Abstract. The paper continues and completes the study of pure bi-isometries begun in [Po2]. Characterizations for different parts of a double commuting bi-isometry in terms of the Berger-Coburn-Lebow model [BCL] are given. Finally, as consequences, similar results are obtained for dual double commuting bi-isometries.
AMS Subject Classification
(1991): 47A45
Keyword(s):
bi-isometry,
Wold-type decomposition,
double commuting,
bi-shift,
unitary,
completely non-unitary
Received January 2, 2001. (Registered under 2845/2009.)
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