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On the ADHM construction of noncommutative U(2) k-instanton

M. Lagraa
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Abstract

The basic objects of the ADHM construction are reformulated in terms of elements of the $A_θ(R^4)$ algebra of the noncommutative $R_θ^4$ space. This new formulation of the ADHM construction makes possible the explicit calculus of the U(2) instanton number which is shown to be the product of a trace of finite rank projector of the Fock representation space of the algebra $A_θ(R^4)$ times a noncommutative version of the winding number.

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M. Lagraa. 2006-02-15. On the ADHM construction of noncommutative U(2) k-instanton. https://doi.org/10.1103/physrevd.73.065021

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