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Talk:Maschke's theorem

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needed content

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We need a matrix form of Maschke's theorem as well, but I have difficulties creating a good layout for the matrix. Arcfrk 02:54, 7 May 2007 (UTC)[reply]

Generalizations of Maschke's theorem

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It may be interesting to add generalizations of the result. For example, there is a generalized Maschke theorem for crossed products of algebras with finite dimensional semisimple Hopf algebras; see Chapter 7 of "Hopf algebras and their actions on rings", S. Montgomery (1993). Jose Brox (talk) 22:45, 18 September 2023 (UTC)[reply]

Restriction to finite-dimensional representations

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It is stated: "Maschke's theorem addresses the question: when is a general (finite-dimensional) representation built from irreducible subrepresentations using the direct sum operation?"

Why is the finite dimension condition added there? If I'm not mistaken, Maschke's theorem works as well for infinite-dimensional representations (since the group algebra is semisimple). Jose Brox (talk) 23:55, 27 September 2023 (UTC)[reply]