3 papers
math-ph2004
Generalisations of the Laplace-Runge-Lenz vector
P. G. L. Leach, G. P. Flessas
The characteristic feature of the Kepler Problem is the existence of the so-called Laplace--Runge--Lenz vector which enables a very simple discussion of the properties of the orbit…
gr-qc2000
Ever-expanding, Isotropizing, Quadratic Cosmologies
Spiros Cotsakis, George Flessas, Peter Leach +1
We consider some aspects of the global evolution problem of Hamiltonian homogeneous, anisotropic cosmologies derived from a purely quadratic action functional of the scalar curvatu…
nlin.SI2000
Symmetry, singularities and integrability in complex dynamics II: Rescaling and time-translation in two-dimensional systems
Peter Leach, Spiros Cotsakis, George Flessas
The explicit integrability of second order ordinary differential equations invariant under time-translation and rescaling is investigated. Quadratic systems generated from the line…