Perturbation theory and calculus of variations (840G1)

15 credits, Level 6

Spring teaching

The aim of this module is to introduce you to a variety of techniques primarily involving ordinary differential equations, that have applications in various branches of applied mathematics. No particular application is emphasised.

Topics covered include –

Dimensional analysis and scaling:

  • physical quantities and their measurement
  • dimensions
  • change of units
  • physical laws
  • Buckingham Pi Theorem
  • scaling.

Regular perturbation methods:

  • direct method applied to algebraic equations and initial value problems (IVP)
  • Poincar method for periodic solutions
  • validity of approximations.

Singular perturbation methods:

  • finding approximate solutions to algebraic solutions
  • finding approximate solutions to boundary value problems (BVP) including boundary layers and matching.

Calculus of Variations:

  • necessary conditions for a function to be an extremal of a fixed or free end point problem involving a functional of integral form
  • isoperimetric problems.


100%: Lecture


20%: Coursework (Problem Set)
80%: Examination (Unseen examination)

Contact hours and workload

We’re currently reviewing contact hours for modules and will update with further information as soon as it is available.

This module is running in the academic year 2019/20. We also plan to offer it in future academic years. It may become unavailable due to staff availability, student demand or updates to our curriculum. We’ll make sure to let our applicants know of such changes to modules at the earliest opportunity.


This module is offered on the following courses: