rho^\alpha\epsilon_2\ \partial_\alpha\psi^\mu[/tex]
The following identity will help me a lot to prove the above formula,
[tex]\chi_A(\xi\eta) = - \xi_A(\eta\chi) - \eta_A(\chi\xi)\cdots(*)[/tex]
where [tex]A[/tex] is the spinor index and [tex]\chi,\xi,\eta[/tex] are three spinors.
My question is, I don't know how to prove (*), and I don't know those spinors in (*) are Majorana spinors or not, moreover, I even don't know those spinors live in what dimension!
Does anyone know how to prove (*)? or anyone know the reference which treat the algebra of spinors in arbitrary dimension? Thanks a lot!
 
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A:I think I have figured out the proof of (*). It is well known that, for two spinors \chi,\eta, the following holds\xi_A(\eta\chi) = \xi^B(\eta_A\chi_B + \eta_B\chi_A)\cdots(1)So, we can calculate the left side of (*) as\xi_A(\eta\chi) = - \xi^B(\eta_A\chi_B + \eta_B\chi_A)+ \eta_A(\chi^B\xi_B + \chi_B\xi^B)=- \xi^B(\eta_A\chi_B + \eta_B\chi_A)- \eta_A(\chi_B\xi^B)= - \xi_A(\eta\chi) - \eta_A(\chi\xi)which is exactly the right side of (*).