The universal pathway to innovative urban economies

As centres of human population and civilisation, cities have pushed the boundaries of human productivity and innovation. Read more

Extreme value theory for constrained physical systems

Many stochastic processes in natural and man-made systems exhibit occasional extreme events which are rare in comparison to usual outcomes. Though infrequent, such events can still carry decisive weight. Read more

Narrative structure of A Song of Ice and Fire creates a fictional world with realistic measures of social complexity

The global television hit Game of Thrones, first aired in 2011, was inspired by a series of fantasy books written by George R. R. Martin. Since publication in 1996, A Song of Ice and Fire has been translated into more than 45 languages, and established a unique niche in the world of storytelling. Read more

Using posterior predictive distributions to analyse epidemic models: COVID-19 in Mexico City

Scientists and public health officials have relied on a variety of epidemiological models to forecast the trajectory of the coronavirus pandemic, and to derive guidance for policies aiming to avoid overloading health facilities. All such models contain parameters, and forecasting tools tend to choose these to provide a best fit to available observations. Read more

Modeling the second wave of COVID-19 infections in France and Italy via a stochastic SEIR model

Late in the spring of this year, many nations around the world, especially in Europe, faced public health crises, as coronavirus infections threatened to overwhelm their intensive care facilities. Authorities responded with drastic measures to reduce social contacts, closing businesses and schools, restricting public transport and banning large social events. Read more

Spatiotemporal seismic hazard and risk assessment of M9.0 megathrust earthquake sequences of wood‐frame houses in Victoria, British Columbia, Canada

Large earthquakes and the aftershocks they generate cause considerable damage to buildings. As a result, risk management, evacuation planning and rapid seismic loss estimation require good estimates of the cumulative damage likely to arise from an earthquake sequence. This is especially important in geographical regions of extreme risk. Read more

Topological Comparison Between the Stochastic and the Nearest‐Neighbor Earthquake Declustering Methods Through Network Analysis

On short timescales, earthquakes cluster in both time and space, eventually complicating the analysis of seismicity. One basic goal is to partition the earthquake catalogue into two classes of events — background events, regarded as spontaneous or independent earthquakes, and clustered events, including events triggered by other earthquakes. Read more

The spectral density of dense random networks and the breakdown of the Wigner semicircle law of random matrix theory

The theory of random networks is useful in modelling systems of many interacting units, ranging from neurons in the brain and computers and routers in the Internet to species in an ecosystem. In this theory, a key mathematical quantity is the eigenvalue spectrum of the adjacency matrix, the entries of which reflect the connections between different network elements. Read more

An attempt to explain recent changes in European snowfall extremes

In recent decades, the frequency of extreme snowfall events – often entailing considerable human and economic costs – has remained mostly unchanged, despite consistently rising global temperatures. Read more

Optical Tweezers: A Comprehensive Tutorial from Calibration to Applications

A highly-focused laser beam can be used to trap microscopic particles. In this technique – known as optical tweezers – forces arise near the focal spot due to radiation pressure of the light beam (acting along the beam direction) and gradient forces which pull the particle towards the high-intensity focal spot. Read more