Resumo:
We investigate systems with color Lie (super) algebra symmetries. As an
example we consider the symmetries of the Levy-Leblond equation, which is
a non-relativistic wave equation of a spin 2 1 particle.
It is shown that the equation has two kinds of symmetries. One is given
by the super Schroedinger algebra and the other one by a Z 2 × Z 2 graded Lie
superalgebra. This structure acommodate all the symmetry operators of the
equation and it is a simple example of the Z 2 × Z 2 symmetries of an equation
where all graded subspaces are not empty.