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arXiv · 1903.00487

Gepner-like boundary states on $T^4$

M. Schnabl·J. Vosmera
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Abstract

We present exact expressions for elementary boundary states which describe D-branes preserving 16 or fewer supercharges in type II superstring compactified on certain self-dual 4-tori. While being manifestly superconformal, our boundary states are not a priori required to satisfy the usual free-field gluing conditions along the internal directions of the 4-tori. Our calculations proceed along the lines of Gepner's construction by recasting the $\mathcal{N}=(2,2)$ worldsheet sigma model on the 4-tori in terms of $\mathcal{N}=2$ minimal models. Imposing general permutation gluing conditions on the $\mathcal{N}=(2,2)$ generators is shown to yield various stable and unstable D-branes, where the stable ones include the known 1/2-BPS and 1/4-BPS bound states of D$p$-branes, as well as new non-BPS D-branes, which do not carry RR charges.

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M. Schnabl, J. Vosmera. 2019-03-01. Gepner-like boundary states on $T^4$. https://arxiv.org/abs/1903.00487

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