The Majorana spinor representation of the Poincare group

TL;DR

This paper demonstrates that Majorana spinor fields form unitary irreducible projective representations of the Poincare group on real Hilbert spaces, extending the understanding of spinor representations beyond complex spaces.

Contribution

It establishes that Majorana spinor fields with finite mass are unitary irreducible representations of the Poincare group on real Hilbert spaces, and suggests broader applications to arbitrary spins.

Findings

Majorana spinor fields form irreducible representations of the Poincare group.

Majorana-Fourier and Majorana-Hankel transforms relate to momentum operators.

Results enable studying arbitrary spin representations on real Hilbert spaces.

Abstract

There are Poincare group representations on complex Hilbert spaces, like the Dirac spinor field, or real Hilbert spaces, like the electromagnetic field tensor. The Majorana spinor is an element of a 4 dimensional real vector space. The Majorana spinor field is a space-time dependent Majorana spinor, solution of the free Dirac equation. The Majorana-Fourier and Majorana-Hankel transforms of Majorana spinor fields are defined and related to the linear and angular momenta of a spin one-half representation of the Poincare group. We show that the Majorana spinor field with finite mass is an unitary irreducible projective representation of the Poincare group on a real Hilbert space. Since the Bargmann-Wigner equations are valid for all spins and are based on the free Dirac equation, these results open the possibility to study Poincare group representations with arbitrary spins on real Hilbert spaces.