A Dynamical Mechanism for the Big Bang and Non-Regularizability for   $w=1$
  We consider a contracting universe and its transition to expansion through the big bang singularity with a time varying equation of state $w$, where $w$ approaches $1$ as the universe contracts to the big bang. We show that this singularity is non-regularizable. That is, there is no unique extension of the physical quantities after the transition, but rather infinitely many. This is entirely different from the case of $w > 1$ studied in \cite{Xue:2014}, where $w$ approaches a constant value $w_c > 1$ as the universe contracts. In that case a continuous transition through the big bang to yield a unique extension was possible only for a discrete set of $w_c$ satisfying coprime conditions. We also show that there exists another time variable, $N$, at the big bang singularity itself, at $t=0$, where $w$, varies as a function of $N$. This defines an {\em extended big bang state}. Within it, $H$ is infinity. In the extended state, $w$ varies from a universe dominated by the cosmological constant to $1$. After $w$ reaches $1$ then the big bang occurs and time $t >0$ resumes. This gives a dynamical mechanism for the big bang that is mathematically complete as a function of $N$. Dynamical systems methods are used with classical modeling. 
Edward Belbruno
gr-qc hep-th math.DS