Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: $f(R)$ gravity constrained by PPN parameters and stochastic background
  of gravitational waves   We analyze seven different viable $f(R)$-gravities towards the Solar System
tests and stochastic gravitational waves background. The aim is to achieve
experimental bounds for the theory at local and cosmological scales in order to
select models capable of addressing the accelerating cosmological expansion
without cosmological constant but evading the weak field constraints. Beside
large scale structure and galactic dynamics, these bounds can be considered
complimentary in order to select self-consistent theories of gravity working at
the infrared limit. It is demonstrated that seven viable $f(R)$-gravities under
consideration not only satisfy the local tests, but additionally, pass the
above PPN-and stochastic gravitational waves bounds for large classes of
parameters.

23
The categories of this paper are: solv-int
20
The categories of this paper are: acc-phys
26
The categories of this paper are: bayes-an
13
The categories of this paper are: quant-ph
17
The categories of this paper are: q-fin
35
The categories of this paper are: mtrl-th
33
The categories of this paper are: plasm-ph
30
The categories of this paper are: q-alg
34
The categories of this paper are: chem-ph
4
The categories of this paper are: cond-mat
21
The categories of this paper are: adap-org
32
The categories of this paper are: atom-ph
37
The categories of this paper are: supr-con
15
The categories of this paper are: nucl-ex
31
The categories of this paper are: ao-sci
14
The categories of this paper are: math-ph