The Preferred Frame and Poincare Symmetry
  In this paper we describe a covariant canonical formalism for a free time-like (massive) as well as space-like (tachyonic) particle in the framework of nonstandard synchronization scheme. In this scheme one is able to introduce absolute causality without breaking the Poincar\'e invariance. 
Jakub Rembielinski and Pawel Caban