# MAGIC055: Integrable Systems

## Course details

### Semester

Spring 2010
Monday, January 11th to Friday, March 19th

### Hours

Live lecture hours
10
Recorded lecture hours
0
Total advised study hours
0

Mondays
13:05 - 13:55

### Announcements

I have uploaded the lecture 4 and 5 and the third problem sheet

## Description

This is MAGIC023 module tought by Marta Mazzocco in 2007-2008 who has recently started her work in Loughborough. This course now is offered by Loughborough University. All necessary materials are available on the MAGIC website.
Description This course starts of from the case of finite dimensional Hamiltonian systems. We shall explain what integrability means in this context. We shall introduce the notion of Liouville integrability and state the Arnol'd-Liouville theorem which roughly speaking says that a system is integrable if admits enough (Poisson commuting) constants of motion. We shall then introduce another fundamental concept of modern mathematics: symmetries produce integrals of motion (Emmy Noether's theorem).
Before moving on to infinite dimensional system we shall study the example of the Manakov system trough its Lax pair. We shall show how from the Lax pair it is straightforward to obtain the needed constants of motion to prove integrability. Here too the role of the symmetries in the system is fundamental. This example will lead us to consider the natural integrable systems which live on the coadjoint orbits of a Lie algebra. We shall then adapt this machinery to the case of pseudo-differential operators in order to study infinite dimensional systems such as the KdV equation. If there is enough time we'll study special solutions of the KdV such as solitons, finite gap solution and self-similar solutions.

### Prerequisites

Analytical mechanics: Hamiltonian and Lagrangian approach. Rigid body equations. Lie algebras: main definitions of Lie algbera and Lie group. Adjoint and co-adjoint action. Differential manifolds: tangent and cotangent bundle, vector fields, differential forms.

### Syllabus

1) Finite dimensional Hamiltonian systems: Recap on Poisson brackets and canonical transformations. Notion of Liouville integrability. Action angle variables for the pendulum. Arnol'd Liouville theorem (no proof). Noether Theorem Example: solution of the Euler top by elliptic integrals. 2) Hamiltonian systems on coadjoint orbits: Lie algebras. Kostant-Kiriillov Poisson brackets. Lax pairs. Hamiltonian structure of Lax equations. Example: Integrability of the Manakov system on so(n). 3) Infinite dimensional Integrable systems: Pseudo-differential operators. Lax pairs for KdV.

## Lecturer

• MM

### Dr Marta Mazzocco

University
Loughborough University

## Bibliography

### Follow the link for a book to take you to the relevant Google Book Search page

You may be able to preview the book there and see links to places where you can buy the book. There is also link marked 'Find this book in a library' - this sometimes works well, but not always - you will need to enter your location, but it will be saved after you do that for the first time.

• Introduction to classical Integrable systems (Babelon, Bernard, Talon, book)

## Assessment

### Attention needed

Assessment information will be available nearer the time.

## Files

Only consortium members have access to these files.