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Tachyon Condensation on Noncommutative Torus

I. Bars·H. Kajiura·Y. Matsuo·T. Takayanagi
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Abstract

We discuss noncommutative solitons on a noncommutative torus and their application to tachyon condensation. In the large B limit, they can be exactly described by the Powers-Rieffel projection operators known in the mathematical literature. The resulting soliton spectrum is consistent with T-duality and is surprisingly interesting. It is shown that an instability arises for any D-branes, leading to the decay into many smaller D-branes. This phenomenon is the consequence of the fact that K-homology for type II von Neumann factor is labeled by R.

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I. Bars, H. Kajiura, Y. Matsuo, T. Takayanagi. 2000-10-13. Tachyon Condensation on Noncommutative Torus. https://doi.org/10.1103/physrevd.63.086001

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