Event
Pavel Winternitz, Universit茅 de Montr茅al, Centre de Recherches Math茅matiques
Tuesday, January 30, 2018 15:30
Room 4336, Pav. Andr茅-Aisenstadt, 2920, ch. de la Tour, CA
Lie group classification of first-order delay ordinary differential equations.
A group classification of first-order delay ordinary differential equation (DODE) accompanied by an equation for the delay parameter (delay relation) is presented. A subset of such systems (DODS) which consists of a linear DODEs and solution independent delay relations have infinite-dimensional symmetry algebras, as do nonlinear ones that are linearizable by an invertible transformation of variables. Genuinely nonlinear DODS have symmetry algebras of dimension n, 0 鈮� n 鈮� 3. It is shown how exact analytical solutions of invariant DODS can be obtained using symmetry reduction. This is joint work with Vladimir A. Dorodnitsyn, Roman Kozlov, and Sergey V. Meleshko.