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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. Supergravitv 261For N = 1 supergravity, one finds that the R2-type invariants as far as kinetic terms are concerned,are given by (either by the Noether method or by the tensor calculus)~2’2=R2+R .yJy.R—4(~S)2—4(a,,P)2+4(a•A)2= (R,~,,2—~R2)—~I~(L16,W — 9,,~9,.XR”...~“y R)—~(8,~A,. —(2)For the gauge action we have, of course,~ =R+ifr R+~(S2+F2—A~,).<strong>To</strong> find the physical states in this system, it is ad<strong>van</strong>tageous to use spin projection operators in order todescribe the terms bilinear in fields. In this way one finds with (see subsection 1.13)RM,. = ~(EhM,. — h,,,. — h,.,, + h.,,,.) = ~(F2+ \/~p0.ts + PO.S)h,,,,,eR = L1O,~,.h,,,,.— ~h,,,.(L~F2— 2LIJFO.s),0.h,,,,. (3)R 2 = 3h(LI2P°”)h, R,~,.2—~R2 = ~h(LIFF2)hthat the graviton propagator becomes P2(~yE+ ~$L12Y’+ FOs(_~yE+ 3aE2)~’,so that the gravitonstates are:(i) a massive spin 2 with M2 = —~yIJ3and ghost if /3 0(iii) a massive spin 0 with M2 = ~y/a and physical if a > 0.For the gravitino part one finds (see subsection 1.13)4’ R = ~(P312— 2P1”2~)J4,~ yJY• R = ~121i(LIP1”2”)J4’ (4)4i~,LI&”~(R,, —~y,;y. R)~(EP3”2),~’4’that the propagator becomes —P3”2[J(f3L1 + ~y)]’ + P~’2[J(aEJ+ ~y)]~. Thus the gravitino states are:(i) two massive spin 3/2 with M2 = —~y//3and both ghosts if /3 0(iii) two massive spin 1/2 with M2 = i1syla and both physical if a > 0.Note that at E = 0 both P2 and ~O.S(and F3”2 and Pl~2~s) define the usual tetrad and gravitino states.<strong>To</strong> check these results, note that ~2’3 contains only highest spin (as expected from a conformalinvariant) while ~2’,yields the usual spin 2 and 3/2 propagators if sandwiched between conservedcurrents. The relative factors between the graviton and gravitino projection operators in ~2’2and ~2’3arethe same.If one considers the spin 1 and spin 0 states of the auxiliary fields (which propagate in 2’2 and 2’3!)one finds for the A,,, propagator P’(~y+ ~/3[])~’+F°(~y — 4aLJ). For the fields S and P one finds twomore massive spin 0 states. All these fields clearly constitute(i) the usual (2,~)massless physical multiplet;

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