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arXiv · hep-th/9712028

Toroidal Compactification Without Vector Structure

Edward Witten
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Abstract

Many important ideas about string duality that appear in conventional $\T^2$ compactification have analogs for $\T^2$ compactification without vector structure. We analyze some of these issues and show, in particular, how orientifold planes associated with $Sp(n)$ gauge groups can arise from T-duality and how they can be interpreted in F-theory. We also, in an appendix, resolve a longstanding puzzle concerning the computation of $\Tr (-1)^F$ in four-dimensional supersymmetric Yang-Mills theory with gauge group SO(n).

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Edward Witten. 1997-12-03. Toroidal Compactification Without Vector Structure. https://doi.org/10.1088/1126-6708%2F1998%2F02%2F006

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