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arXiv · hep-th/9801183

Scale independent spin effects in D-brane dynamics

Jose F. Morales·Claudio A. Scrucca·Marco Serone
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Abstract

We study spin interactions between two moving D-branes using the Green-Schwarz formalism of boundary states. We focus our attention on the leading terms for small velocities v, of the form v^{4-n}/r^{7-p+n} (v^{2-n}/r^{3-p+n}) for p-p (p-p+4) systems, with 16 (8) supercharges. In analogy with standard G-S computations of massless four-point one-loop amplitudes in Type I theory, the above terms are governed purely by zero modes, massive states contributions cancelling as expected by the residual supersymmetry. This implies the scale invariance of these leading spin-effects, supporting the relevant matrix model descriptions of supergravity interactions; in this context, we also discuss similar results for more general brane configurations. We then give a field theory interpretation of our results, that allows in particular to deduce the gyromagnetic ratio g=1 and the presence of a quadrupole moment for D0-branes.

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Jose F. Morales, Claudio A. Scrucca, Marco Serone. 1998-08-31. Scale independent spin effects in D-brane dynamics. https://doi.org/10.1016/s0550-3213(98)00609-9

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