The following discussion is meant to give some more formalism to students of the Variational Principles course and perhaps tie it to material that they might have come across in analysis or linear algebra courses.

This page is a work in progress and may not be accurate; formulae may have …

What is a variational principle?

A variational principle is a mathematical or physical law expressed in terms of maximising or minimising a certain quantity. The simplest example was known to ancient Egyptian builders and surveyers: a taut rope stretched between two points takes the shape that minimises its length. This …