All Upcoming Events

On Tuesday at 11:30 in TBC, a seminar in the Cosmology series:
Ludovic Van Waerbeke (University of British Columbia)
TBC
On Tuesday at 12:00 in L4, a seminar in the Quantum Field Theory series:
Christian Saemann (Heriot Watt University)
Towards an M5-brane model: A 6d superconformal field theory
Further information: I will discuss a classical six-dimensional superconformal field theory containing a non-abelian tensor multiplet which we recently constructed in arXiv:1712.06623. This theory satisfies many of the properties of the mysterious (2,0)-theory: non-abelian 2-form potentials, ADE-type gauge structure, reduction to Yang-Mills theory and reduction to M2-brane models. There are still some crucial differences to the (2,0)-theory, but our action seems to be a key stepping stone towards a potential classical formulation of the (2,0)-theory. I will review in detail the underlying mathematics of categorified gauge algebras and categorified connections, which make our constructions possible.
On Tuesday at 15:45 in L4, a seminar in the Algebraic Geometry series:
Navid Nabijou (Imperial College London)
A Recursive Formula for Log Gromov-Witten Invariants
Further information: Given a smooth variety X containing a smooth divisor Y, the relative Gromov-Witten invariants of (X,Y) are defined as certain counts of algebraic curves in X with specified orders of tangency to Y. Their intrinsic interest aside, they are an important part of any Gromov-Witten theorist’s toolkit, thanks to their role in the celebrated “degeneration formula.” In recent years these invariants have been significantly generalised, using techniques in logarithmic geometry. The resulting “log Gromov-Witten invariants” are defined for a large class of targets, and in particular give a rigorous definition of relative invariants for (X,D) where D is a normal crossings divisor. Besides being more general, these numbers are  intimately related to constructions in Mirror Symmetry, via the Gross-Siebert program. In this talk, we will describe a recursive formula for computing the invariants of (X,D) in genus zero. The result relies on a comparison theorem which expresses the log Gromov-Witten invariants as classical (i.e. non log-geometric) objects.
On Thursday at 12:45 in L6, a seminar in the Strings Junior series:
Sebastjan Cizels
On Thursday at 16:00 in L6, a seminar in the Number Theory series:
Edgar Assing (University of Bristol)
Voronoi summation and applications to subconvexity
Further information: We will briefly revisit Voronoi summation in its classical form and mention some of its many applications in number theory. We will then show how to use the global Whittaker model to create Voronoi type formulae. This new approach allows for a wide range of weights and twists. In the end we give some applications to the subconvexity problem of degree two $L$-functions.
On Thursday at 16:15 in Beecroft Seminar Room, a seminar in the Theoretical Particle Physics series:
Ian Low (Northwestern University Boston/Argonne National Laboratory)
Nambu-Goldstone bosons: from composite Higgs to scattering amplitudes
On Friday at 14:00 in Dennis Sciama Lecture Theatre, a seminar in the Theoretical Physics Colloquia series:
Tim Hollowood (Swansea)
Unravelling the quantum to classical transition
On Friday at 15:30 in Martin Wood Lecture Theatre, a seminar in the Colloquia Series Seminars series:
To be announced (To be announced)
To be announced
On Monday at 12:45 in L3, a seminar in the String Theory series:
Michael Green (Cambridge and QMUL)
Modular properties of supersttring scattering amplitudes,
Further information: The coefficients of the low energy expansion of closed string amplitudes transform as automorphic functions under En(Z) U-duality groups.  The seminar will give an overview of some features of the coefficients of low order terms in this expansion, which involve a fascinating interplay between multiple zeta values and certain elliptic and hyperelliptic generalisations, Langlands Eisenstein series for the En groups, and the ultraviolet behaviour of maximally supersymmetric supergravity.
On Monday at 14:00 in Dennis Sciama Lecture Theatre, a seminar in the Astrophysics Colloquia series:
NO Colloquium: Bank Holiday
On Monday at 14:15 in L4, a seminar in the Geometry and Analysis series:
Marco Gualtieri (Toronto)
The generalized Kahler potential
Further information: I will explain our recent description of the fundamental degrees of freedom underlying a generalized Kahler structure. For a usual Kahler structure, it is well-known that the geometry is determined by a complex structure, a Kahler class, and the choice of a positive(1,1)-form in this class, which depends locally on only a single real-valued function: the Kahler potential. Such a description for generalized Kahler geometry has been sought since it was discovered in1984. We show that a generalized Kahler structure of symplectic type is determined by a pair of holomorphic Poisson manifolds, a holomorphic symplectic Morita equivalence between them, and the choice of a positive Lagrangian brane bisection, which depends locally on only a single real-valued function, which we call the generalized Kahler potential. To solve the problem we make use of, and generalize, two main tools: the first is the notion of symplectic Morita equivalence, developed by Weinstein and Xu to study Poisson manifolds; the second is Donaldson's interpretation of a Kahler metric as a real Lagrangian submanifold in a deformation of the holomorphic cotangent bundle.
