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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 327Let us see what its field equations are. From sdet V = expstr In V one has5I=Jd4xd4O(VA~~5V 4A)(_)*2sdetV. (20)but the variations SVA~must respect the torsion constraints. From the definition of TBCA given earlier itis straightforward to derive (using the index convention of page 313)STBCA = !DHA — 1( — )BCD HA + TBCDHDA H°TDCA + ( )BCHD TDBA + QBC — ( )13C1)A1BCwhere HAB = VAASVAB while ‘= VBA&,bACAi ‘~A(B±11)8AVfJ +U) VII ~PAB1jB~ A (22LJ4Vfl —11 Ti II .~VA — ~14 VA — (PAAThe signs follow by first making the purely bosonic sector agree, and then moving indices such that theyappear on the left and right hand side in the same order. As a consequence, the Leibniz rule8’5(vAuA) = (8’5vA)uA + (_)AAvA8u (23)(21)holds also for covariant derivatives. Of course the ~spin connections h~m~(compare with (18)).One can solve this equation for HAB and finds thencan be expressed in terms of the earlier definedSJd4xd4osdet V=fd4xd40sdet V[VtmTma” _RU_R*U*1 (24)where vtm and U are arbitrary superfields. Since Tm,,” is proportional to Gm, one has as field equationsGmRO. (25)These are the N = 1 superspace supergravity field equations. Since, as we shall show presently,R = S + iP +... and G~= A~X~ they agree with the ordinary space approach.<strong>To</strong> show how the Wess—Zumino approach can reproduce the ordinary space approach we establishthe bridge by requiring compatibility as before [577].For any superfield V (with any number of tangent space indices) a transformation S is defined bysv = ~DA V = ~A VAA 8A V+ ~~!hAmn(~X~,,V). (26)Hence, S is the sum of a general coordinate transformation with field-dependent parameter e” = ~A VAAand a local Lorentz transformation with field-dependent parameter ~AhAmn The ad<strong>van</strong>tage of thisdefinition is that the commutator is proportional to only supertorsion and super curvaturer.g.~1~z—~B~r1~B~A(0 mnly IT CL 1, 2J 525T1[ A, BfS2S1~ AB 2 mn AB C (27)

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