Abstract: Given a nonholonomic vector distribution on a smooth manifold M, it is well-known that embedding of the horizontal loop space into the whole loop space is a homotopy equivalence. We know however that horizontal loop spaces have deep singularities and extremely rich local and global structure even if M is contractible. In principle, one can recover hidden structural complexity of the horizontal loop spaces by calculating homology of some natural filtrations of the space. I am going to show two examples of such calculations.
Abstract: One might ask if global surfaces of section (GSS) for Reeb flows in dimension 3 are abundant in two different senses. One might ask if GSS are abundant for a given Reeb flow, or if Reeb flows carrying some GSS are abundant in the set of all Reeb flows. In this talk, answers to these two questions in specific contexts will be presented. First, I would like to discuss a result, obtained in collaboration with Florio, stating that there are explicit sets of Reeb flows on which are right-handed in the sense of Ghys; in particular, for such a flow all finite (non-empty) collections of periodic orbits span a GSS. Then, I would like to discuss genericity results, obtained in collaboration with Colin, Dehornoy and Rechtman, for Reeb flows carrying a GSS; as a particular case of such results, we prove that a C^\infty-generic Reeb flow on an arbitrary closed 3-manifold carries a (rational) GSS.
Abstract: In this talk we will prove that every plane passing through the origin divides an embedded compact free boundary minimal surface of the euclidean 3-ball in exactly two connected surfaces. This result gives evidence to a conjecture by Fraser and Li. This is a joint work with Vanderson Lima from UFRGS, Brazil.
Abstract: (joint work with Jason Lotay) Richard Thomas and Shing-Tung-Yau proposed two conjectures on the existence of special Lagrangian submanifolds and on the use of Lagrangian mean curvature flow to find them. In this talk, I will report on joint work with Jason Lotay to prove these on certain symmetric hyperKahler 4-manifolds. If time permits I may also comment on our work in progress to tackle more refined conjectures of Dominic Joyce regarding the existence of Bridgeland stability conditions on Fukaya categories and their interplay with Lagrangian mean curvature flow.
Abstract: Lipschitz geometry of singular sets is an intensively developing subject which started in 1969 with the work of Pham and Teissier on the Lipschitz classification of germs of plane complex algebraic curves. The purpose of the lecture is to discuss the fundamentals of this geometry in the space of matrices and show how it relates to recent results of singularity theory.
Abstract: Below we consider the evolutes of plane real-algebraic curves and discuss some of their complex and real-algebraic properties. In particular, for a given degree d ≥ 2, we provide lower bounds for the following four numerical invariants: 1) the maximal number of times a real line can intersect the evolute of a real-algebraic curve of degree d; 2) the maximal number of real cusps which can occur on the evolute of a real-algebraic curve of degree d; 3) the maximal number of (cru)nodes which can occur on the dual curve to the evolute of a real-algebraic curve of degree d; 4) the maximal number of (cru)nodes which can occur on the evolute of a real-algebraic curve of degree d.