#### Introduction

This is an introductory course on dynamical systems mainly concerned with linear systems and one and two dimensional nonlinear systems of differential equations. We will investigate how to determine the qualitative behaviour of the solutions of these differential equations, without having to determine the actual solutions explicitly (most interesting equations do not have neat closed form solutions). This is an applied mathematics course, and the main focus of the course will be on understanding and explaining the behaviour of solutions to differential equations, as opposed to a pure mathematics course where the focus might be more on stating and proving theorems. The honours version of the course will contain more analytical questions.

The material in this course complements the material in math263/math315/math325. In those courses you learn solve the few differential equations for which neat closed form solutions can be written down, but you do not learn a formula for solving all differential equations, because no such formula exists. In this course we will give an introduction to the techniques for investigating the behaviour of the solutions of differential equations in the cases where neat formulae for the solutions cannot be written down (that is most of the time, in the real world). The final chapter of the recommended text for math315/math325 gives an introduction to the material in math326/376, so if you are planning on taking both math326/376 and math263/math315/math325 I would suggest taking math263/math315/math325 first or both first in the same semester, if your schedule allows. However, formally math263/math315/math325 is not a pre- or co-requisite for this course, and it is quite possible to take this course without the other one.

#### Topics

Linear systems of differential equations, linear stability theory. Nonlinear systems: existence and uniqueness, numerical methods, one and two dimensional flows, phase space, limit cycles, Poincare-Bendixson theorem, bifurcations, Hopf bifurcation, the Lorenz equations and chaos.

#### Audience/Prerequisites

The course is intended for all students with an interest in nonlinear dynamics, and sufficient mathematical grounding. In the past students have been drawn from across science and engineering as well as mathematics. To that end the prerequisites are

• Math 222 or equivalent (Taylor's theorem in particular)
• Math 223 (non-math students), Math 236 (math students), or equivalent (Eigenvalues/eigenvectors in particular)

#### References

The Textbook for this course is

• Nonlinear Dynamics and Chaos, by Steven H Strogatz.
We will largely follow the text in order, covering most of the the first 8 chapters with selected topics from the rest of the book.

#### MyCourses

This class will be run using MyCourses and you will need to be registered to receive e-mail announcements, and to receive assignments. This page is only intended to provide information to students considering registering and will not be updated after the course commences.

#### Further Information

• The first lecture will be on Tuesday 5th September 11.30am-1.00pm in BURN-1B36.
• Course Outline