Geometry seminar by Oliviero Malech - REMINDER

[ZUDDAS DANIELE]

This is a reminder for today's Geometry talk by Oliviero Malech (SISSA) at our Department.

Title:  Recepies for exotic 2-links in 4-manifolds.

Abstract: Two smoothly embedded surfaces in the same smooth 4-manifold are called exotic if they are C^0 ambient isotopic without being smoothly isotopic.
In this talk, I will briefly introduce this peculiar phenomenon and I will sketch a construction of Torres to produce infinite families of 2-spheres that are pairwise exotic and topologically unknotted (each 2-sphere bounds a locally flat embedded 3-disk). I will then present a generalization of this construction based on a joint work with V. Bais, Y .Benyahia and R. Torres (see https://arxiv.org/abs/2206.09659). In particular we will produce exotic families of n-component 2-links (disjoint union of n embedded 2-spheres) for which the fundamental group of the complement is free with n generators.
Lastly we will explore some of the proprieties of the constructed exotic families and we will compare them to proprieties of other families arising from different constructions.

When: Wednesday 24 January, 15:00.
Venue: Dipartimento di Matematica Informatica e Geoscienze
Sala Seminario, III floor, via Valerio 12/1.

Everyone is cordially invited.
Daniele Zuddas