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Deformations of G2 and Spin(7) Structures

Published online by Cambridge University Press:  20 November 2018

Spiro Karigiannis*
Affiliation:
Department of Mathematics and Statistics, McMaster University, Hamilton, Ontario, email: [email protected]
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Abstract

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We consider some deformations of ${{G}_{2}}$-structures on 7-manifolds. We discover a canonical way to deform a ${{G}_{2}}$-structure by a vector field in which the associated metric gets “twisted” in some way by the vector cross product. We present a system of partial differential equations for an unknown vector field $w$ whose solution would yield a manifold with holonomy ${{G}_{2}}$. Similarly we consider analogous constructions for Spin(7)-structures on 8-manifolds. Some of the results carry over directly, while others do not because of the increased complexity of the Spin(7) case.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 2005

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