Journal of Non-linear Mathematical Physics

ISSN: 1402-9251
Volume 5, Issue 4, November 1998
J. CASAHORRÁN
Pages: 371 - 382
We analyse the behaviour of the Dirac equation in d = 1 + 1 with Lorentz scalar potential. As the system is known to provide a physical realization of supersymmetric quantum mechanics, we take advantage of the factorization method in order to enlarge the restricted class of solvable problems. To be...
Peter E. HYDON
Pages: 405 - 416
This paper describes a new algorithm for determining all discrete contact symmetries of any differential equation whose Lie contact symmetries are known. The method is constructive and is easy to use. It is based upon the observation that the adjoint action of any contact symmetry is an automorphism...
W.W. ZACHARY, V.M. SHTELEN
Pages: 417 - 437
A concept of asymptotic symmetry is introduced which is based on a definition of symmetry as a reducibility property relative to a corresponding invariant ansatz. It is shown that the nonlocal Lorentz invariance of the free-particle Schrödinger equation, discovered by Fushchych and Segeda in 1977,...