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arXiv · 2603.04953

Gravitational instantons from closed superstring field theory

Ivo Sachs·Xianghang Zhang
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Abstract

We test exact marginality of the deformation describing the resolution of a $\mathbb{Z}_2$ orbifold by analyzing the closed superstring equations of motion to third order in the size, including $\alpha'$ corrections. We find that the third order correction is unobstructed for all deformation moduli. We are also able to reproduce the Eguchi-Hanson gravitational instanton up to the second order in the field theory limit with a suitable choice of moduli.

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Ivo Sachs, Xianghang Zhang. 2026-03-05. Gravitational instantons from closed superstring field theory. https://arxiv.org/abs/2603.04953

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