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Is a classical description of stable non-BPS D-branes possible?

M. Bertolini·P. Di Vecchia·M. Frau·A. Lerda·R. Marotta·R. Russo
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Abstract

We study the classical geometry produced by a stack of stable (i.e. tachyon free) non-BPS D-branes present in K3 compactifications of type II string theory. This classical representation is derived by solving the equations of motion describing the low-energy dynamics of the supergravity fields which couple to the non-BPS state. Differently from what expected, this configuration displays a singular behaviour: the space-time geometry has a repulson-like singularity. This fact suggests that the simplest setting, namely a set of coinciding non-interacting D-branes, is not acceptable. We finally discuss the possible existence of other acceptable configurations corresponding to more complicated bound states of these non-BPS branes.

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M. Bertolini, P. Di Vecchia, M. Frau, A. Lerda, R. Marotta, R. Russo. 2000-07-25. Is a classical description of stable non-BPS D-branes possible?. https://doi.org/10.1016/s0550-3213(00)00558-7

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