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Addendum to "Classification of irreducible holonomies of torsion-free affine connection"

Sergei Merkulov·Lorenz Schwachhöfer
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Abstract

The real form Spin(6,H) in End(R^{32}) of Spin(12,C) in End(C^{32}) is absolutely irreducible and thus satisfies the algebraic identities (40) and (41). Therefore, it also occurs as an exotic holonomy and the associated supermanifold M_g admits a SUSY-invariant polynomial. This real form has been erroneously omitted in our paper. Also, the two real four-dimensional exotic holonomies, whose occurrences were un known at the time of writing, have been shown to exist very recently by R. Bryant.

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Sergei Merkulov, Lorenz Schwachhöfer. 1999-11-01. Addendum to "Classification of irreducible holonomies of torsion-free affine connection". https://arxiv.org/abs/math/9911266

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