Metric and coupling reversal in string theory

M. J. Duff; Jussi Kalkkinen

doi:10.1016/j.nuclphysb.2006.10.016

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arXiv · hep-th/0605274

Metric and coupling reversal in string theory

M. J. Duff·Jussi Kalkkinen

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Abstract

Invariance under reversing the sign of the metric G_{MN}(x) and/or the sign of the string coupling field H(x), where = g_s, leads to four possible Universes denoted 1,I,J,K according as (G,H) goes to (G,H), (-G,H), (-G,-H), (G,-H), respectively. Universe 1 is described by conventional string/M theory and contains all M, D, F and NS branes. Universe I contains only D(-1), D3 and D7. Universe J contains only D1, D5, D9 and Type I. Universe K contains only F1 and NS5 of IIB and Heterotic SO(32).

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M. J. Duff, Jussi Kalkkinen. 2006-08-16. Metric and coupling reversal in string theory. https://doi.org/10.1016/j.nuclphysb.2006.10.016

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