4-dimensional topology offers a unique array of open problems in low dimensional topology. Several of these problems have been solved in higher and lower dimensions, by methods ranging through a wide range of topics. Indeed, in dimension 3, spectacular results have been obtained by successfully harnessing the bridge between topology and geometry, while in dimensions greater than 4, surgery theory provides a toolkit for understanding the classification of manifolds.

Another attractive feature of 4-dimensional topology lies in its connections with other fields. For instance, work in topological category often relies more heavily on methods coming from algebra, while results in the smooth category frequently involve gauge theory and symplectic geometry. On the other hand, the burgeoning study of trisections buildson analogies with 3-dimensional Heegaard splittings, while also drawing on tools from symplectic and contact geometry.

For these reasons, this workshop will assemble both experts in 4-dimensional topology as well as manifold topologists from neighboring fields. Through talks on a variety of topics as well as discussion sessions, the goal is to pool the knowledge from all of these areas in order to stimulate progress on some of the outstanding problems in 4-dimensional topology, as well as to shape future directions of research in this area.