Reflection subgroups of finite complex reflection groups
نویسندگان
چکیده
منابع مشابه
On finite index reflection subgroups of discrete reflection groups
Let G be a discrete group generated by reflections in hyperbolic or Euclidean space, and H ⊂ G be a finite index subgroup generated by reflections. Suppose that the fundamental chamber of G is a finite volume polytope with k facets. In this paper, we prove that the fundamental chamber of H has at least k facets. 1. Let X be hyperbolic space H, Euclidean space E or spherical space S . A polytope...
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Let G be a finite group of complex n× n unitary matrices generated by reflections acting on C. Let R be the ring of invariant polynomials, and χ be a multiplicative character of G. Let Ω be the R-module of χ-invariant differential forms. We define a multiplication in Ω and show that under this multiplication Ω has an exterior algebra structure. We also show how to extend the results to vector f...
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ژورنال
عنوان ژورنال: Journal of Algebra
سال: 2012
ISSN: 0021-8693
DOI: 10.1016/j.jalgebra.2012.04.033