Results 41 to 50 of about 1,382 (80)
An Inequality in Metric Spaces [PDF]
, 2004 In this note we establish a general inequality valid in metric spaces that is related to the polygonal inequality and admits also a natural geometrical interpretation.
Dragomir, Sever S, Goşa, Anca C
core
Boundedness and surjectivity in normed spaces
International Journal of Mathematics and Mathematical Sciences, Volume 32, Issue 3, Page 149-165, 2002., 2002 We define the (w* ‐) boundedness property and the (w* ‐) surjectivity property for sets in normed spaces. We show that these properties are pairwise equivalent in complete normed spaces by characterizing them in terms of a category‐like property called (w* ‐) thickness. We give examples of interesting sets having or not having these properties.
Olav Nygaard
wiley +1 more source
Phillips' Lemma for L-embedded Banach spaces
, 2010 In this note the following version of Phillips' lemma is proved. The L-projection of an L-embedded space - that is of a Banach space which is complemented in its bidual such that the norm between the two complementary subspaces is additive - is weak ...
Pfitzner, Hermann
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A note on nonfragmentability of Banach spaces
International Journal of Mathematics and Mathematical Sciences, Volume 27, Issue 1, Page 39-44, 2001., 2001 We use Kenderov‐Moors characterization of fragmentability to show that if a compact Hausdorff space X with the tree‐completeness property contains a disjoint sequences of clopen sets, then (C(X), weak) is not fragmented by any metric which is stronger than weak topology.
S. Alireza Kamel Mirmostafaee
wiley +1 more source
SPARSE APPROXIMATION AND RECOVERY BY GREEDY ALGORITHMS IN BANACH SPACES
Forum of Mathematics, Sigma, 2014 We study sparse approximation by greedy algorithms. We prove the Lebesgue-type inequalities for the weak Chebyshev greedy algorithm (WCGA), a generalization of the weak orthogonal matching pursuit to the case of a Banach space.
V. N. TEMLYAKOV
doaj +1 more source
A proof of uniqueness of the Gurarii space
, 2011 We present a short and elementary proof of isometric uniqueness of the Gurarii space.Comment: 6 pages, some improvements ...
A. Avilés +9 more
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International Journal of Mathematics and Mathematical Sciences, Volume 27, Issue 10, Page 631-639, 2001., 2001 Given an n‐normed space with n ≥ 2, we offer a simple way to derive an (n − 1)‐norm from the n‐norm and realize that any n‐normed space is an (n − 1)‐normed space. We also show that, in certain cases, the (n − 1)‐norm can be derived from the n‐norm in such a way that the convergence and completeness in the n‐norm is equivalent to those in the derived ...
Hendra Gunawan, M. Mashadi
wiley +1 more source
Uniform G-Convexity for Vector-Valued Lp Spaces [PDF]
, 2009 2000 Mathematics Subject Classification: 46B20.Uniform G-convexity of Banach spaces is a recently introduced natural generalization of uniform convexity and of complex uniform convexity.
Boyko, Nataliia, Kadets, Vladimir
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KKM and KY fan theorems in modular function spaces
Fixed Point Theory and Applications, 2011 In modular function spaces, we introduce Knaster-Kuratowski-Mazurkiewicz mappings (in short KKM-mappings) and prove an analogue to Ky Fan s fixed point theorem. 2010 Mathematics Subject Classification: Primary 46B20, 47H09; Secondary 47H10.
Latif Abdul +2 more
doaj
The Knaster-Tarski theorem versus monotone nonexpansive mappings
, 2018 Let $X$ be a partially ordered set with the property that each family of order intervals of the form $[a,b],[a,\rightarrow )$ with the finite intersection property has a nonempty intersection.
Espínola, Rafael, Wiśnicki, Andrzej
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