Given an Orlicz NN-function φ\varphi and a positive decreasing weight ww, we present criteria for the diameter two property and for the Radon-Nikodým property in the Orlicz-Lorentz function and the sequence spaces Λφ,w\Lambda_{\varphi,w} and λφ,w\lambda_{\varphi,w}. We show that in the spaces Λφ,w\Lambda_{\varphi,w} and λφ,w\lambda_{\varphi,w}, equipped with the Luxemburg norm, the diameter of any relatively weakly open subset of the unit ball in these spaces is two if and only if φ\varphi does not satisfy the appropriate Δ2\Delta_2-condition, while they have the Radon-Nikodým property if and only if φ\varphi satisfies the appropriate Δ2\Delta_2-condition.

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Anna Kamińska

Dept. of Mathematical Sciences, University of Memphis, Memphis, TN 38152-3240, U.S.A.

kaminska@memphis.edu

Hyung-Joon Tag

Dept. of Mathematical Sciences, University of Memphis, Memphis, TN 38152-3240, U.S.A.

htag@memphis.edu
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A. Kamińska, H.-J. Tag. “Diameter of Weak Neighborhoods and the Radon-Nikodým Property in Orlicz-Lorentz Spaces.” Journal of Convex Analysis 24 (2017), No. 3, 969–985. https://doi.org/10.68381/jca24058