Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: In Quest of a True Model of the Universe   While many observations support the validity of Einstein's general relativity
as the theory of gravity, there are yet many that suggest the presence of new
physics. In order to explain the high-redshift supernovae Ia observations
together with the recently made precise observations of the CMB anisotropy by
WMAP, the standard cosmology has to invoke some hypothetical matter with
unnatural properties which is very speculative. This casts doubts upon the
foundations of the standard cosmology and suggests that some theoretical
concept may still be missing from the theory.
  Such a concept might be the rotation of the astronomical objects, which has
not been properly taken care of when we claim that a perfect fluid is a good
approximation to the real contents of the universe. A crude estimation of the
angular kinetic energy of massive galaxies indicates to a possibility to have
$\Omega_{\rm total}\approx 1$ without invoking the hypothetical dark matter or
dark energy. This picture also appears consistent with the recent observations
of a great abundance of old massive galaxies made by Gemini Deep Deep Survey.
However, a proper relativistic theory of the rotating objects is still to be
investigated. It is expected that the consequences of incorporating rotation in
general relativity, and hence in special relativity, would be profound.

36
The categories of this paper are: cmp-lg
11
The categories of this paper are: hep-lat
37
The categories of this paper are: supr-con
14
The categories of this paper are: math-ph
15
The categories of this paper are: nucl-ex
20
The categories of this paper are: acc-phys
24
The categories of this paper are: dg-ga
33
The categories of this paper are: plasm-ph
8
The categories of this paper are: hep-ex
1
The categories of this paper are: cs
22
The categories of this paper are: chao-dyn
3
The categories of this paper are: physics
0
The categories of this paper are: hep-ph
31
The categories of this paper are: ao-sci
32
The categories of this paper are: atom-ph
16
The categories of this paper are: stat