Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: 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.

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The categories of this paper are: patt-sol
36
The categories of this paper are: cmp-lg
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The categories of this paper are: quant-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: atom-ph
4
The categories of this paper are: cond-mat
35
The categories of this paper are: mtrl-th
12
The categories of this paper are: nucl-th
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The categories of this paper are: stat
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The categories of this paper are: supr-con
6
The categories of this paper are: astro-ph
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The categories of this paper are: eess
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The categories of this paper are: dg-ga
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The categories of this paper are: physics
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The categories of this paper are: adap-org
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The categories of this paper are: acc-phys