In functional analysis and related areas of mathematics a polar topology, topology of -convergence or topology of uniform convergence on the sets of is a method to define locally convex topologies on the vector spaces of a dual pair.
Given a dual pair and a family of sets in such that for all in the polar set is an absorbent subset of , the polar topology on is defined by a family of semi norms . For each in we define
The semi norm is the gauge of the polar set .
A polar topology is sometimes called topology of uniform convergence on the sets of because given a dual pair and a polar topology on defined by the gauges of the polar sets , a sequence in converges to if and only if for all semi norms
Or, to put it differently, for all sets