Instanton counting on blowup. II. $K$-theoretic partition function

Hiraku Nakajima; Kota Yoshioka

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Instanton counting on blowup. II. $K$-theoretic partition function

Hiraku Nakajima·Kota Yoshioka

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Abstract

We study Nekrasov's deformed partition function of 5-dimensional supersymmetric Yang-Mills theory compactified on a circle. Mathematically it is the generating function of the characters of the coordinate rings of the moduli spaces of instantons on $\mathbb R^4$. We show that it satisfies a system of functional equations, called blowup equations, whose solution is unique. As applications, we prove (a) logarithm of the partition function times $ε_1ε_2$ is regular at $ε_1 = ε_2 = 0$, (a part of Nekrasov's conjecture), and (b) the genus 1 parts, which are first several Taylor coefficients of the logarithm of the partition function, are written explicitly in terms of the Seiberg-Witten curves in rank 2 case.

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BibTeX RIS

Hiraku Nakajima, Kota Yoshioka. 2005-05-25. Instanton counting on blowup. II. $K$-theoretic partition function. https://arxiv.org/abs/math/0505553

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