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Non-commutative (D)-instantons

Marco Billo·Marialuisa Frau·Stefano Sciuto·Giuseppe Vallone·Alberto Lerda
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Abstract

We study systems of D3 and D(-1) branes in a NS-NS magnetic background and show that, when the brane configuration is stable, the physical degrees of freedom of the open strings with at least one end-point on the D-instantons describe the ADHM moduli of instantons for non-commutative gauge theories. We also prove that disk diagrams with mixed boundary conditions are the sources for the classical profile of the non-commutative gauge instantons in the singular gauge. We finally compare the string theory description in a large distance expansion with the non-commutative ADHM construction in the singular gauge and find complete agreement at perturbative level in the non-commutativity parameter.

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Marco Billo, Marialuisa Frau, Stefano Sciuto, Giuseppe Vallone, Alberto Lerda. 2005-12-16. Non-commutative (D)-instantons. https://doi.org/10.1088/1126-6708%2F2006%2F05%2F069

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