Parity and Fermions in Front-Form: An Unexpected Result
  We show that under the operation of parity the {\it front-form} $(1/2,\,0)$ and $(0,\,1/2)$ Weyl spinors (massive or massless) do not get interchanged. This has the important consequence that if a front-form theory containing $(1/2,\,0)\oplus(0,\,1/2)$ representation space has to be parity covariant then one must study the evolution of a physical system not only along $x^+$ but also along the $x^-$ direction. As a result of our analysis, we find an indication that there may be no halving of the degrees of freedom in the front form of field theories. 
Mikolaj Sawicki and D. V. Ahluwalia