The formal structure of evolutionary theory is based upon the dynamics of alleles, individuals and populations. As such, the theory must assume the prior existence of these entities. This existence problem was recognized nearly a century ago, when DeVries (1904) stated, ``Natural selection may...

The structure and evolution of the protein interaction network of the yeast Saccharomyces cerevisiae is analyzed. The network is viewed as a graph whose nodes correspond to proteins. Two proteins are connected by an edge if they interact. The network resembles a random graph, in that it consists...

We show that predicting the HPP or FHP III lattice gas for finite time is equivalent to calculating the output of an arbitrary Boolean circuit, and is therefore P-complete: that is, it is just as hard as any other problem solvable by a serial computer in polynomial time. <p> It is widely believed...</p>

Since the classic work of Feyerabend and Kuhn, the role of social factors in the scientific enterprise has been a major concern in the philosophy and history of science. In particular, the presence of social factors such as the desire for prestige or pressures to conform to accepted ideas, have...

Inefficient delays in trades can sometimes be observed after the arrival of important public news. This paper explains these phenomena with a model in which agents defer trades in the fear that they may be taken advantaged of by better informed trading partners. Under certain conditions, delay...

In the framework of the median voter theorem, an ideologically driven candidate can fully alter policy when running against a vote-maximizing oponent. When turnout is allowed to depend on the relative positioning of the ideal points of the candidates relative to the voter, this result need not...

General equilibrium theory in economics defines the relative prices for goods and services, but does not fix the absolute values of prices. We present a theory of money in which the value of money is a time dependent "strategic variable," to be chosen by the individual agents. The idea is...

This paper reviews the evolution of trading structures by examining two pertinent strands in the literature on economics with interacting agents, one, works that presume a specified topology of interactions among agents, and two, works that let random mechanisms determine that topology. The papr...

This paper presents a day-to-day re-routing relaxation approach for traffic simulations. Starting from an initial planset for the routes, the route-based microsimulation is exxecuted. The result of the microsimulation is fed into a re-router, which re-routes a certain percentage of all trips....

This paper proves that one can not build a computer which can, for any physical system, take the specification of that system's state as input and then correctly predict its future state before that state actually occurs. Loosely speaking, this means that one can not build a physical computer...