arXiv math/05021142005-02-07math.AGmath.RT

Frobenius splitting of equivariant closures of regular conjugacy classes

Jesper Funch Thomsen

备注：: 23 pages

英文摘要：

Let $G$ denote a connected semisimple and simply connected algebraic group over an algebraically closed field $k$ of positive characteristic and let $g$ denote a regular element of $G$. Let $X$ denote any equivariant embedding of $G$. We prove that the closure of the conjugacy class of $g$ within $X$ is normal and Cohen-Macaulay. Moreover, when $X$ is smooth we prove that this closure is a local complete intersection. As a consequence, the closure of the unipotent variety within $X$ share the same geometric properties.

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