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arXiv · 1804.00161

Commutative Geometry for Non-commutative D-branes by Tachyon Condensation

Tsuguhiko Asakawa·Goro Ishiki·Takaki Matsumoto·So Matsuura·Hisayoshi Muraki
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Abstract

There is a difficulty in defining the positions of the D-branes when the scalar fields on them are non-abelian. We show that we can use tachyon condensation to determine the position or the shape of D0-branes uniquely as a commutative region in spacetime together with non-trivial gauge flux on it, even if the scalar fields are non-abelian. We use the idea of the so-called coherent state method developed in the field of matrix models in the context of the tachyon condensation. We investigate configurations of noncommutative D2-brane made out of D0-branes as examples. In particular, we examine a Moyal plane and a fuzzy sphere in detail, and show that whose shapes are commutative $\mathbb{R}^2$ and $S^2$, respectively, equipped with uniform magnetic flux on them. We study the physical meaning of this commutative geometry made out of matrices, and propose an interpretation in terms of K-homology.

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Tsuguhiko Asakawa, Goro Ishiki, Takaki Matsumoto, So Matsuura, Hisayoshi Muraki. 2018-03-31. Commutative Geometry for Non-commutative D-branes by Tachyon Condensation. https://doi.org/10.1093/ptep/pty062

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