Crossed Product

In mathematics, and more specifically in the theory of von Neumann algebras, a crossed product is a basic method of constructing a new von Neumann algebra from a von Neumann algebra acted on by a group. It is related to the semidirect product construction for groups. (Roughly speaking, crossed product is the expected structure for a group ring of a semidirect product group. Therefore crossed products have a ring theory aspect also. This article concentrates on an important case, where they appear in functional analysis.)

Read more about Crossed ProductMotivation, Construction, Properties, Duality, Examples

Other articles related to "products, product, crossed product":

Semidirect Product - Generalizations
... The construction of semidirect products can be pushed much further ... The Zappa–Szep product of groups is a generalization which, in its internal version, does not assume that either subgroup is normal ... There is also a construction in ring theory, the crossed product of rings ...
Crossed Product - Examples
... algebra A to be the complex numbers C, then the crossed product is called the von Neumann group algebra of G ...

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