On the closedness of the algebraic difference of closed convex sets
نویسندگان
چکیده
We characterize in a reflexive Banach space all the closed convex sets containing no lines for which the condition ensures the closedness of the algebraic difference for all closed convex sets . We also answer a closely related problem: determine all the pairs , of closed convex sets containing no lines such that the algebraic difference of any sufficiently small uniform perturbation of and remains closed. As an application, we state the bradest settting for the strict separation theorem in a reflexive Banach space.
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