arXiv 0806.49222008-06-30math.RA

Automorphisms and derivations of Borel subalgebras and their nilradicals in Kac-Moody algebras

Jun Morita, Kaiming Zhao

发表信息：: Communications in Contemporary Mathematics, Vol.14, No.2(2012), 63-84

英文摘要：

In this paper, we determine derivations of Borel subalgebras and their derived subalgebras called nilradicals, in Kac-Moody algebras (and contragredient Lie algebras) over any field of characteristic 0; and we also determine automorphisms of those subalgebras in symmetrizable Kac-Moody algebras. The results solve a conjecture posed by R. V. Moody about 30 years ago which generalizes a result by B. Kostant and which is discussed by A. Fialowski using Lie algebra cohomology in case of affine type.

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