In functional analysis, a discipline within mathematics, a locally convex topological vector space (TVS) is said to be infrabarrelled (also spelled infrabarreled) if every bounded barrel is a neighborhood of the origin. If is a Hausdorff locally convex space then the canonical injection from into its bidual is a topological embedding if and only if is infrabarrelled. Every quasi-complete infrabarrelled space is barrelled. Every barrelled space is infrabarrelled. A closed vector subspace of an infrabarrelled space is, however, not necessarily infrabarrelled. Every product and locally convex direct sum of any family of infrabarrelled spaces is infrabarrelled. Every separated quotient of an infrabarrelled space is infrabarrelled.
Ulrich Lemmin, Wolf Hendrik Huwald, Marc Parlange, Ivan Lunati, Nikki Vercauteren