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arXiv · hep-th/0210206

NCOS and D-branes in Time-dependent Backgrounds

Rong-Gen Cai·Jian-Xin Lu·Nobuyoshi Ohta
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Abstract

We study noncommutative open string (NCOS) theories realized in string theory with time-dependent backgrounds. Starting from a noncommutative Yang-Mills theory (NCYM) with a constant space-space noncommutativity but in a time-dependent background and making an S-dual transformation, we show that the resulting theory is an NCOS also in a time-dependent background but now with a time-dependent time-space noncommutativity and a time-dependent string scale. The corresponding dual gravity description is also given. A general SL(2,Z) transformation on the NCYM results in an NCOS with a time-dependent time-space noncommutativity and a constant space-space noncommutativity, and also in a time-dependent background.

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Rong-Gen Cai, Jian-Xin Lu, Nobuyoshi Ohta. 2002-11-19. NCOS and D-branes in Time-dependent Backgrounds. https://doi.org/10.1016/s0370-2693(02)03023-x

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