FUNCTIONAL REALIZATIONS OF LIE ALGEBRAS AS NOETHER POINT SYMMETRIES OF SYSTEMS

Functional realizations of Lie algebras are applied to the problem of determining Lie and Noether point symmetries of Lagrangian systems in N dimensions, particularly in the plane. This encompasses both the case of symmetry-preserving perturbations of a given system, as well as the generic analysis on the structure of (regular) Lagrangians in order to admit a symmetry algebra belonging to a specific isomorphy class.