Operators with C * - Algebra Generated by a Unilateral Shift
نویسندگان
چکیده
If T is an operator on a Hubert space %, this paper gives necessary and sufficient conditions on 7" such that C*(T), the C*-algebra generated by T, is generated by a unilateral shift of some multiplicity. This result is then specialized to the cases in which T is a hyponormal or subnormal operator. In particular, it is shown how to prove a recent conjecture of C. R. Putnam as a consequence of our result.
منابع مشابه
Unitary Invariants in Multivariable Operator Theory
The problems considered in this paper come as a natural continuation of our program to develop a free analogue of Sz.-Nagy–Foiaş theory, for row contractions. An n-tuple (T1, . . . , Tn) of operators acting on a Hilbert space is called row contraction if T1T ∗ 1 + · · ·+ TnT ∗ n ≤ I. In this study, the role of the unilateral shift is played by the left creation operators on the full Fock space ...
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