Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Cosmological solutions with massive gravitons in the bigravity theory   We present solutions describing homogeneous and isotropic cosmologies in the
massive gravity theory with two dynamical metrics recently proposed in
arXiv:1109.3515 and claimed to be ghost free. These solutions can be spatially
open, closed, or flat, and at early times they are sourced by the perfect
fluid, while the graviton mass typically manifests itself at late times by
giving rise to a cosmological term. In addition, there are also exotic
solutions, for which already at early times, when the matter density is high,
the contribution of the graviton mass to the energy density is negative and
large enough to screen that of the matter contribution. The total energy can
then be negative, which may result in removing the initial singularity. For
special parameter values there are also solutions for which the two metrics
effectively decouple and evolve independently of each other. In the limit where
one of the gravitational coupling constant vanishes, such special solutions
reduce to those found in arXiv:1107.5504 within the theory where one of the
metrics is flat.

27
The categories of this paper are: comp-gas
29
The categories of this paper are: funct-an
8
The categories of this paper are: hep-ex
11
The categories of this paper are: hep-lat
17
The categories of this paper are: q-fin
18
The categories of this paper are: econ
15
The categories of this paper are: nucl-ex
3
The categories of this paper are: physics
10
The categories of this paper are: q-bio
22
The categories of this paper are: chao-dyn
36
The categories of this paper are: cmp-lg
9
The categories of this paper are: nlin
20
The categories of this paper are: acc-phys
37
The categories of this paper are: supr-con
16
The categories of this paper are: stat
28
The categories of this paper are: alg-geom