The unit ball of P(2l22)

被引:52
作者
Choi, YS [1 ]
Kim, SG [1 ]
机构
[1] Pohang Univ Sci & Technol, Dept Math, Pohang, South Korea
关键词
Hilbert Space; Extreme Point; Unit Ball; Explicit Formula; Unit Sphere;
D O I
10.1007/s000130050292
中图分类号
O1 [数学];
学科分类号
0701 ; 070101 ;
摘要
We classify extreme points and smooth points of the unit ball of the space P((2)l(2)(2)) Of all 2-homogeneous polynomials on the 2-dimensional real Hilbert space l(2)(2) and show that the unit sphere of P((2)l(2)(2)) is the disjoint union of the set of extreme points of its unit ball and the set of smooth ones We also obtain explicit formulas for the norm of f epsilon P((2)l(p)(2))*(p = 1, 2, infinity).
引用
收藏
页码:472 / 480
页数:9
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