Displaying similar documents to “Banach spaces which are semi-L-summands in their biduals.”

Infinite-dimensional sets of constant width and their applications.

Angel Rodríguez Palacios (1990)

Extracta Mathematicae

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Sets of constant width appear as a curiosity in the context of finite-dimensional Euclidean spaces. These sets are convex bodies of such an space with the property that the distance between any two distinct parallel supporting hyperplanes is constant. The easiest example of a set of constant width which is not a ball is the so called Reuleaux triangle in the Euclidean plane. This is the intersection of three closed discs of radius r, whose centers are the vertices of an equilateral triangle...

Properly semi-L-embedded complex spaces

Angel Rodríguez Palacios (1993)

Studia Mathematica

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We prove the existence of complex Banach spaces X such that every element F in the bidual X** of X has a unique best approximation π(F) in X, the equality ∥F∥ = ∥π (F)∥ + ∥F - π (F)∥ holds for all F in X**, but the mapping π is not linear.