Characterization of weak type by the entropy distribution of r-nuclear operators

• Autorzy: Martin Defant , Marius Junge
• Języki publikacji: EN

Abstrakty

EN

The dual of a Banach space X is of weak type p if and only if the entropy numbers of an r-nuclear operator with values in a Banach space of weak type q belong to the Lorentz sequence space $ℓ_{s,r}$ with 1/s + 1/p + 1/q = 1 + 1/r (0 < r < 1, 1 ≤ p, q ≤ 2). It is enough to test this for Y = X*. This extends results of Carl, König and Kühn.

Słowa kluczowe

EN

entropy numbers; r-nuclear operators; weak type

Kategorie tematyczne

• 47B06: Riesz operators; eigenvalue distributions; approximation numbers, s -numbers, Kolmogorov numbers, entropy numbers, etc. of operators
• 47B20: Subnormal operators, hyponormal operators, etc.

• Wydawca: Institute of Mathematics Polish Academy of Sciences
• Czasopismo: Studia Mathematica
• Rocznik: 1993
• Tom: 107
• Numer: 1
• Strony: 1-14

Daty

wydano

1993

otrzymano

1992-01-07

poprawiono

1993-03-16

Twórcy

autor

Martin Defant

• Mathematisches Seminar, Universität Kiel, Ludewig-Meyn-Str. 4, D-24098 Kiel, Germany

autor

Marius Junge

• Mathematisches Seminar, Universität Kiel, Ludewig-Meyn-Str. 4, D-24098 Kiel, Germany

Bibliografia

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