Properties of fixed-point sets of nonexpansive mappings in Banach spaces
Properties of fixed-point sets of nonexpansive mappings in Banach spaces
Let <italic>C</italic> be a closed convex subset of the Banach space <italic>X</italic>. A subset <italic>F</italic> of <italic>C</italic> is called a nonexpansive retract of <italic>C</italic> if either <inline-formula content-type="math/mathml"> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="upper F equals normal empty-set"> <mml:semantics> <mml:mrow> <mml:mi>F</mml:mi> <mml:mo>=</mml:mo> <mml:mi mathvariant="normal">∅<!-- ∅ --></mml:mi> </mml:mrow> <mml:annotation encoding="application/x-tex">F = \emptyset</mml:annotation> </mml:semantics> </mml:math> …