대한수학회보 (Bulletin of the Korean Mathematical Society)

  • 제53권6호
  • /
  • Pages.1823-1830
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  • 2016
  • /
  • 1015-8634(pISSN)
  • /
  • 2234-3016(eISSN)
대한수학회 (Korean Mathematical Society)
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RANGE INCLUSION OF TWO SAME TYPE CONCRETE OPERATORS

  • 투고 : 2015.12.07
  • 발행 : 2016.11.30
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초록

Let H and K be two Hilbert spaces, and let A and B be two bounded linear operators from H to K. We are interested in $RangeB^*{\supseteq}RangeA^*$. It is well known that this is equivalent to the inequality $A^*A{\geq}{\varepsilon}B^*B$ for a positive constant ${\varepsilon}$. We study conditions in terms of symbols when A and B are singular integral operators, Hankel operators or Toeplitz operators, etc.

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참고문헌

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