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Coxeter groups, Lorentzian lattices, and K3 surfaces

Richard E. Borcherds
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Abstract

The main result of this paper describes the normalizer of a finite parabolic subgroup of a (possibly infinite) Coxeter group. We use this to compute the automorphism groups of some Lorentzian lattices and K3 surfaces.

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Richard E. Borcherds. 1998-07-26. Coxeter groups, Lorentzian lattices, and K3 surfaces. https://arxiv.org/abs/math/9806141

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