D-Sphalerons and the Topology of String Configuration Space
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چکیده
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 has non-trivial homotopy groups πk for all k even (odd).
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تاریخ انتشار 2000