Zobrazeno 1 - 10
of 39
pro vyhledávání: '"Vladimir P. Fonf"'
Publikováno v:
Journal of Mathematical Analysis and Applications. 434:84-92
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::b85859060f1494efadb67212e6f3a46d
https://doi.org/10.1016/j.jmaa.2015.09.002
https://doi.org/10.1016/j.jmaa.2015.09.002
The aim of this note is to present two results that make the task of finding equivalent polyhedral norms on certain Banach spaces, having either a Schauder basis or an uncountable unconditional basis, easier and more transparent. The hypotheses of bo
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::4b0df03df7070e058af12e9893a3d94e
Publikováno v:
Proceedings of the American Mathematical Society. 143:4845-4849
We show that if X X and Y Y are Banach spaces, where Y Y is separable and polyhedral, and if T : X → Y T:X\to Y is a bounded linear operator such that T ∗ ( Y ∗ ) T^*(Y^*) contains a boundary B B of X X , then X X is separable and isomorphic to
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::22b37427adfe0cc25be17bf4768c7bbb
https://doi.org/10.1090/proc/12644
https://doi.org/10.1090/proc/12644
Publikováno v:
Israel Journal of Mathematics. 203:109-140
The Gurariy space G is defined by the property that for every pair of finite dimensional Banach spaces L ⊂ M, every isometry T: L → G admits an extension to an isomorphism \(\mathop T\limits^ \sim :M \to G\) with ‖T‖‖T−1‖ ≤ 1 + ∈. W
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::0273d28281dd2c70a23c73b841c6ec88
https://doi.org/10.1007/s11856-014-0016-4
https://doi.org/10.1007/s11856-014-0016-4
Autor:
Vladimir P. Fonf, Clemente Zanco
Publikováno v:
Canadian Mathematical Bulletin. 57:42-50
We prove that, given any covering of any infinite-dimensional Hilbert space H by countably many closed balls, some point exists in H which belongs to infinitely many balls. We do that by characterizing isomorphically polyhedral separable Banach space
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::b346c1f39ef4f16d6d8d834b68c846e8
https://doi.org/10.4153/cmb-2012-027-7
https://doi.org/10.4153/cmb-2012-027-7
Publikováno v:
Studia Mathematica. 222:157-163
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::c56a9a62fcfbbc4b70062951269b2af0
https://doi.org/10.4064/sm222-2-3
https://doi.org/10.4064/sm222-2-3
Publikováno v:
Journal of Functional Analysis. 266:247-264
The aim of this paper is to present two tools, Theorems 4 and 7, that make the task of finding equivalent polyhedral norms on certain Banach spaces easier and more transparent. The hypotheses of both tools are based on countable decompositions, eithe
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::3c0fb13af44b613d8c6e56d53ee71abe
https://doi.org/10.1016/j.jfa.2013.10.007
https://doi.org/10.1016/j.jfa.2013.10.007
Autor:
S. Dutta, Vladimir P. Fonf
Publikováno v:
The Quarterly Journal of Mathematics. 65:887-891
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::21e13577ced073ff0e784d75b8b24cf2
https://doi.org/10.1093/qmath/hat041
https://doi.org/10.1093/qmath/hat041
Publikováno v:
The Journal of Geometric Analysis. 24:1891-1897
We prove that, given any covering of any separable infinite-dimensional uniformly rotund and uniformly smooth Banach space X by closed balls each of positive radius, some point exists in X which belongs to infinitely many balls.
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::5132fab9a71f1879b9c12a41868a6799
https://doi.org/10.1007/s12220-013-9400-2
https://doi.org/10.1007/s12220-013-9400-2
Publikováno v:
Journal of Approximation Theory. 163:1748-1771
In the present paper, we study conditions under which the metric projection of a polyhedral Banach space X onto a closed subspace is Hausdorff lower or upper semicontinuous. For example, we prove that if X satisfies (*) (a geometric property stronger
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::e1716e3181614b7379744bb4a194bb6e
https://doi.org/10.1016/j.jat.2011.06.011
https://doi.org/10.1016/j.jat.2011.06.011