Complex Reflection Subgroups of Real Reflection Groups
نویسندگان
چکیده
منابع مشابه
Reflection subgroups of Coxeter groups
We use geometry of Davis complex of a Coxeter group to investigate finite index reflection subgroups of Coxeter groups. The main result is the following: if G is an infinite indecomposable Coxeter group and H ⊂ G is a finite index reflection subgroup then the rank of H is not less than the rank of G. This generalizes results of [7]. We also describe some properties of the nerves of the group an...
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I. MARIN AND J. MICHEL Abstract. Let G ⊂ GL(Cr) be an irreducible finite complex reflection group. We show that (apart from the exception G = S6) any automorphism of G is the product of an automorphism induced by tensoring by a linear character, of an automorphism induced by an element of NGL(Cr)(G) and of what we call a “Galois” automorphism: we show that Gal(K/Q), where K is the field of defi...
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ژورنال
عنوان ژورنال: Journal of Algebra
سال: 2000
ISSN: 0021-8693
DOI: 10.1006/jabr.2000.8404