A NEW NULL-PLANE QUANTUM POINCARE ALGEBRA

A new quantum deformation, which we call null-plane, of the (3+1) Poin care algebra is obtained. The algebraic properties of the classical nu ll-plane description are generalized to this quantum deformation. In p articular, the classical isotopy subalgebra of the null-plane is defor med into a Hopf subalgebra, and deformed spin operators having classic al commutation rules can be defined. Quantum Hamiltonian, mass and pos ition operators are studied, and the null-plane evolution is expressed in terms of a deformed Schrodinger equation.