Math Department
Analysis Seminar – Bruno Poggi (University of Minnesota)
ZoomTitle. Additive and scalar-multiplicative Carleson perturbations of elliptic operators on domains with low dimensional boundaries. Abstract. At the beginning of the 90s, Fefferman, Kenig and Pipher (FKP) obtained a rather sharp (additive) perturbation result for the Dirichlet problem of divergence form elliptic operators. Without delving into details, the point is that if the (additive)
Colloquium – John Baldwin (Boston College)
ZoomTitle: Floer homology and the fundamental group Abstract: The most important invariant of a 3-manifold is its fundamental group. One of the most fruitful approaches to understanding the fundamental group is to study its homomorphisms into simpler groups. SU(2) is an especially convenient choice of target because it is one of the simplest non-abelian Lie
Algebra/Topology Seminar – Honghao Gao (Michigan State University)
ZoomTitle: Legendrian invariants, Lagrangian fillings and cluster algebras Abstract: Classifications of Legendrian knots and their exact Lagrangian fillings are central questions in low-dimensional contact and symplectic topology. Recent development suggests that one can use cluster seeds to distinguish exact Lagrangian fillings. It requires a filling-to-cluster functoriality over a moduli space of Legendrian invariants. This invariant
Colloquium – Mariel Vazquez (University of California at Davis)
ZoomDr. Mariel Vazquez Title: Understanding viruses using topological methods Abstract: For the last 25 years I have studied the effects of DNA packaging as well as the action of DNA binding enzymes responsible for important cellular processes such as DNA replication, or transcription of DNA into RNA.
Algebra/Topology Seminar – Dan Rutherford (Ball State University)
ZoomTitle: Normal rulings, augmentations, and the colored HOMFLY-PT polynomial Abstract: Normal rulings are certain decompositions of front diagrams of Legendrian links in $R^3$ that were discovered independently by Chekanov & Pushkar and Fuchs in the context of generating families and augmentations of the Legendrian DG-algebra respectively. They can be used to define combinatorial invariants of
Analysis Seminar – Fernando Lopez-Garcia (Cal State Poly – Pomona)
ZoomTitle: A local-to-global method for inequalities in weighted Sobolev spaces. Abstract: In this talk, we will discuss a certain local-to-global technique with applications to inequalities in weighted Sobolev spaces, such as fractional Poincaré-type inequalities and Korn and conformal Korn inequalities. This technique is based on a certain decomposition of functions that extends the validity of the inequalities
Algebra/Topology Seminar – JungHwan Park (Georgia Institute of Technology)
ZoomTitle: On rationally slice knots Abstract: A knot in the three-sphere is called slice if it bounds a smooth disk in the four-ball. If one only requires the disk to be in a rational homology four-ball, then we say that the knot is rationally slice. We present a rationally slice knot which is not slice even
Analysis Seminar – Alejandro Vélez-Santiago (University of Puerto Rico)
ZoomTitle: The Robin problem over irregular domains Abstract: We will discuss the solvability and global regularity theory for the Laplace equation with Robin boundary conditions over classes of irregular domains which include non-Lipschitz domains and domains with fractal boundaries.
Algebra/Topology Seminar – Marco Trombetti (University of Naples Federico II)
ZoomTitle: Abstract Infinite Group Theory in Linear Groups. Abstract: It is a classical result that the commutator subgroup of a group $G$ is finite whenever such is the factor group $G/Z(G)$. In general, this result cannot be reverted: there are (soluble) groups with a finite commutator subgroup but an infinite factor over the centre. However,
Analysis Seminar – Olli Saari (University of Bonn)
ZoomTitle: On the weak differentiability of the fractional maximal function Abstract: The fractional maximal functions are comparable in Lp size to the Riesz potentials of same order. Its smoothing properties are however more subtle. In this talk, I will discuss Sobolev regularity of fractional maximal functions on the Euclidean n-space as well as on bounded