The Geometry/Topology seminar is organized this academic year (2017-2018) by Ákos Nagy and Michael Abel

- Monday, March 2, 2020, 3:15pm, Physics 119, Geometry/topology Seminar
*Cable knots are not thin*

Subhankar Dey (University of Buffalo, Mathematics)- Thurston's geometrization conjecture and its subsequent proof for Haken manifolds distinguish knots in S^3 by the geometries in the complement of the knots. While the definition of alternating knots make use of nice knot diagrams, Knot Floer homology, a knot invariant toolbox, defined by Ozsvath-Szabo and Rasumussen, generalizes the definition of alternating knots in the context of knot Floer homology and defines family of quasi-alternating knots which contains all alternating knots. Using Lipshitz-Ozsvath-Thurston's bordered Floer homology, we prove a partial affirmation of a folklore conjecture in knot Floer theory, which bridges these two viewpoints of looking at knots.

- Monday, March 9, 2020, 3:15pm, Physics 119, Geometry/topology Seminar
*Types of lines and Euler Numbers enriched in GW(k)*

Sabrina Pauli (University of Oslo)- Motivated by Morel's degree in A1-homotopy theory which takes values in the Grothendieck-Witt ring of a field k, Kass and Wickelgren define the Euler number of an oriented vector bundle valued in GW(k) to be the sum of local A1-degrees of the zeros of a generic section. Using this definition they get an enriched count of lines on a smooth cubic surface in GW(k). In my talk I will compute several Euler numbers valued in GW(k). In particular, I will count lines on quintic threefolds. In addition, I will give a geometric interpretation of the local contribution of a line on a quintic threefold to the enriched Euler number. When k = R this geometric interpretation agrees with the Segre type defined by Finashin and Kharlamov.

- Monday, March 16, 2020, 3:15pm, Physics 119, Geometry/topology Seminar
*TBA*

Kyle Hayden (Columbia University, Mathematics) - Monday, March 23, 2020, 3:15pm, Physics 119, Triangle Topology Seminar
*TBA*

Yu Pan (MIT, Mathematics)- TBA

- Monday, March 30, 2020, 3:15pm, Physics 119, Geometry/topology Seminar
*Singular fibres of (holomorphic) Lagrangian fibrations*

Justin Sawon (UNC Chapel Hill, Mathematics)- Compact holomorphic Lagrangian fibrations are higher-dimensional analogues of elliptic K3 surfaces. Their generic fibres are abelian varieties and singular fibres occur in complex codimension one. The structure of singular fibres in codimension one was studied by Matsushita (using toric degeneration) and by Hwang-Oguiso (using complex analytic techniques). A great deal more is known for elliptic K3 surfaces, and in this talk we consider what can be generalized to higher-dimensions.

- Monday, April 6, 2020, 3:15pm, Physics 119, Geometry/topology Seminar
*TBA*

John Lind (CSU-Chico) - Monday, April 20, 2020, 3:15pm, 119 Physics, Geometry/topology Seminar
*TBA*

Ao Sun (Massachusetts Institute of Technology)- TBA

Generated at 1:33am Saturday, February 29, 2020 by Mcal. Top * Reload * Login