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arXiv · 1303.0963

G-complete reducibility in non-connected groups

Michael Bate·Sebastian Herpel·Benjamin Martin·Gerhard Roehrle
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Abstract

In this paper we present an algorithm for determining whether a subgroup H of a non-connected reductive group G is G-completely reducible. The algorithm consists of a series of reductions; at each step, we perform operations involving connected groups, such as checking whether a certain subgroup of G^0 is G^0 -cr. This essentially reduces the problem of determining G-complete reducibility to the connected case.

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Michael Bate, Sebastian Herpel, Benjamin Martin, Gerhard Roehrle. 2013-03-05. G-complete reducibility in non-connected groups. https://arxiv.org/abs/1303.0963

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