Tentative schedule of topics for MTH 455, Spring 2005


1 Population models
Text 1a Haberman
Text 1b Ringland, Kopecky: Radioactive decay and SIR infection models
Text 1c Hofbauer, Sigmund


A Discrete One-Species Model (1st order linear difference eqn), geometric growth, Malthus


Struggle for existence, Density-dependent growth


Logistic map, cobweb diagrams, fixed points


linear stability analysis, topological conjugacy, Hartman-Grobman theorem


periodic points, deterministic chaos


Discrete One-Species Models with an Age Distribution, eigenvectors.


Continuous-time models, exponential growth, logistic equation


Stochastic Models. Probability concepts, random processes, realizations, mean and standard deviation.


Comparison of deterministic and stochastic models for radioactive decay and SIR infection model.


Density-Dependent Growth (logistic eqn), Phase Plane Solution of Logistic Equation, Explicit Solution of the Logistic Equation


Linear Constant Coefficient Difference and Differential Equations (incl polar rep of complex numbers)


Growth Models with Time Delays (discrete logistic eqn)


Destabilizing Influence of Delays, delay differential equations (destabilization in delayed SHO)


Two-Species Models


Phase Plane, Equilibrium, and Linearization


Systems of Two Constant Coefficient First Order Differential Equations (306 material)


Stability of Two-Species Equilibrium Populations (TD diagram)


Phase Plane of Linear Systems


Predator Prey Models


Derivation of the Lotka-Volterra Equations


Qualitative Solution of the Lotka-Volterra Equations


Average Populations of Predators and Prey


Man's Influence on Predator-Prey Systems


Limitations of Lotka-Volterra Equation


Two Competing Species


Genetics. Hardy-Weinberg Law.




2 Heat and diffusion. Diffusion Equation (in 1 spatial dimension)
Text 2a Ringland: Heat and diffusion


Thermal equilibrium in rod.


Phase-lag in periodic planet-heating.


Fundamental plane-source solution, and applications (e.g. momentary contact with hot object)




3 Spontaneous Structure and Travelling Waves
Text 3a Ringland: Mass action, Schlogl model, Brusselator
Text 3b Pearson: Complex structure from a simple model
Text 3c Wikipedia: Conway's Automaton
Text 3d Murray 6.5, 12.4: nerve impulses


Chemical reactions: the Principle of Mass Action


A<->B. The Schlogl Model (bistability)


Reaction-Diffusion Systems


Pattern-formation. The Brusselator: homogeneous steady state, spatial structures, spatio-temporal structures


Complex pattern-formation: The Pearson Experiment. (Euler's method, finite-difference approximation of derivatives.)


Conway's Cellular Automaton


Travelling waves. (Linearized Brusselator as example)


Hodgkin-Huxley Theory of Nerve Membranes: Fitzhugh-Nagumo Model


Waves in Excitable Media




4 Vibration: damped and forced oscillators
Text 4a Ringland: Introduction
Text 4b Keener, Sneyd: Models of the cochlea


Coupled SHOs


Elastic bar


Cochlear membrane: pitch discrimination.