Trace class perturbations of isometries and unitary dilations

Carey, Richard W.

doi:10.1090/S0002-9939-1974-0358399-5

Trace class perturbations of isometries and unitary dilations
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Proc. Amer. Math. Soc. 45 (1974), 229-234 Request permission

Abstract:

Let $U$ and $V$ be isometries acting on a Hilbert space. If $U - V$ belongs to the trace class we show that the absolutely continuous parts of the corresponding minimal unitary dilations are unitarily equivalent.

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