Free products of von Neumann algebras
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 by Wai Mee Ching PDF
 Trans. Amer. Math. Soc. 178 (1973), 147163 Request permission
Abstract:
A new method of constructing factors of type ${\text {II}_1}$, called free product, is introduced. It is a generalization of the group construction of factors of type ${\text {II}_1}$ when the given group is a free product of two groups. If ${A_1}$ and ${A_2}$ are two von Neumann algebras with separating cyclic trace vectors and orthounitary bases, then the free product ${A_1} \ast {A_2}$ of ${A_1}$ and ${A_2}$ is a factor of type ${\text {II}_1}$ without property $\Gamma$.References

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Additional Information
 © Copyright 1973 American Mathematical Society
 Journal: Trans. Amer. Math. Soc. 178 (1973), 147163
 MSC: Primary 46L10
 DOI: https://doi.org/10.1090/S00029947197303264053
 MathSciNet review: 0326405