On the inverse problem of the discrete calculus of variations
arXiv:1808.09086 · doi:10.1088/1751-8121/ab2919
Abstract
In this paper we present an algorithm to find the discrete Lagrangian for an autonomous recurrence relation of arbitrary even order with . The method is based on the existence of a set of differential operators called annihilation operators which can be used to convert a functional equation into a system of linear partial differential equations. This completely solves the inverse problem of the calculus of variations in this setting.
29 pages