16:00
Holonomic D-modules, b-functions, and coadmissibility
Abstract
Since differentiation generally lowers exponents, it is straightforward that the space of Laurent polynomials $\mathbb{C}[x, x^{-1}]$ is a finitely generated module over the ring of differential operators $\mathbb{C}[x, \mathrm{d}/\mathrm{d}x]$. This innocent looking fact has been vastly generalized to a statement about holonomic D-modules, using the beautiful theory of b-functions (or Bernstein—Sato polynomials). I will give an overview of the classical theory before discussing some recent developments concerning a $p$-adic analytic analogue, which is joint work with Thomas Bitoun.
16:00
An overview of the SYZ conjecture
Abstract
The Strominger-Yau-Zaslow (SYZ) conjecture postulates that mirror dual Calabi-Yau manifolds carry dual special Lagrangian fibrations. Within the study of Mirror Symmetry the SYZ conjecture has provided a particularly fruitful point of convergence of ideas from Riemannian, Symplectic, Tropical, and Algebraic geometry over the last twenty years. I will attempt to provide a brief overview of this aspect of Mirror Symmetry.
Generalized Polar Geometry
Abstract
Polar classes are very classical objects in Algebraic Geometry. A brief introduction to the subject will be presented and ideas and preliminarily results towards generalisations will be explained. These ideas can be applied towards variety sampling and relevant applications.
12:00
Two-loop amplitudes from the Riemann Sphere
Abstract
Massless Quantum Field Theories can be described perturbatively by chiral worldsheet models - the so-called Ambitwistor Strings. In contrast to conventional string theory, where loop amplitudes are calculated from higher genus Riemann surfaces, loop amplitudes in the ambitwistor string localise on the non-separating boundary of the moduli space. I will describe the resulting framework for QFT amplitudes from (nodal) Riemann spheres, building up from tree-level to two-loop amplitudes.
David Sumpter - Soccermatics: could a Premier League team one day be managed by a mathematician? SOLD OUT
Former Barcelona, Bayern Munich and current Manchester City coach Pep Guardiola is considered by many to be a footballing genius. He has revolutionised the tactical approach to football and that revolution has come about through his careful study of the geometry of the game. But can abstract mathematics really help a team improve its performance?
David Sumpter thinks it can. Unlike the simple statistics applied to (lesser) sports, football is best understood through the patterns the players create together on the field. From the geometry of shooting, through the graph theory of passing, to the tessellations created by players as they find space to move in to, all of these patterns can be captured by mathematical models. As a result, football clubs are increasingly turning to mathematicians.
David Sumpter is Professor of Applied Mathematics at the University of Uppsala, Sweden. His scientific research covers everything from the inner workings of fish schools and ant colonies, the analysis of the passing networks of football teams and segregation in society.
5.00pm-6.00pm, Mathematical Institute, Oxford
Please email @email to register
Watch live:
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The Oxford Mathematics Public Lectures are generously supported by XTX Markets.
16:00
The Story of C^infinity Algebraic Geometry
Abstract
After considering motivations in symplectic geometry, I’ll give a summary of $C^\infty$-Algebraic Geometry and how to extend these concepts to manifolds with corners.
14:15
Tropically constructed Lagrangians in mirror quintic threefolds
Abstract
In this talk, we will explain how to construct embedded closed Lagrangian submanifolds in mirror quintic threefolds using tropical curves and the toric degeneration technique. As an example, we will illustrate the construction for tropical curves that contribute to the Gromov–Witten invariant of the line class of the quintic threefold. The construction will in turn provide many homologous and non-Hamiltonian isotopic Lagrangian
rational homology spheres, and a geometric interpretation of the multiplicity of a tropical curve as the weight of a Lagrangian. This is a joint work with Helge Ruddat.
14:15
Gluing methods for Vortex dynamics in Euler flows
Abstract
We consider the two-dimensional Euler flow for an incompressible fluid confined to a smooth domain. We construct smooth solutions with concentrated vorticities around $k$ points which evolve according to the Hamiltonian system for the Kirkhoff-Routh energy, using an outer-inner solution gluing approach. The asymptotically singular profile around each point resembles a scaled finite mass solution of Liouville's equation.
We also discuss the {\em vortex filament conjecture} for the three-dimensional case. This is joint work with Juan D\'avila, Monica Musso and Juncheng Wei.
14:15
Orientation problems in 7-dimensional gauge theory
Abstract
After discussing a general excision technique for constructing canonical orientations for moduli spaces that derive from an elliptic equation, I shall
explain how to carry out this program in the case of G2-instantons and the 7-dimensional real Dirac operator. In many ways our approach can
be regarded as a categorification of the Atiyah-Singer index theorem. (Based on joint work with Dominic Joyce.)