A NOTE ON SUPERSYMMETRIC D-BRANE DYNAMICS

We study the spin dependence of D-brane dynamics in the Green-Schwarz formalism of boundary states. In particular we show how to interpret i nsertion of supercharges on the boundary state as sources of non-unive rsal spin effects in D-brane potentials. In this way we find for a gen eric (D)p-brane, potentials going like upsilon(4-n)/r(7-p+n) correspon ding to interactions between the different components of the D-brane s upermultiplet. From the eleven dimensional point of view these potenti als arise from the exchange of field strengths corresponding to the gr aviton and the three form, coupled non-minimally to the branes. We sho w how an annulus computation truncated to its massless contribution is enough to reproduce these next-to-leading effects, meaning in particu lar that the one-loop (M)atrix theory effective action should encode a ll the spin dependence of low-energy supergravity interactions. (C) 19 98 Elsevier Science B.V.