Some theorems on the crossed products of finite factors
نویسندگان
چکیده
منابع مشابه
Duality Theorems for Crossed Products over Rings
In this note we extend duality theorems for crossed products obtained by M. Koppinen and C. Chen from the case of a base field or a Dedekind domain to the case of an arbitrary noetherian commutative ground ring under fairly weak conditions. In particular we extend an improved version of the celebrated Blattner-Montgomery duality theorem to the case of arbitrary noetherian ground rings.
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Let k be a field, R a k-algebra and A = R[θ1, θ2, . . . , θn] a PoincaréBirkhoff-Witt extension of R. If each θi acts locally finitely on R, then we show that GKdim(A) = GKdim(R) + n. From this we deduce some results concerning incomparability, prime length and Tauvel’s height formula in the crossed product R?g where g is a finite-dimensional Lie algebra acting as derivations on R. Similar resu...
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ژورنال
عنوان ژورنال: Tohoku Mathematical Journal
سال: 1962
ISSN: 0040-8735
DOI: 10.2748/tmj/1178244117