Analytic model of doubly commuting contractions
نویسندگان
چکیده
منابع مشابه
A Nagy-Foias model for commuting pairs of contractions
The starting point for the Nagy-Foias model for a contractive operator T on Hilbert space is Sz.-Nagy’s observation that T has a canonical minimal unitary dilation to a larger Hilbert space. For a pair T = (T1, T2) of commuting contractions, Ando’s theorem asserts that there exist commuting unitary dilations of T to larger Hilbert spaces, and one might aspire to extend the Nagy-Foias model to s...
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Let S be a subset of a normed space X = (X ,‖ · ‖) and T and I self-mappings of X . Then T is called (1) nonexpansive on S if ‖Tx− Ty‖ ≤ ‖x− y‖ for all x, y ∈ S; (2) Inonexpansive on S if ‖Tx − Ty‖ ≤ ‖Ix − I y‖ for all x, y ∈ S; (3) I-contraction on S if there exists k ∈ [0,1) such that ‖Tx − Ty‖ ≤ k‖Ix − I y‖ for all x, y ∈ S. The set of fixed points of T (resp., I) is denoted by F(T) (resp., ...
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ژورنال
عنوان ژورنال: Operators and Matrices
سال: 2017
ISSN: 1846-3886
DOI: 10.7153/oam-11-07