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Continuity of the spectrum on a class A(k)

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Let T be a bounded linear operator on a complex Hilbertspace H . An operator T is called class A operator if |T2| ≥ |T|2and is called class A(k) operator if (T*|T|2kT)1/k+1 ≥ |T|2 for a pos-itive number k. In this paper, we show that σ is continuous whenrestricted to the set of class A(k) operators.

Abstract

Let T be a bounded linear operator on a complex Hilbertspace H . An operator T is called class A operator if |T2| ≥ |T|2and is called class A(k) operator if (T*|T|2kT)1/k+1 ≥ |T|2 for a pos-itive number k. In this paper, we show that σ is continuous whenrestricted to the set of class A(k) operators.

참고문헌 (16)

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