Asymptotic estimates of SARS-CoV-2 infection counts and their sensitivity to stochastic perturbation

Since the outbreak of the coronavirus, modellers from around the world have scrambled to predict the course of its spread, projecting forward from data on past infections and deaths in any region. Such estimates help public health officials and governments to judge the possible risks they face, and, on their basis, many nations have imposed restrictive social confinement measures. Read more

The effect of social balance on social fragmentation

Nations and communities typically function as relatively coherent groups, yet also occasionally fall apart or fragment into highly polarised sub-groups. Read more

Phase transitions in atypical systems induced by a condensation transition on graphs

Random graphs can undergo structural phase transitions as a function of their model parameters. For example, in the well-known percolation transition, a network-spanning cluster of linked nodes abruptly appears at a critical value of the probability, c, for a link to exist between any pair of nodes. Read more

A percolation model for the emergence of the Bitcoin Lightning Network

The distributed ledger system known as blockchain has triggered a revolution in the payments industry, and is the technological infrastructure underlying cryptocurrencies such as Bitcoin. Even so, the blockchain concept itself faces some limitations which may hinder its future growth and adoption. Read more

Approximate Uncertain Programs

Uncertain programs are optimization problems involving uncertainties in constraints or objectives. In the past few decades, such programs have been applied in areas from economics and management to automotive control and machine learning. Read more

Escape from model-land

Policy makers in areas ranging from public health to weather forecasting or economics rely on mathematical models to inform their decisions. As models grow more complex and powerful, one might expect, they should contribute to better decisions. Read more

Bifurcations on Fully Inhomogeneous Networks

One of the most powerful methods of bifurcation theory is centre manifold reduction, in which a judicious coordinate change greatly simplifies the analysis of dynamical systems in the vicinity of a bifurcation point. Read more

Superextreme Waves Generation in the Linear Regime

So-called extreme or rogue waves are large amplitude waves which appear unpredictably in optical and acoustic systems, in plasmas, as well as in quantum physics and in hydrodynamics. Read more

Should We Be Afraid of Artificial Intelligence?

Economists worry about the impact that artificial intelligence (AI) technology could have as it begins to displace human employees, especially those in entry-level jobs such as data entry, customer service or retail. Read more

Diagnosing concurrent drivers of weather extremes: application to warm and cold days in North America

Extreme weather events emerge out of the interaction of many physical processes, and understanding how is a key challenge in atmospheric science. Read more