On Monday at 16:15 in Beecroft Seminar Room, a seminar in the Theoretical Particle Physics series:
Fabrizio Caola (IPPP, Durham)
Precision as a path to discovery
On Tuesday, May 29, at 15:45 in L4, a seminar in the Algebraic Geometry series:
Milena Hering (Edinburgh)
Frobenius splittings of toric varieties
Further information: Varieties admitting Frobenius splittings exhibit very nice properties. For example, many nice properties of toric varieties can be deduced from the fact that they are Frobenius split. Varieties admitting a diagonal splitting exhibit even nicer properties. In this talk I will give an overview over the consequences of the existence of such splittings and then discuss criteria for toric varieties to be diagonally split.
On Thursday, May 31, at 12:45 in L6, a seminar in the Strings Junior series:
Matteo Parisi
Landau-Ginzburg models
On Thursday, May 31, at 13:00 in Dalitz Institute (Denys Wilkinson Building), a seminar in the Dalitz Seminar in Fundamental Physics series:
Rudin Petrossian-Byrne & Hannah Tillim (Oxford)
TBA
On Thursday, May 31, at 16:00 in L6, a seminar in the Number Theory series:
François Charles (Universite Paris-Sud)
Coherent sheaves on arithmetic schemes and basic results on arithmetic ampleness
Further information: We will discuss a basic framework to deal with coherent sheaves on schemes over $\mathbb{Z}$, involving infinite-dimensional results on the geometry of numbers. As an application, we will discuss basic results, old and new, on arithmetic ampleness, such as Serre vanishing, Nakai-Moishezon, and Bertini. This is joint work with Jean-Benoît Bost.
On Thursday, May 31, at 16:15 in Beecroft Seminar Room, a seminar in the Theoretical Particle Physics series:
TBC (TBC)
Beyond the Standard Model: theories & signatures in an experimental era
On Monday, June 4, at 14:00 in Dennis Sciama Lecture Theatre, a seminar in the Astrophysics Colloquia series:
Stan Owocki (University of Delaware)
Breaching the Eddington Limit: Eruptive Mass Loss from Massive Stars
On Monday, June 4, at 14:15 in L4, a seminar in the Geometry and Analysis series:
TBA
On Tuesday, June 5, at 11:30 in Conference Room, DWB, a seminar in the Cosmology series:
TBC
On Tuesday, June 5, at 12:00 in L4, a seminar in the Quantum Field Theory series:
Eli Hawkins (University of York)
A Cohomological Perspective on Algebraic Quantum Field Theory
Further information: 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.
On Tuesday, June 5, at 15:45 in L4, a seminar in the Algebraic Geometry series:
Lenny Taelman (University of Amsterdam)
TBA
Further information: TBA
On Thursday, June 7, at 12:45 in L4, a seminar in the Strings Junior series:
Tomasz Lukowski
Quiver gauge theories
On Friday, June 8, at 14:00 in Dennis Sciama Lecture Theatre, a seminar in the Theoretical Physics Colloquia series:
Jean-Francois Joanny (ISPCI, Paris)
TBC
On Friday, June 8, at 16:00 , a seminar in the Math Colloquium series:
Philip Maini, Edward Morrissey, Heather Harrington (St Anne's College Tsuzuki Lecture theatre)
QBIOX Colloquium
Further information: 1600-1645 - Philip Maini 1645-1705 - Edward Morrissey 1705-1725 - Heather Harrington 1725-1800 - Drinks and networking The talks will be followed by a drinks reception. Tickets can be obtained from https://www.eventbrite.co.uk/e/qbiox-colloquium-trinity-term-2018-ticket... [1]. (As ever, tickets are not necessary, but they do help in judging catering requirements.) PHILIP MAINI Does mathematics have anything to do with biology? In this talk, I will review a number of interdisciplinary collaborations in which I have been involved over the years that have coupled mathematical modelling with experimental studies to try to advance our understanding of processes in biology and medicine. Examples will include somatic evolution in tumours, collective cell movement in epithelial sheets, cell invasion in neural crest, and pattern formation in slime mold. These are examples where verbal reasoning models are misleading and insufficient, while mathematical models can enhance our intuition. EDWARD MORRISEY Fixation and spread of somatic mutations in adult human colonic epithelium Cancer causing mutations must become permanently fixed within tissues. I will describe how, by visualizing somatic clones, we investigated the means and timing with which this occurs in the human colonic epithelium. Modelling the effects of gene mutation, stem cell dynamics and subsequent lateral expansion revealed that fixation required two sequential