The Geometry of Convex Transitive Banach Spaces
نویسندگان
چکیده
Throughout this paper, X will denote a Banach space, S ̄S(X ) and B ̄B(X ) will be the unit sphere and the closed unit ball of X, respectively, and ' ̄'(X ) will stand for the group of all surjective linear isometries on X. Unless explicitly stated otherwise, all Banach spaces will be assumed to be real. Nevertheless, by passing to real structures, the results remain true for complex spaces. Recall that, given u in S, the norm of X is said to be Fre! chet differentiable at u if there exists a continuous linear functional τ(u, [) on X such that
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