Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Cosmologies from higher-order string corrections   We study cosmologies based on low-energy effective string theory with
higher-order string corrections to a tree-level action and with a modulus
scalar field (dilaton or compactification modulus). In the presence of such
corrections it is possible to construct nonsingular cosmological solutions in
the context of Pre-Big-Bang and Ekpyrotic universes. We review the construction
of nonsingular bouncing solutions and resulting density perturbations in
Pre-Big-Bang and Ekpyrotic models. We also discuss the effect of higher-order
string corrections on dark energy universe and show several interesting
possibilities of the avoidance of future singularities.

11
The categories of this paper are: hep-lat
1
The categories of this paper are: cs
17
The categories of this paper are: q-fin
18
The categories of this paper are: econ
32
The categories of this paper are: atom-ph
33
The categories of this paper are: plasm-ph
37
The categories of this paper are: supr-con
28
The categories of this paper are: alg-geom
2
The categories of this paper are: math
26
The categories of this paper are: bayes-an
25
The categories of this paper are: patt-sol
27
The categories of this paper are: comp-gas
9
The categories of this paper are: nlin
8
The categories of this paper are: hep-ex
35
The categories of this paper are: mtrl-th
36
The categories of this paper are: cmp-lg