Anisotropy in the cosmic acceleration inferred from supernovae.
 Rameez, M Philosophical transactions. Series A, Mathematical, physical, and engineering sciences volume 383 issue 2290 20240032 (13 Feb 2025) doi:10.1098/rsta.2024.0032
Classification of finite depth objects in bicommutant categories via anchored planar algebras
 Henriques, A Penneys, D Tener, J Communications in Mathematical Physics
Thu, 28 May 2026

16:00 - 17:00
L5

The Viability of Blockchain Markets under Discrete Clearing and Paid Priority

Fayçal Drissi
Abstract

This paper develops a model to evaluate the viability of blockchain markets as the sole venue for price formation. Blockchains clear at discrete intervals called block time, and transactions are executed sequentially according to priority fees paid by traders who compete for queue position.  We show that these features undermine the viability of markets. Paid-priority ordering induces endogenous selection, where only traders with sufficiently high valuations participate. The participation cutoff rises with competition, which intensifies with lower information costs or higher liquidity demand. This hinders price discovery and biases prices. It also impairs liquidity: the cutoff concentrates trading among aggressive traders and increases adverse selection that liquidity suppliers absorb in a single clearing round. Although longer block times enhance consensus security, they amplify these effects and can cause markets to shut down.

 


 

Mon, 19 Jan 2026

16:30 - 17:30
L4

Towards Computational Topological (Magneto)Hydrodynamics: long term computation of fluids and plasma

Kaibo Hu
((Mathematical Institute University of Oxford))
Abstract
From Kelvin and Helmholtz to Arnold, Khesin, and Moffatt, topology has drawn increased attention in fluid dynamics. Quantities such as helicity and enstrophy encode knotting, topological constraints, and fine structures such as turbulence energy cascades in both fluid and MHD systems. Several open scientific questions, such as corona heating, the generation of magnetic fields in astrophysical objects, and the Parker hypothesis, call for topology-preserving computation. 
 
In this talk, we investigate the role of topology (knots and cohomology) in computational fluid dynamics by two examples: relaxation and dynamo. We investigate the question of “why structure-preservation” in this context and discuss some recent results on topology-preserving numerical analysis and computation. Finite Element Exterior Calculus sheds light on tackling some long-standing challenges and establishing a computational approach for topological (magneto)hydrodynamics.

 
$L^2$ and $L^\infty$ rational approximation
 Ackermann, M Reiter, S Trefethen, L (29 Dec 2025)
Topological Data Analysis Detects Percolation Thresholds in Arctic Melt-Pond Evolution
 Offord, W Coughlan, M Hewitt, I Harrington, H Grindstaff, G (15 Dec 2022) doi:10.48550/arxiv.2212.07961
Topological Data Analysis Detects Percolation Thresholds in Arctic Melt-Pond Evolution
 Offord, W Coughlan, M Hewitt, I Harrington, H Grindstaff, G (15 Dec 2022) doi:10.48550/arxiv.2212.07961
Topological Data Analysis Detects Percolation Thresholds in Arctic Melt-Pond Evolution
 Offord, W Coughlan, M Hewitt, I Harrington, H Grindstaff, G (15 Dec 2022) doi:10.48550/arxiv.2212.07961
Mon, 02 Feb 2026
14:15
L4

Non-generic neck pinching in Lagrangian mean curvature flow

Spandan Ghosh
((Mathematical Institute University of Oxford))
Abstract
Lagrangian mean curvature flow (LMCF) is a way to deform a Lagrangian submanifold inside a Calabi--Yau manifold according to the negative gradient of the area functional. There are influential conjectures about LMCF due to Thomas--Yau and Joyce, describing the long-time behaviour and singularities of the flow. By foundational work of Neves, Type I singularities are ruled out under mild assumptions, so it is important to construct examples of Type II singularities with a given blow-up model. In this talk, we describe a general method to construct examples of Lawlor neck pinching in LMCF in complex dimension at least 3. We employ a P.D.E. based approach to solve the problem, as an example of 'parabolic gluing'. The main technical tool we use is the notion of manifolds with corners and a-corners, as introduced by Joyce following earlier work of Melrose. Time permitting, we will discuss how one may construct examples of generic neck pinching.
Subscribe to