Fri, 18 Oct 2019

16:00 - 17:00
L1

Geometry as a key to the virosphere: Mathematics as a driver of discovery in virology and anti-viral therapy

Reidun Twarock
(University of York)
Further Information

The Oxford Mathematics Colloquia are generously sponsored by Oxford University Press.

Abstract

Viruses encapsulate their genetic material into protein containers that act akin to molecular Trojan horses, protecting viral genomes between rounds of infection and facilitating their release into the host cell environment. In the majority of viruses, including major human pathogens, these containers have icosahedral symmetry. Mathematical techniques from group, graph and tiling theory can therefore be used to better understand how viruses form, evolve and infect their hosts, and point the way to novel antiviral solutions.

In this talk, I will present an overarching theory of virus architecture, that contains the seminal Caspar Klug theory as a special case and solves long-standing open problems in structural virology. Combining insights into virus structure with a range of different mathematical modelling techniques, such as Gillespie algorithms, I will show how viral life cycles can be better understood through the lens of viral geometry. In particular, I will discuss a recent model for genome release from the viral capsid. I will also demonstrate the instrumental role of the Hamiltonian path concept in the discovery of a virus assembly mechanism that occurs in many human pathogens, such as Picornaviruses – a family that includes the common cold virus– and Hepatitis B and C virus. I will use multi-scale models of a viral infection and implicit fitness landscapes in order to demonstrate that therapeutic interventions directed against this mechanism have advantages over conventional forms of anti-viral therapy. The talk will finish with a discussion of how the new mathematical and mechanistic insights can be exploited in bio-nanotechnology for applications in vaccination and gene therapy.

Thu, 10 May 2018

16:00 - 17:00
L6

On spectra of Diophantine approximation exponents

Antoine Marnat
(University of York)
Abstract

Exponents of Diophantine approximation are defined to study specific sets of real numbers for which Dirichlet's pigeonhole principle can be improved. Khintchine stated a transference principle between the two exponents in the cases  of simultaneous approximation and approximation by linear forms. This shows that exponents of Diophantine approximation are related, and these relations can be studied via so called spectra. In this talk, we provide an optimal bound for the ratio between ordinary and uniform exponents of Diophantine approximation for both simultaneous approximation and approximation by linear forms. This is joint work with Nikolay Moshchevitin.

Mon, 11 Jun 2018

14:15 - 15:15
L3

Gradient estimates and applications to nonlinear filtering

CHRISTIAN LITTERER
(University of York)
Abstract

We present sharp gradient estimates for the solution of the filtering equation and report on its applications in a high order cubature method for the nonlinear filtering problem.

Tue, 05 Jun 2018

12:00 - 13:15
L4

A Cohomological Perspective on Algebraic Quantum Field Theory

Eli Hawkins
(University of York)
Abstract

After outlining the principles of Algebraic Quantum Field Theory (AQFT) I will describe the generalization of Hochschild cohomology that is relevant to describing deformations in AQFT. An interaction is described by a cohomology class.

Tue, 24 Oct 2017

12:00 - 13:15
L4

Convergence and new perspectives in perturbative algebraic quantum field theory

Kasia Rejzner
(University of York)
Abstract

In this talk I will present recent results obtained within the
framework of perturbative algebraic quantum field theory. This novel
approach to mathematical foundations of quantum field theory allows to
combine the axiomatic framework of algebraic QFT by Haag and Kastler with
perturbative methods. Recently also non-perturbative results have been
obtained within this approach. I will report on these results and present
new perspectives that they open for better understanding of foundations of
QFT.

Thu, 25 Feb 2016

16:00 - 17:00
L2

Badly approximable points

Victor Beresnevich
(University of York)
Abstract

I will discuss the notion of badly approximable points and recent progress and problems in this area, including Schmidt's conjecture, badly approximable points on manifolds and real numbers badly approximable by algebraic numbers.

Mon, 23 Nov 2015

15:45 - 16:45
Oxford-Man Institute

Rough paths on manifolds revisited

CHRISTIAN LITTERER
(University of York)
Abstract


Abstract: We consider different notions of rough paths on manifolds and study some of the relations between these definitions. Furthermore, we explore extensions to manifolds modelled along infinite dimensional Banach spaces.

Thu, 28 May 2015

16:00 - 17:00
L5

Cubic hypersurfaces over global fields

Pankaj Vishe
(University of York)
Abstract

 Let $X$ be a smooth cubic hypersurface of dimension $m$ defined over a global field $K$. A conjecture of Colliot-Thelene(02) states that $X$ satisfies the Hasse Principle and Weak approximation as long as $m\geq 3$. We use a global version of Hardy-Littlewood circle method along with the theory of global $L$-functions to establish this for $m\geq 6$, in the case $K=\mathbb{F}_q(t)$, where $\text{char}(\mathbb{F}_{q})> 3$.

Mon, 19 Nov 2012

15:45 - 16:45
Oxford-Man Institute

Strong and weak solutions to stochastic Landau-Lifshitz equations

Zdzislaw Brzezniak
(University of York)
Abstract

I will speak about the of weak (and the existence and uniqueness of strong solutions) to the stochastic
Landau-Lifshitz equations for multi (one)-dimensional spatial domains. I will also describe the corresponding Large Deviations principle and it's applications to a ferromagnetic wire. The talk is based on a joint works with B. Goldys and T. Jegaraj.

Tue, 13 Sep 2011
12:00

Secret symmetries of AdS/CFT

Allessandro Torielli
(University of York)
Abstract

We review the representation theory of the integrable model underlying the AdS_5/CFT_4 correspondence. We will discuss short and long multiplets, and their impact on the issue of the universal R-matrix. We will give special emphasis to the role of the so-called 'secret symmetry', which completes the Yangian symmetry of the system to a yet to be understood new type of quantum group.

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