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arXiv · 1708.07496

Non-classification of free Araki-Woods factors and $\tau$-invariants

Román Sasyk·Asger Törnquist·Stefaan Vaes
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Abstract

We define the standard Borel space of free Araki-Woods factors and prove that their isomorphism relation is not classifiable by countable structures. We also prove that equality of $\tau$-topologies, arising as invariants of type III factors, as well as coycle and outer conjugacy of actions of abelian groups on free product factors are not classifiable by countable structures.

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Román Sasyk, Asger Törnquist, Stefaan Vaes. 2017-08-24. Non-classification of free Araki-Woods factors and $\tau$-invariants. https://doi.org/10.4171/ggd%2F520

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