Normal structure coefficients for Banach spaces
نویسندگان
چکیده
منابع مشابه
On Estimates of Normal Structure Coefficients of Banach Spaces
We obtained the estimates of Normal structure coefficient N(X) by NeumannJordan constant CNJ(X) of a Banach space X and found that X has uniform normal structure if CNJ(X) < (3 + √ 5)/4. These results improved both Prus’ [6] and Kato, Maligranda and Takahashi’s [4] work.
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In this paper, we introduce parameters slε(X) and sl0(X) based on slices of Banach space X . Using these parameters we describe some new properties of Banach spaces related to normal structure, uniformly non-squareness and others. In particular, we prove that if sl 2 3 (X) < 2, then X has normal structure, and sl0(X) = ε0(X) where ε0(X) is the characteristic of convexity of X . In addition, we ...
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ژورنال
عنوان ژورنال: Pacific Journal of Mathematics
سال: 1980
ISSN: 0030-8730,0030-8730
DOI: 10.2140/pjm.1980.86.427