In this master’s thesis two recent results related to the problem of the extension of Lipschitz functions are presented.
The first one deals with functions defined on subsets of metric spaces with values in the real numbers that are both Lipschitz and continuous with respect to some given topology on the metric space (not necessarily the topology induced by the metric). A condition is given when such functions admit extensions to the whole space that preserve both the Lipschitz condition and continuity with respect to the topology.
The second one examines the possibility of “continuous” selections of extensions for Lipschitz functions between Hilbert spaces.