Operator algebras, wandering subspaces and wavelet theory /

We show that given a unitary system U that is closed under

Bibliographic Details
Main Author: Kamat, Vishnu Govind, 1965-
Format: Thesis Book
Language:English
Published: [Place of publication not identified] : [publisher not identified] ; 1997.
Subjects:
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Description
Summary:We show that given a unitary system U that is closed under
right multiplication by elements of a group Uo contained in
it, there exists a *-anti-homomorphism K [ ], (that depends
on the wandering vector V)) that maps the von Neumann algebra
w* (Uo) onto IS' (U) ( which is the intersection of the local
commutant of U at 'O and the commutant of the projection Po
on Ep = [UoO] ) such that for each unitary operator U in w*
(Uo), K[ ] (U) is a unitary operator in C,, (U) with the
property that Uo = K [ ], (U),O. This generalizes a result
of Dai and Larson who proved it for the case where Uo is
abelian. We also give a positive solution to an open problem
posed by Dai and Larson. We show that even when Uo is non-
abelian, and 71 is a wandering vector in E[ ] for some fixed
wandering vector O, there exists a unitary operator W E
w*(Uo) such that q = W[ ]. Then it is shown that the theory
of unitary systems and wandering vectors can be generalized
to the more general situation of wandering subspaces. We
show that there is a *-anti-homomorphism from w*(Uo) into the
local commutant of U at a wandering subspace p. In addition
we show that if a unitary group has a wandering subspace of a
certain dimension then it can have wandering subspaces of
only that one dimension. We also show that the standard
wavelet unitary system has wandering subspaces of any
dimension including infinity.
Item Description:Vita.
"Major Subject: Mathematics".
Physical Description:vi, 56 leaves ; 28 cm.
Issued also on microfiche from University Microfilms Inc.
Bibliography:Includes bibliographical references: pages 54-55.