Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: An effective theory of accelerated expansion   We work out an effective theory of accelerated expansion to describe general
phenomena of inflation and acceleration (dark energy) in the Universe. Our aim
is to determine from theoretical grounds, in a physically-motivated and model
independent way, which and how many (free) parameters are needed to broadly
capture the physics of a theory describing cosmic acceleration. Our goal is to
make as much as possible transparent the physical interpretation of the
parameters describing the expansion. We show that, at leading order, there are
five independent parameters, of which one can be constrained via general
relativity tests. The other four parameters need to be determined by observing
and measuring the cosmic expansion rate only, H(z). Therefore we suggest that
future cosmology surveys focus on obtaining an accurate as possible measurement
of $H(z)$ to constrain the nature of accelerated expansion (dark energy and/or
inflation).

8
The categories of this paper are: hep-ex
10
The categories of this paper are: q-bio
20
The categories of this paper are: acc-phys
33
The categories of this paper are: plasm-ph
17
The categories of this paper are: q-fin
24
The categories of this paper are: dg-ga
3
The categories of this paper are: physics
29
The categories of this paper are: funct-an
9
The categories of this paper are: nlin
23
The categories of this paper are: solv-int
4
The categories of this paper are: cond-mat
5
The categories of this paper are: gr-qc
37
The categories of this paper are: supr-con
13
The categories of this paper are: quant-ph
27
The categories of this paper are: comp-gas
26
The categories of this paper are: bayes-an