nLab Sugimoto string



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A non-anomalous tachyon-free non-supersymmetric string theory obtained from an orientifold projection of the Type IIB string.

First described in Sugimoto (1999), this string theory can be obtained from introducing an orientifold plane O9 +O9^+ along with 32 D 9 ¯ \overline{D9} anti D-branes. The resulting theory has the USp(32)USp(32) compact symplectic group as a gauge group. This is in contrast with the Type I string, which can be obtained from a O9 O9^- plane and 32 D9D9 branes, with a gauge group SO(32)SO(32).


The orientifold projection leading to this string was first described in:

Last revised on October 28, 2023 at 14:51:03. See the history of this page for a list of all contributions to it.