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Topological Charge of U(1) Instantons

Furuuchi Kazuyuki
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Abstract

Non-singular instantons are shown to exist on noncommutative R^4 even with a U(1) gauge group. Their existence is primarily due to the noncommutativity of the space. The relation between U(1) instantons on noncommutative R^4 and the projection operators acting on the representation space of the noncommutative coordinates is reviewed. The integer number of instantons on the noncommutative R^4 can be understood as the winding number of the U(1) gauge field as well as the dimension of the projection on the representation space.

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Furuuchi Kazuyuki. 2000-10-02. Topological Charge of U(1) Instantons. https://doi.org/10.1143/ptps.144.79

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