Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Low-energy graceful exit in anisotropic string cosmology backgrounds   We discuss the possibility of a smooth transition from the pre- to the
post-big bang regime, in the context of the lowest-order string effective
action (without higher-derivative corrections), taking into account with a
phenomenological model of source the repulsive gravitational effects due to the
back-reaction of the quantum fluctuations outside the horizon. We determine a
set of necessary conditions for a successful and realistic transition, and we
find that such conditions can be satisfied (by an appropriate model of source),
provided the background is higher-dimensional and anisotropic.

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The categories of this paper are: funct-an
21
The categories of this paper are: adap-org
36
The categories of this paper are: cmp-lg
31
The categories of this paper are: ao-sci
37
The categories of this paper are: supr-con
19
The categories of this paper are: eess
34
The categories of this paper are: chem-ph
32
The categories of this paper are: atom-ph
4
The categories of this paper are: cond-mat
13
The categories of this paper are: quant-ph
12
The categories of this paper are: nucl-th
22
The categories of this paper are: chao-dyn
1
The categories of this paper are: cs
10
The categories of this paper are: q-bio
8
The categories of this paper are: hep-ex
14
The categories of this paper are: math-ph