A new criterion for $k$-hyponormality via weak subnormality
نویسندگان
چکیده
منابع مشابه
Subnormality and 2-hyponormality for Toeplitz Operators
Let H and K be complex Hilbert spaces, let L(H,K) be the set of bounded linear operators from H to K and write L(H) := L(H,H). An operator T ∈ L(H) is said to be normal if T ∗T = TT ∗, hyponormal if T ∗T ≥ TT ∗, and subnormal if T = N |H, where N is normal on some Hilbert space K ⊇ H. If T is subnormal then T is also hyponormal. Recall that the Hilbert space L2(T) has a canonical orthonormal ba...
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ژورنال
عنوان ژورنال: Proceedings of the American Mathematical Society
سال: 2004
ISSN: 0002-9939,1088-6826
DOI: 10.1090/s0002-9939-04-07727-5