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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. Supergravily 281Under arbitrary variations, curvatures transform as8RM,.A = D,.8hMA — DM6h,.A. (8)Consider now a Yang—Mills type of action,1— IA4 0 A— ~ x “~L~’0 Rf~M~po- 91~’po~s..IABwhere 0 may depend on fields. Under local gauge transformations81 fd~x{RM,.’~?R (—fCB”Q~~”+ fBA”Q~’)+ RM,.AR,,,~8gaugeQ~~}. (10)Under arbitrary variations81 = Jd4x [4(D,.6hM~R~Q~T + RM,,ARP~B6QMAT]. (11)Partially integrating D,,6hMA and using that always fCD~~~h,.l)8hMC’ = _6h,,Ch,.DfDj~~one finds [308]forarbitrary variations= +R:Ro;A PO~T~48hMARPU8 3~Q~T]. (12)In the frequent case that Q~A~B~” is a constant times ~ the last three terms <strong>van</strong>ish, due to the Bianchiidentity D,.R,,~ ~°°’ = [D,.,[D0,D~]] ~°~ = 0.Finally we derive a theorem, which is useful when constraints on curvatures are not gauge invariantunder all local symmetries [523].Suppose one can solve a constraint RMA,.I~MA~= 0 for a given field hM 4°.Then hMA0 is a functional of other fields, and transforms no longer as (DM )A0, but according to the chainrule. However, after solving the constraint, its variation <strong>van</strong>ishes identically. Denoting by ô’ thedifference between the actual transformation law (using the chain rule) of hMA0 and the group lawo(gauge), one has the followingTheorem:(8’h,/~°) 8h8A, (RM,.”F~~) = [_.f~AR,,,B~C— R,,,,.” 8(gauge)]F~,”. (13)In particular, if the constraint is invariant under 8(,gauge), then hMA0, although no longer an independentgauge field, still transforms according to o(gauge) just as when it was an independent field.Using the formalism of this subsection, McDowell and Mansouri [308] showed that N = 1 supergravitywith cosmological constant follows from gauging OSp(1/4) and <strong>To</strong>wnsend and the author [517]showed the same for N = 2 and OSp(2/4). In the latter case, however, a term 84’~— FM,. ’ did not follow

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