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arXiv · hep-th/0001143

D-Sphalerons and the Topology of String Configuration Space

Jeffrey A. Harvey·Petr Horava·Per Kraus
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Abstract

We show that unstable D-branes play the role of ``D-sphalerons'' in string theory. Their existence implies that the configuration space of Type II string theory has a complicated homotopy structure, similar to that of an infinite Grassmannian. In particular, the configuration space of Type IIA (IIB) string theory on $\R^{10}$ has non-trivial homotopy groups $π_k$ for all $k$ even (odd).

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Jeffrey A. Harvey, Petr Horava, Per Kraus. 2000-01-31. D-Sphalerons and the Topology of String Configuration Space. https://doi.org/10.1088/1126-6708%2F2000%2F03%2F021

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