Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A new insight into the negative-mass paradox of gravity and the
  accelerating universe   The discovery of acceleration of the universe expansion in recent
astrophysics research prompts the author to propose that the Newton's
gravitation law can be generalized to accommodate the antimatter: While the
force between matters(antimatters) is attractive, the force between matter and
antimatter is a repulsive one. A paradox of negative-mass in gravity versus a
basic symmetry (m-->-m) based on quantum mechanics is discussed in sufficient
detail so that the new postulate could be established quite naturally.
Corresponding modification of the theory of general relativity is also
suggested. If we believe in the symmetry of particle and antiparticle as well
as the antigravity between them, it might be possible to consider a new
scenario of the expansion of universe which might provide some new insight into
the interpretation of cosmological phenomena including the accelerating
universe observed.

0
The categories of this paper are: hep-ph
21
The categories of this paper are: adap-org
33
The categories of this paper are: plasm-ph
17
The categories of this paper are: q-fin
30
The categories of this paper are: q-alg
32
The categories of this paper are: atom-ph
25
The categories of this paper are: patt-sol
37
The categories of this paper are: supr-con
12
The categories of this paper are: nucl-th
36
The categories of this paper are: cmp-lg
7
The categories of this paper are: hep-th
8
The categories of this paper are: hep-ex
9
The categories of this paper are: nlin
34
The categories of this paper are: chem-ph
5
The categories of this paper are: gr-qc
15
The categories of this paper are: nucl-ex