Asymptotic properties of spinors in general relativity

The author propose a physical intrepretation of the positive energy program by considering it from the point of view of an experiment in which Witten's spinor field, satisfying a second order wave equation, plays the role of detector. He first establish a canonical formalism for a second order wave equation for the spin 1/2 field in a 3 + 2 de Sitter space-time. The author find that the wave equation must be the singleton dipole equation. The resulting field theory exhibits a very interesting dynamics at the boundary. The author study the Hamiltonian of the system and we discover that, after imposing the Lorentz condition, it reduces to an integral over a two-dimensional surface at spatial infinity. The author extend the formalism to asymptotically de Sitter space times, finding features similar to the pure de Sitter case. The author discuss our results and comment on possible improvements