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Closed string exchanges on $C^2/Z_2$ in a background B-field

Swarnendu Sarkar
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Abstract

In an earlier work it was shown that the IR singularities arising in the nonplanar one loop two point function of a noncommutative ${\cal N}=2$ gauge theory can be reproduced exactly from the massless closed string exchanges. The noncommutative gauge theory is realised on a fractional $D_3$ brane localised at the fixed point of the $C^2/Z_2$ orbifold. In this paper we identify the contributions from each of the closed string modes. The sum of these adds upto the nonplanar two-point function.

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Swarnendu Sarkar. 2006-02-15. Closed string exchanges on $C^2/Z_2$ in a background B-field. https://doi.org/10.1088/1126-6708%2F2006%2F05%2F020

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