Morphisms in Low Dimensions

Watanabe's work on embedding calculus has shown us how diffeomorphisms of the 4-sphere may be studied, and Zemke's work has used the functoriality of Floer homology to derive powerful new obstructions to ribbon concordance. A common theme in these works is the emphasis on functoriality of the invariants, rather than simply computation, and a renewed interest in understanding diffeomorphism groups of a manifold rather than single isotopy groups. In this workshop, we propose to bring together experts on these interrelated topics with the aim of improving community understanding of recent developments in low-dimensional topology and promote new advances in the study of global properties of 4-manifolds.