5 papers
Height representation, critical exponents, and ergodicity in the four-state triangular Potts antiferromagnet
Cristopher Moore, M. E. J. Newman
We study the four-state antiferromagnetic Potts model on the triangular lattice. We show that the model has six types of defects which diffuse and annihilate according to certain c…
Extinction, diversity and survivorship of taxa in the fossil record
M. E. J. Newman, Paolo Sibani
Using data drawn from large-scale databases, a number of interesting trends in the fossil record have been observed in recent years. These include the average decline in extinction…
Decline in extinction rates and scale invariance in the fossil record
M. E. J. Newman, Gunther J. Eble
We show that the decline in the extinction rate during the Phanerozoic can be accurately parameterized by a logarithmic fit to the cumulative total extinction. This implies that ex…
Effects of neutral selection on the evolution of molecular species
M. E. J. Newman, Robin Engelhardt
We introduce a new model of evolution on a fitness landscape possessing a tunable degree of neutrality. The model allows us to study the general properties of molecular species und…
New Monte Carlo algorithms for classical spin systems
G. T. Barkema, M. E. J. Newman
We describe a number of recently developed cluster-flipping algorithms for the efficient simulation of classical spin models near their critical temperature. These include the algo…