The Density Matrix Deformation in Physics of the Early Universe and Some   of its Implications
  In this paper a new approach to investigation of Quantum and Statistical Mechanics of the Early Universe (Planck scale) - density matrix deformation - is proposed. The deformation is understood as an extension of a particular theory by inclusion of one or several additional parameters in such a way that the initial theory appears in the limiting transition... 
Alex E. Shalyt-Margolin