steps. First, one of around seven active stem cells residing within each colonic gland has to be mutated. Second, the mutated stem cell has to replace neighbours to populate the entire gland. This process takes many years because stem cell replacement is infrequent (around once every 9 months). Subsequent clonal expansion due to gland fission is also rare for neutral mutations. Pro-oncogenic mutations can subvert both stem cell replacement to accelerate fixation and clonal expansion by gland fission to achieve high mutant allele frequencies with age. The benchmarking and quantification of these behaviours allows the advantage associated with different gene specific mutations to be compared and ranked irrespective of the cellular mechanisms by which they are conferred. The age related mutational burden of advantaged mutations can be predicted on a gene-by-gene basis to identify windows of opportunity to affect fixation and limit spread. HEATHER HARRINGTON Comparing models with data using computational algebra In this talk I will discuss how computational algebraic geometry and topology can be useful for studying questions arising in systems biology. In particular I will focus on the problem of comparing models and data through the lens of computational algebraic geometry and statistics. I will provide concrete examples of biological signalling systems that are better understood with the developed methods. [1] https://www.eventbrite.co.uk/e/qbiox-colloquium-trinity-term-2018-tickets-45932427126
On Friday, June 8, at 16:00 in L1, a seminar in the Math Colloquium series:
Sir John Ball (University of Oxford)
Title tbc
Further information: Details to follow
On Monday, June 11, at 14:00 in Dennis Sciama Lecture Theatre, a seminar in the Astrophysics Colloquia series:
Keith Horne (University of St Andrews)
Echo Mapping of Black Hole Accretion Flows in Active Galactic Nuclei
On Monday, June 11, at 14:15 in L4, a seminar in the Geometry and Analysis series:
Jan Sbierski (Oxford)
TBA
On Tuesday, June 12, at 15:45 in L4, a seminar in the Algebraic Geometry series:
Chunyi Li (University of Warwick)
Bogomolov type inequality for Fano varieties with Picard number 1
Further information: I will talk about some basic facts about slope stable sheaves and the Bogomolov inequality.  New techniques from stability conditions will imply new stronger bounds on Chern characters of stable sheaves on some special varieties, including  Fano varieties, quintic threefolds and etc. I will discuss the progress in this direction and some related open problems.
On Thursday, June 14, at 12:45 in L6, a seminar in the Strings Junior series:
Marc-Antoine Fiset
Higher symmetries
On Friday, June 15, at 16:00 in L1, a seminar in the Math Colloquium series:
Alfio Quarteroni (Politecnico di Milano and EPFL Lausanne)
Mathematical and numerical models for heart function
Further information: Mathematical models based on first principles can describe the interaction between electrical, mechanical and fluid-dynamical processes occurring in the heart. This is a classical multi-physics problem. Appropriate numerical strategies need to be devised to allow for an effective description of the fluid in large and medium size arteries, the analysis of physiological and pathological conditions, and the simulation, control and shape optimisation of assisted devices or surgical prostheses. This presentation will address some of these issues and a few representative applications of clinical interest.
On Wednesday, July 4, at 14:30 in L3, a seminar in the Algebraic Geometry series:
Paul Arne Østvær (Oslo)
A^1 contractible varieties
Further information: Motivic homotopy theory gives a way of viewing algebraic varieties and topological spaces as objects in the same category, where homotopies are parametrised  by the affine line.  In particular, there is a notion of $\mathbb A^1$ contractible varieties.  Affine spaces are $\mathbb A^1$ contractible by definition.  The Koras-Russell threefold KR defined by the equation $x + x^2y + z^2 + t^3 = 0$ in $\mathbb A^4$ is the first nontrivial example of an $\mathbb A^1$ contractible smooth affine variety.  We will discuss this example in some detail, and speculate on whether one can use motivic homotopy theory to distinguish between KR and $\mathbb A^3$.
On Friday, October 12, at 16:00 in L1, a seminar in the Math Colloquium series:
Francis Bach (CNRS and Ecole Normale Superieure Paris)
Francis Bach - title tbc
Further information: More details to follow.