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Tachyon Condensation on Fuzzy Sphere and Noncommutative Solitons

Yasuaki Hikida·Masatoshi Nozaki·Tadashi Takayanagi
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Abstract

We study a brane-antibrane system and a non-BPS D-brane in SU(2) WZW model. We first discuss the tachyon condensation using the vertex operator formalism and find the generation of codimension two D-branes after the condensation. Our result is consistent with the recent interpretation that a D2-brane is a bound state of D0-branes. Then we investigate the world volume effective theory on a non-BPS D-brane. It becomes a field theory on the ``fuzzy sphere'' when the level is sent to infinity. The most interesting feature is that there exist the noncommutative tachyonic solitons and we can identify them with D0-branes. We also discuss the brane-antibrane system from the world volume point of view and comment on the relation to the noncommutative version of the index theorem.

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Yasuaki Hikida, Masatoshi Nozaki, Tadashi Takayanagi. 2000-12-06. Tachyon Condensation on Fuzzy Sphere and Noncommutative Solitons. https://doi.org/10.1016/s0550-3213(00)00693-3

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