Generalized Dirac Equation for a particle in a gravitational field

The existence of a minimal observable length modifies the Heisenberg’s uncertainty principle at Plank scales and leads to some modifications of the Dirac equation. Here, we consider the generalized uncertainty principle (GUP) theory in order to deduce a generalized Dirac equation and solve its eigenvalue problem for a particle within a gravitational field created by a central mass. We use two different approximations to tackle the problem, based on the Schwarzschild and a modified Schwarzschild metrics.