Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Evolution of shifted cosmological parameter and shifted dust matter in a
  two-phase tachyonic field universe   We propose a model of the evolution of the tachyonic scalar field over two
phases in the universe. The field components do not interact in phase I, while
in the subsequent phase II, they change flavours due to relative suppression of
the radiation contribution. In phase II, we allow them to interact mutually
with time-independent perturbation in their equations of state, as Shifted
Cosmological Parameter (SCP) and Shifted Dust Matter (SDM). We determine the
solutions of their scaling with the cosmic redshift in both phases. We further
suggest the normalized Hubble function diagnostic, which, together with the
low- and high-redshift $H(z)$ data and the concordance values of the present
density parameters from the CMBR, BAO statistics etc., constrains the strength
of interaction, by imposing the viable conditions to break degeneracy in
3-parameter $(\gamma, \varepsilon, \dot{\phi}^2)$ space. The range of redshifts
$(z=0.1$ to $z=1.75)$ is chosen to highlight the role of interaction during
structure formation, and it may lead to a future analysis of power spectrum in
this model \emph{vis a vis} Warm Dark Matter (WDM) or $\Lambda$CDM models. We
further calculate the influence of interaction in determining the age of the
universe at the present epoch, within the degeneracy space of model parameters.

1
The categories of this paper are: cs
8
The categories of this paper are: hep-ex
37
The categories of this paper are: supr-con
26
The categories of this paper are: bayes-an
23
The categories of this paper are: solv-int
34
The categories of this paper are: chem-ph
15
The categories of this paper are: nucl-ex
17
The categories of this paper are: q-fin
19
The categories of this paper are: eess
27
The categories of this paper are: comp-gas
25
The categories of this paper are: patt-sol
11
The categories of this paper are: hep-lat
4
The categories of this paper are: cond-mat
29
The categories of this paper are: funct-an
22
The categories of this paper are: chao-dyn
16
The categories of this paper are: stat