Journal of the Korean Mathematical Society (대한수학회지)
- Volume 32 Issue 2
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- Pages.183-193
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- 1995
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- 0304-9914(pISSN)
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- 2234-3008(eISSN)
A characterization of crossed products without cohomology
- Hong, Jeong-Hee (Department of Applied Mathematics Korea Maritime University)
- Published : 1995.05.01
Abstract
Let N be a $II_1$ factor and G be a finite group acting outerly on N. Then the crossed product algebra $M = N \rtimes G$ is also a $II_1$ factor and $N' \cap M = CI$, i.e. N is irreducible in M. Moreover, N is regular in M, in other words, M is generated by the normalizer $N_M (N)$.
Keywords
- subfactor;
- Jones index;
- depth 2 subfactor;
- group action;
- crossed product algebra;
- fixed point algebra.