Abstract
We study Lorentz spaces Γ p,w , where 0<p<∞, andw is a nonnegative measurable weight function. We first present some results concerning new formulas for the quasi-norm, duality, embeddings and Boyd indices. We then show that, whenever Γ p,w does not coincide withL 1+L ∞, it contains an order isomorphic and complemented copy of ℓp. We apply this result to determine criteria for order convexity and concavity as well as for lower and upper estimates. Finally, we characterize the type and cotype of Γ p,w .
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Research partially supported by a grant from the Swedish Natural Science Research Council (Ö-AH/KG 08685-314).
Research supported by a grant from the Swedish Natural Science Research Council (M5105-20005228/2000).
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Kamińska, A., Maligranda, L. On Lorentz spaces Γ p,w . Isr. J. Math. 140, 285–318 (2004). https://doi.org/10.1007/BF02786637
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DOI: https://doi.org/10.1007/BF02786637