Past Events

In general Topological Quantum Field Theories are very diverse, but we may focus on low dimensional cases. As a starting point, we'll give a complete classification of 1-dimensional TQFTs. To this end, I'll present a review of dualization in a...

It is well-known that a function 𝑢=𝑢(𝑡,𝑥)u=u(t,x) describing the behavior of acoustic or electromagnetic waves in time and space can often be decomposed as an infinite sum 𝑢(𝑡,𝑥)=∑𝑛=1∞𝑐𝑛(𝑡)𝜓𝑛(𝑥) ,u(t,x)=∑n=1∞cn(t)ψn(x) , where each term in the sum is...

Idempotent semirings have been relevant in several branches of applied mathematics, like formal languages and combinatorial optimization. They were brought recently to pure mathematics thanks to its link with tropical geometry, which is a relatively...

geometry and singularity theory. For example, one can enrich spectra of rings with new points coming from valuations defined on them and taking values in totally ordered abelian groups. Totally ordered groups are examples of idempotent semirings, and...

I will describe a new approach for exhaustively generating combinatorial objects by combining a satisfiability (SAT) solver with an isomorph-free exhaustive generation method such as orderly generation. The SAT solver is able to limit the search to...

Random high-dimensional cost functions and random probability distributions arise in a number of applied fields. For instance, in high-dimensional statistics, an M-estimator is the solution of a random optimization problem (the randomness being...

Sampling is a fundamental and widespread algorithmic primitive that lies at the heart of Bayesian inference and scientific computing, among other disciplines. Recent years have seen a flood of works aimed at laying down the theoretical underpinnings...

Chern-Simons theory, as introduced by Witten, is a three dimensional quantum gauge theory associated to a compact simple Lie group and a level. The mathematical model of this theory as a topological quantum field theory was introduced by Reshetikhin...

Abstract polytopes are a combinatorial generalisation of classical objects that were already studied by the greeks. They consist in posets satisfying some extra axioms. Their rank is roughly speaking the number of layers the poset has. When they have...

Curvature is one of the fundamental ingredients in differential geometry. People are increasingly interested in whether it is possible to think of combinatorial graphs as manifolds and a number of different notions of curvature have been proposed. I...