Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Comments on Unified dark energy and dark matter from a scalar field
  different from quintessence   In a recent paper by C. Gao, M. Kunz, A. Liddle and D. Parkinson
[arXiv:0912.0949], the unification of dark matter and dark energy was explored
within a theory containing a scalar field of non-Lagrangian type. This scalar
field, different from the classic quintessence, can be obtained from the scalar
field representation of an interacting two-fluid mixture described in the paper
by L.P. Chimento and M. Forte [arXiv:0706.4142]

19
The categories of this paper are: eess
10
The categories of this paper are: q-bio
14
The categories of this paper are: math-ph
33
The categories of this paper are: plasm-ph
22
The categories of this paper are: chao-dyn
24
The categories of this paper are: dg-ga
26
The categories of this paper are: bayes-an
9
The categories of this paper are: nlin
31
The categories of this paper are: ao-sci
30
The categories of this paper are: q-alg
23
The categories of this paper are: solv-int
37
The categories of this paper are: supr-con
1
The categories of this paper are: cs
18
The categories of this paper are: econ
32
The categories of this paper are: atom-ph
8
The categories of this paper are: hep-ex