Non-extensive distributions for a relativistic Fermi gas

•Tsallis distributions in a relativistic Fermi gas with antiparticles.•Non extensive relations on the Fermi surface.•Non extensive cuts in single particle distributions in momentum space.

Recently the non-extensive approach has been used in a variety of ways to describe dense nuclear matter. They differ in the methods of introducing the appropriate non-extensive single particle distributions inside a relativistic many-body system, in particular when one has to deal both with particles and antiparticles, as in the case of quark matter exemplified in the NJL approach. I present and discuss in detail the physical consequences of the methods used so far, which should be recognized before any physical conclusions can be reached from the results presented.