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arXiv · hep-th/0112211

The Seiberg-Witten prepotential and the Euler class of the reduced moduli space of instantons

R. Flume·R. Poghossian·H. Storch
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Abstract

The n-instanton contribution to the Seiberg-Witten prepotential of N=2 supersymmetric d=4 Yang Mills theory is represented as the integral of the exponential of an equivariantly exact form. Integrating out an overall scale and a U(1) angle the integral is rewritten as (4n-3) fold product of a closed two form. This two form is, formally, a representative of the Euler class of the Instanton moduli space viewed as a principal U(1) bundle, because its pullback under bundel projection is the exterior derivative of an angular one-form.

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R. Flume, R. Poghossian, H. Storch. 2001-12-21. The Seiberg-Witten prepotential and the Euler class of the reduced moduli space of instantons. https://doi.org/10.1142/s0217732302006588

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