대한수학회지 (Journal of the Korean Mathematical Society)

  • 제43권4호
  • /
  • Pages.899-909
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  • 2006
  • /
  • 0304-9914(pISSN)
  • /
  • 2234-3008(eISSN)
대한수학회 (Korean Mathematical Society)
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ON WEYL'S THEOREM FOR QUASI-CLASS A OPERATORS

  • Duggal Bhagwati P. (8 Redwood Grove Northfields Avenue) ;
  • Jeon, In-Ho (Department of Mathematics Education Seoul National University of Education) ;
  • Kim, In-Hyoun (Department of Mathematics Seoul National University)
  • 발행 : 2006.07.01
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초록

Let T be a bounded linear operator on a complex infinite dimensional Hilbert space $\scr{H}$. We say that T is a quasi-class A operator if $T^*\|T^2\|T{\geq}T^*\|T\|^2T$. In this paper we prove that if T is a quasi-class A operator and f is a function analytic on a neigh-borhood or the spectrum or T, then f(T) satisfies Weyl's theorem and f($T^*$) satisfies a-Weyl's theorem.

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참고문헌

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피인용 문헌

  1. Weyl Type Theorems for Left and Right Polaroid Operators vol.66, pp.1, 2010, https://doi.org/10.1007/s00020-009-1738-2
  2. Browder-type Theorems and SVEP vol.8, pp.3, 2011, https://doi.org/10.1007/s00009-010-0085-5
  3. WEYL'S THEOREM FOR CLASS A(k) OPERATORS vol.50, pp.01, 2008, https://doi.org/10.1017/S0017089507003904
  4. A Unifying Approach to Weyl Type Theorems for Banach Space Operators vol.77, pp.3, 2013, https://doi.org/10.1007/s00020-013-2097-6