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SUPERGRAVITY P. van NIEUWENHUIZEN To Joel Scherk 0370 ...

SUPERGRAVITY P. van NIEUWENHUIZEN To Joel Scherk 0370 ...

SUPERGRAVITY P. van NIEUWENHUIZEN To Joel Scherk 0370 ...

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P. <strong>van</strong> Nieuwenhuizen, Supergravity 373variables is diagonal in x and 0, and one finds indeed that for linear changes of integration variables thesuper Jacobian is equal to the superdeterminant.For nonlinear changes of integration variables, the super Jacobian is given by the result previouslygiven, or by the equivalent resultJ = det(3x”/ôx’) det’(3O”’/aO1, — 3O”’/9x~(Dx’/ax)1~3x”/301,) (10)and this result is derived in the next subsection.Finally we discuss how to exponentiate the superdeterminant. We claimsdetM= JdCexpiciJvieiC~, dC=fldC~dC~ (11)where C~denote commuting as well as anticommuting ghosts, namelyC~M,,C’2= C~A,,,.C2”+ C~B,,,.C2”+ C~CO,.C~ + C~’DO1,C~ (12)and C~’are anticommuting while C’ are commuting. The proof is based on translational invariance0= (—~(0M‘)“ fdC (exp(iC1MC2))= (—Y(0M 1)0 J dC[iM,1— M,kC~C~M,,]exp(iC1MC2)= fdC[istr(OM 1M)— C~OMIk C~]exp(1C 1MC2) (13)since interchanging [(8M 1)MC 2]’ and (C,My cancels the factor (—)‘ and yields an extra factor (—1)since ghosts have different statistics.WithI = fdC exp(iC1MC2) and str(0M’M) = —str(OMM~) (14)one finds thus thatOlnI=OlnsdetM (15)which is indeed what we intended to prove.One often rewrites the ghost action as1. (16)..~‘(ghost)= C*IM,1CIndeed, the Feynman rules are the same, but since (for example in Yang—Mills theory) M is not

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