摘要
设 Γ为一非空集 ,( X ,y ·y) 为 Banach 空间. 本文主要结果 如下:(1) U(c0 (Γ, X),p ) 为稳定 的当且仅当 U( X) 是稳定的.(2) 设 Γ为无限集,那么下 列三条等价:(a) (c0 (Γ, X ),p ) 有 λ性质 , (b) (c0 (Γ, X ),p ) 有一致 λ性质,(c)( X,y ·y) 有一致 λ性质 .(3) 设 Γ为 有限集,那么(c0 (Γ, X ),p ) 有 λ性 质(相应地,一致 λ性质) 当且 仅当( X,y ·y) 有 λ性质(相应地,一致 λ性质).(4) (c0 (Γ, X),p ) 有 Kadets 性质 (相应地, Kadets Klee 性质) 当且仅 当( X,y ·y) 有 Kadets 性质(相 应地, Kadets Klee 性质 ).(5) w ∈ S(c0 (Γ, X),p ) 是 U(c0 (Γ, X),p ) 的可凹点(相应 地, P C) 当且仅当对于 任意的 t∈ E(w ),w (t) 是(x ∈ X: yx y ≤ yw (t)y) 的可凹点 (相应地, P C).
Let Γ be a nonempty set and (X,‖·‖) a Banach space. The main results of this paper are as follows: (1) U(c 0(Γ,X),p) is stable if and only if U(X) is stable. (2) If Γ is an infinite set, then the following are equivalent: (a) (c 0(Γ,X),p) has the λ property; (b) (c 0(Γ,X),p) has the uniform λ property; (c) (X,‖·‖) has the uniform λ property. (3) If Γ is a finite set, then (c 0(Γ,X),p) has the λ property (resp. the uniform λ property) if and only if (X, ‖·‖) has the λ property (resp. the uniform λ property). (4) (c 0(Γ,X),p) has the Kadets property (resp. the Kadets Klee property) if and only if (X,‖·‖) has the Kadets property (resp. the Kadets Klee property). (5) A point w∈S(c 0(Γ,X),p) is a denting point (resp. a PC) of U(c 0(Γ,X),p) if and only if for each t∈E(w), w(t) is a denting point (resp. a PC) of (x∈X:‖x‖≤‖w(t)‖).
出处
《数学研究》
CSCD
1999年第2期125-132,共8页
Journal of Mathematical Study
关键词
赋Day范数
BANACH空间
稳定性
有限集
无限集
stable unit ball, uniformly stable unit ball, λ property, uniform λ property, K property, K K property, UKK property, denting point, G space