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On the Notion of Relative Property (T) for Inclusions of Von Neumann Algebras

Jesse Peterson·Sorin Popa
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Abstract

We prove that the notion of relative property (T) (or rigidity) for inclusions of finite von Neumann algebras defined in [Po1] is equivalent to a weaker property, in which no ``continuity constants'' are required. The proof is by contradiction and uses infinite products of completely positive maps, regarded as correspondences.

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Jesse Peterson, Sorin Popa. 2004-03-21. On the Notion of Relative Property (T) for Inclusions of Von Neumann Algebras. https://arxiv.org/abs/math/0402417

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