Talk:Unitarian trick
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[edit] Opening sentence
"the unitarian trick (occasionally unitarian trick)" looks like a repetition to me. maybe "Weyl's unitarian trick" was intended to be in parenthesis?
- since Unitary trick redirects here, I think it was intended to be the alternative. I've edited accordingly. Hv 02:17, 15 April 2007 (UTC)
[edit] Weyl's theorem
The page on semisimple Lie algebras states
*is semisimple if and only if every representation is completely reducible, that is for every invariant subspace of the representation there is an invariant complement (Weyl's theorem).
directing here. It's hard to find a clear definition of Weyl's theorem here on the "unitarian trick"-page, and I'm not able to derive it from what's here. Does anyone perhaps have a better reference that we could cite? Especially good would be one where the theorem is explicitly stated. 192.38.109.188 16:32, 28 August 2007 (UTC)
is semisimple if and only if every representation is completely reducible,
that is for every invariant subspace of the representation there is an invariant complement (Weyl's theorem).

