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arXiv · hep-th/0312003

Moduli Space of Unstable D-branes on a Circle of Critical Radius

Ashoke Sen
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Abstract

We study the moduli space of the boundary conformal field theories describing an unstable D-brane of type II string theory compactified on a circle of critical radius. This moduli space has two branches, -- a three dimensional branch S^3/Z_2 and a two dimensional branch described by a square torus T^2. These two branches are joined along a circle. We compare this with the moduli space of classical solutions of tachyon effective field theory compactified on a circle of critical radius. This moduli space has a very similar structure to that of the boundary conformal field theory with the only difference that the S^3 of the S^3/Z_2 component becomes a deformed S^3. This provides one more indication that the tachyon effective field theory captures qualitatively the dynamics of the tachyon on an unstable D-brane.

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Ashoke Sen. 2003-12-13. Moduli Space of Unstable D-branes on a Circle of Critical Radius. https://doi.org/10.1088/1126-6708%2F2004%2F03%2F070

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