Characteristic Functions for Ergodic Tuples

Santanu Dey; Rolf Gohm

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Characteristic Functions for Ergodic Tuples

Santanu Dey·Rolf Gohm

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Abstract

Motivated by a result on weak Markov dilations, we define a notion of characteristic function for ergodic and coisometric row contractions with a one-dimensional invariant subspace for the adjoints. This extends a definition given by G. Popescu. We prove that our characteristic function is a complete unitary invariant for such tuples and show how it can be computed.

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BibTeX RIS

Santanu Dey, Rolf Gohm. 2006-12-12. Characteristic Functions for Ergodic Tuples. https://arxiv.org/abs/math/0506560

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