predual
A predual of a Banach space is a Banach space X such that the given space Y is (isometrically) the continuous dual of X, that is, Y ≅ X*. The space X is then said to be a predual of Y. Equivalently, Y carries the weak-* topology with respect to X.
Existence and uniqueness: Not every Banach space is a dual space, so not every Y has a
Examples: A basic example is L1, whose dual is L∞, so L1 is a predual of L∞
Relevance: The concept links to topologies and duality in analysis. The weak-* topology on a dual space