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arXiv · 2007.02497

Deformation theory of nearly $\mathrm{G}_2$ manifolds

Shubham Dwivedi·Ragini Singhal
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Abstract

We study the deformation theory of nearly $\mathrm{G}_2$ manifolds. These are seven dimensional manifolds admitting real Killing spinors. We show that the infinitesimal deformations of nearly $\mathrm{G}_2$ structures are obstructed in general. Explicitly, we prove that the infinitesimal deformations of the homogeneous nearly $\mathrm{G}_2$ structure on the Aloff--Wallach space are all obstructed to second order. We also completely describe the cohomology of nearly $\mathrm{G}_2$ manifolds.

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BibTeXRIS

Shubham Dwivedi, Ragini Singhal. 2020-07-06. Deformation theory of nearly $\mathrm{G}_2$ manifolds. https://doi.org/10.4310/cag.2023.v31.n3.a5

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