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Minimal convergence on Lp spaces

Published online by Cambridge University Press:  19 September 2008

I. Assani
Affiliation:
Department of Mathematics, University of Toronto, Ontario, Canada, M5S 1A1
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Abstract

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Let (X, F, μ) be a probability measure space, p and β real numbers such that 1≤p<+∞ and 0<β<p. For any linear positive operator T satisfying T1, T*1 = 1 we prove the norm and pointwise convergence of the sequence We get then the pointwise and norm convergence in Lp, 0 < β ≥ 1 < p < 2, of the sequence sgn Sif for any positive linear operator on Lp(Ω, A, μ) (μ-σ-finite) verifying ∥(1 − α)I + αSp ≤ 1 for a real number 0 < α < 1. In the particular case α = 1, (S is a contraction), β = p−l, this result gives the pointwise and norm convergence of the sequences introduced by Beauzamy and Enflo in 1985 to the asymptotic center of the sequence .

Type
Research Article
Copyright
Copyright © Cambridge University Press 1990

References

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