Feynman and Margolus have shown that a closed, locally interacting quantum system is capable of performing deterministic computation. Feynman's system computes in a serial way. Margolus was able to extend Feynman's ideas to get quantum description of a cellular automaton, i.e. a model which...

We present a method for approximating a fitness landscapes as a superposition of "elementary" landscapes. Given a correlation function of the landscape in question we show that the relative amplitudes of contributions with P-ary interactions can be computed. We show an application to RNA free...

The polygamy threshold model states that if costs incurred are less than the benefits gained from a polygamous relationship in terms of male or habitat quality, then polygamy is favored and could evolve. Here we construct mathematical models and computer simulations to evaluate this hypothesis...

Urban centers present all over the world striking similarities which translate into universal laws describing their growth and morphology. In this paper, we study a simple 2-dimensional cellular automata model containing what we identfiy as essential ingredients in the dimographic change. the...

We develop various mathematical models of the clinical latency stage of HIV-1 infection assuming that HIV-1 infection is limited either by the availability of cells that HIV can infect of by a specific anti-HIV cellular immune response. The former models we call "target-cell-limited." Comparing...

We show that voltage-sensitive macromolecules can, by the application of the right type of external voltage fluctuation, be focused with great probability into a desired kinetic substate. As an illustration we consider an eight-state model of the Shaker $K^+$ channel driven by dichotomous...

We look at price formation in a retail setting, that is, companies set prices, and consumers either accept prices or go someplace else. In contrast to most other models in this context, we use a two-dimensional spatial structure for information transmission, that is, consumers can only learn...

Signaling networks are exemplified by systems as diverse as biological cells, economic markets, and the Web. After a discussion of some general characteristics of signaling networks, this paper explores the adaptive evolution of complexity in a simple model of a signaling network. The paper...

In this paper we prove a Faber-Krahn-type inequality for regular trees and give a complete characterization of extremal trees. The main tools are rearrangements and perturbation of regular trees.

We show closed-form analytic functions consisting of a finite number of trigonometric terms can simulate Turing machines, with exponential slowdown in one dimension or in real time in two or more. <p> Key words. dynamical systems, universal computation, iterated maps, analytic functions, Halting...</p>