Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Cosmic Acceleration and the String Coupling   In the context of a cosmological string model describing the propagation of
strings in a time-dependent Robertson-Walker background space-time, we show
that the asymptotic acceleration of the Universe can be identified with the
square of the string coupling. This allows for a direct measurement of the
ten-dimensional string coupling using cosmological data. We conjecture that
this is a generic feature of a class of non-critical string models that
approach asymptotically a conformal (critical) sigma model whose target space
is a four-dimensional space-time with a dilaton background that is linear in
sigma-model time. The relation between the cosmic acceleration and the string
coupling does not apply in critical strings with constant dilaton fields in
four dimensions.

9
The categories of this paper are: nlin
32
The categories of this paper are: atom-ph
27
The categories of this paper are: comp-gas
17
The categories of this paper are: q-fin
11
The categories of this paper are: hep-lat
34
The categories of this paper are: chem-ph
31
The categories of this paper are: ao-sci
19
The categories of this paper are: eess
16
The categories of this paper are: stat
10
The categories of this paper are: q-bio
29
The categories of this paper are: funct-an
26
The categories of this paper are: bayes-an
14
The categories of this paper are: math-ph
8
The categories of this paper are: hep-ex
3
The categories of this paper are: physics
33
The categories of this paper are: plasm-ph