Some tits systems with affine Weyl groups in Chevalley groups over Dedekind domains
Some tits systems with affine Weyl groups in Chevalley groups over Dedekind domains
复制标题
Dedekind 域上 Chevalley 群中具有仿射 Weyl 群的一些山雀系统
DOI:
10.1016/0021-8693(88)90272-4
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发表时间:
1988
影响因子:
0.9
通讯作者:
Jun Morita
中科院分区:
文献类型:
--
作者:
E. Abe;Jun Morita
Let A be a Dedekind domain and P be a nonzero prime ideal of A such that P=(p) is principal and the canonical homomorphism A x+(A/P) x of multiplicative groups of units is surjective. Let R be the subring A [;] of the quotient field of A. In this note, we give for a Chevalley group over R a structure of a Tits system with the affine Weyl group and give some applications of such a structure of the groups. Our result contains as special cases the structure of Tits systems with affine Weyl groups in a Chevalley group over a field with a non-trivial discrete valuation due to N. Iwahori and H. Matsumoto [141 and in a Chevalley group over a Laurent polynomial ring due to J. Morita [171. The Chevalley groups over a Laurent polynomial ring are regarded as groups associated with Kac-Moody Lie algebras of affine types, and our proof of the theorem is based on a technique used by D. Peterson and V. Kac [191 for groups associated with Kac-Moody Lie algebras. Since we treat the groups over Dedekind domains not necessarily as fields or local rings, there are some applications of the result. We can obtain a sufficient condition for some Dedekind domains to be universal or quasi-universal, and also we have a sort of Iwasawa decomposition of Chevalley groups over R.