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arXiv · 1904.06714

Open exceptional strings and D-branes

Chris D. A. Blair
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Abstract

We study D-branes in the extended geometry appearing in exceptional field theory (or exceptional generalised geometry). Starting from the exceptional sigma model (an $E_{d(d)}$ covariant worldsheet action with extra target space coordinates), we define open string boundary conditions. We write down Neumann and Dirichlet projectors compatible with the preservation of half-maximal supersymmetry by the brane (building on previous work on the definition of generalised orientifold quotients in exceptional field theory). This leads to a definition of D-branes, plus their S-duals, as particular subspaces of the exceptional geometry, and provides an opportunity to study D-branes in U-fold backgrounds.

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Chris D. A. Blair. 2019-04-14. Open exceptional strings and D-branes. https://doi.org/10.1007/jhep07(2019)083

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