Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: New tracker models of dark energy   We describe a new class of dark energy (DE) models which behave like
cosmological trackers at early times. These models are based on the
$\alpha$-attractor set of potentials, originally discussed in the context of
inflation. The new models allow the current acceleration of the universe to be
reached from a wide class of initial conditions. Prominent examples of this
class of models are the potentials $\coth\varphi$ and $\cosh\varphi$. A
remarkable feature of this new class of models is that they lead to large
enough negative values of the equation of state at the present epoch,
consistent with the observations of accelerated expansion of the universe, from
a very large initial basin of attraction. They therefore avoid the fine tuning
problem which afflicts many models of DE.

27
The categories of this paper are: comp-gas
10
The categories of this paper are: q-bio
28
The categories of this paper are: alg-geom
30
The categories of this paper are: q-alg
13
The categories of this paper are: quant-ph
4
The categories of this paper are: cond-mat
31
The categories of this paper are: ao-sci
15
The categories of this paper are: nucl-ex
36
The categories of this paper are: cmp-lg
12
The categories of this paper are: nucl-th
19
The categories of this paper are: eess
1
The categories of this paper are: cs
37
The categories of this paper are: supr-con
2
The categories of this paper are: math
32
The categories of this paper are: atom-ph
11
The categories of this paper are: hep-lat