A noncompact topological minimax theorem
Using the minimax inequality of \textit{Ky Fan} [Inequalities III, Proc. 3rd Symp., Los Angeles 1969, 103-113 (1972; Zbl 0302.49019)], \textit{Ha Chung- Wei} [Pac. J. Math. 97, 115-117 (1981; Zbl 0474.49015)] obtained a noncompact version of Sion's minimax theorem [\textit{M. Sion}, ibid. 8, 171-176 (1958; Zbl 0081.115)] in topological vector spaces. In this note, we extend Ha's theorem to a topological minimax theorem without requiring any linear structure on the underlying spaces.
scientific article; zbMATH DE number 57733