Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Cosmic coincidences and relic neutrinos   A simple phenomenological description for the energy transfer between a
variable cosmological constant (CC) and a gas of relic neutrinos in an
expanding universe can account for a near coincidence between the neutrino and
dark-energy densities to hold over a significant portion of the history of the
universe. Although such a cosmological setup may promote neutrinos to
mass-varying particles, both with slow and quick neutrino mass changing with
the expansion of the universe naturally implemented in the model, it also works
equally well for static neutrino masses. We also stress what sort of models for
variable CC can potentially underpin the above scenario.

21
The categories of this paper are: adap-org
12
The categories of this paper are: nucl-th
10
The categories of this paper are: q-bio
20
The categories of this paper are: acc-phys
30
The categories of this paper are: q-alg
13
The categories of this paper are: quant-ph
25
The categories of this paper are: patt-sol
9
The categories of this paper are: nlin
19
The categories of this paper are: eess
18
The categories of this paper are: econ
35
The categories of this paper are: mtrl-th
0
The categories of this paper are: hep-ph
27
The categories of this paper are: comp-gas
31
The categories of this paper are: ao-sci
32
The categories of this paper are: atom-ph
11
The categories of this paper are: hep-lat