A type III₁ factor with the smallest outer automorphism group

2023/12/07 by Soham Chakraborty, Chakraborty, Soham
Mathematics · Medicine · #Geometric and Algebraic Topology #Rings, Modules, and Algebras #Chronic Lymphocytic Leukemia Research

paper · pdf · doi:10.48550/arxiv.2312.04702

Abstract

The canonical modular homomorphism provides an embedding of ℝ into the outer automorphism group Out(M) of any type III₁ factor M. We provide an explicit construction of a full factor of type III₁ with separable predual such that the outer automorphism group is minimal, i.e. this embedding is an isomorphism. We obtain such a III₁ factor by using an amalgamated free product construction.

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