Preface |
Introduction / 1: |
Ordinary differential equations / I: |
Point transformations and their generators / 2: |
One-parameter groups of point transformations and their infinitesimal generators / 2.1: |
Transformation laws and normal forms of generators / 2.2: |
Extensions of transformations and their generators / 2.3: |
Multiple-parameter groups of transformations and their generators / 2.4: |
Exercises / 2.5: |
Lie point symmetries of ordinary differential equations: the basic definitions and properties / 3: |
The definition of a symmetry: first formulation / 3.1: |
Ordinary differential equations and linear partial differential equations of first order / 3.2: |
The definition of a symmetry: second formulation / 3.3: |
Summary / 3.4: |
How to find the Lie point symmetries of an ordinary differential equation / 3.5: |
Remarks on the general procedure / 4.1: |
The atypical case: first order differential equations / 4.2: |
Second order differential equations / 4.3: |
Higher order differential equations. The general nth order linear equation / 4.4: |
How to use Lie point symmetries: differential equations with one symmetry / 4.5: |
First order differential equations / 5.1: |
Higher order differential equations / 5.2: |
Some basic properties of Lie algebras / 5.3: |
The generators of multiple-parameter groups and their Lie algebras / 6.1: |
Examples of Lie algebras / 6.2: |
Subgroups and subalgebras / 6.3: |
Realizations of Lie algebras. Invariants and differential invariants / 6.4: |
Nth order differential equations with multiple-parameter symmetry groups: an outlook / 6.5: |
How to use Lie point symmetries: second order differential equations admitting a G[subscript 2] / 6.6: |
A classification of the possible subcases, and ways one might proceed / 7.1: |
The first integration strategy: normal forms of generators in the space of variables / 7.2: |
The second integration strategy: normal forms of generators in the space of first integrals / 7.3: |
Summary: Recipe for the integration of second order differential equations admitting a group G[subscript 2] / 7.4: |
Examples / 7.5: |
Second order differential equations admitting more than two Lie point symmetries / 7.6: |
The problem: groups that do not contain a G[subscript 2] / 8.1: |
How to solve differential equations that admit a G[subscript 3] IX / 8.2: |
Example / 8.3: |
Higher order differential equations admitting more than one Lie point symmetry / 8.4: |
The problem: some general remarks / 9.1: |
First integration strategy: normal forms of generators in the space(s) of variables / 9.2: |
Second integration strategy: normal forms of generators in the space of first integrals. Lie's theorem / 9.3: |
Third integration strategy: differential invariants / 9.4: |
Systems of second order differential equations / 9.5: |
The corresponding linear partial differential equation of first order and the symmetry conditions / 10.1: |
Example: the Kepler problem / 10.2: |
Systems possessing a Lagrangian: symmetries and conservation laws / 10.3: |
Symmetries more general than Lie point symmetries / 10.4: |
Why generalize point transformations and symmetries? / 11.1: |
How to generalize point transformations and symmetries / 11.2: |
Contact transformations / 11.3: |
How to find and use contact symmetries of an ordinary differential equation / 11.4: |
Dynamical symmetries: the basic definitions and properties / 11.5: |
What is a dynamical symmetry? / 12.1: |
Examples of dynamical symmetries / 12.2: |
The structure of the set of dynamical symmetries / 12.3: |
How to find and use dynamical symmetries for systems possessing a Lagrangian / 12.4: |
Dynamical symmetries and conservation laws / 13.1: |
Example: L = (x[superscript 2] + y[superscript 2])/2 - a(2y[superscript 3] + x[superscript 2]y), a [characters not producible] 0 / 13.2: |
Example: geodesics of a Riemannian space - Killing vectors and Killing tensors / 13.3: |
Systems of first order differential equations with a fundamental system of solutions / 13.5: |
The problem / 14.1: |
The answer / 14.2: |
Systems with a fundamental system of solutions and linear systems / 14.3: |
Partial differential equations / 14.5: |
Lie point transformations and symmetries / 15: |
The definition of a symmetry / 15.1: |
How to determine the point symmetries of partial differential equations / 15.4: |
How to use Lie point symmetries of partial differential equations I: generating solutions by symmetry transformations / 16.1: |
The structure of the set of symmetry generators / 17.1: |
What can symmetry transformations be expected to achieve? / 17.2: |
Generating solutions by finite symmetry transformations / 17.3: |
Generating solutions (of linear differential equations) by applying the generators / 17.4: |
How to use Lie point symmetries of partial differential equations II: similarity variables and reduction of the number of variables / 17.5: |
Similarity variables and how to find them / 18.1: |
Conditional symmetries / 18.3: |
How to use Lie point symmetries of partial differential equations III: multiple reduction of variables and differential invariants / 18.5: |
Multiple reduction of variables step by step / 19.1: |
Multiple reduction of variables by using invariants / 19.2: |
Some remarks on group-invariant solutions and their classification / 19.3: |
Symmetries and the separability of partial differential equations / 19.4: |
Some remarks on the usual separations of the wave equation / 20.1: |
Hamilton's canonical equations and first integrals in involution / 20.3: |
Quadratic first integrals in involution and the separability of the Hamilton-Jacobi equation and the wave equation / 20.4: |
Contact transformations and contact symmetries of partial differential equations, and how to use them / 20.5: |
The general contact transformation and its infinitesimal generator / 21.1: |
Contact symmetries of partial differential equations and how to find them / 21.2: |
Remarks on how to use contact symmetries for reduction of variables / 21.3: |
Differential equations and symmetries in the language of forms / 21.4: |
Vectors and forms / 22.1: |
Exterior derivatives and Lie derivatives / 22.2: |
Differential equations in the language of forms / 22.3: |
Symmetries of differential equations in the language of forms / 22.4: |
Lie-Backlund transformations / 22.5: |
Why study more general transformations and symmetries? / 23.1: |
Finite order generalizations do not exist / 23.2: |
Lie-Backlund transformations and their infinitesimal generators / 23.3: |
Examples of Lie-Backlund transformations / 23.4: |
Lie-Backlund versus Backlund transformations / 23.5: |
Lie-Backlund symmetries and how to find them / 23.6: |
The basic definitions / 24.1: |
Remarks on the structure of the set of Lie-Backlund symmetries / 24.2: |
How to find Lie-Backlund symmetries: some general remarks / 24.3: |
Examples of Lie-Backlund symmetries / 24.4: |
Recursion operators / 24.5: |
How to use Lie-Backlund symmetries / 24.6: |
Similarity solutions for Lie-Backlund symmetries / 25.1: |
Lie-Backlund symmetries and conservation laws / 25.3: |
Lie-Backlund symmetries and generation methods / 25.4: |
A short guide to the literature / 25.5: |
Solutions to some of the more difficult exercises / Appendix B: |
Index |
Preface |
Introduction / 1: |
Ordinary differential equations / I: |