A new class of Fermionic Projectors: M{\o}ller operators and mass   oscillation properties
  Recently, a new functional analytic construction of quasi-free states for a self-dual CAR algebra has been presented in \cite{Felix2}. This method relies on the so-called strong mass oscillation property. We provide an example where this requirement is not satisfied, due to the nonvanishing trace of the solutions of the Dirac equation on the horizon of Rindler space, and we propose a modification of the construction in order to weaken this condition. Finally, a connection between the two approaches is built. 
Nicol\`o Drago and Simone Murro
math-ph gr-qc math.MP math.OA math.SP