Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Cosmological Constant and the Speed of Light   By exploring the relationship between the propagation of electromagnetic
waves in a gravitational field and the light propagation in a refractive
medium, it is shown that, in the presence of a positive cosmological constant,
the velocity of light will be smaller than its special relativity value. Then,
restricting again to the domain of validity of geometrical optics, the same
result is obtained in the context of wave optics. It is argued that this
phenomenon and the anisotropy in the velocity of light in a gravitational field
are produced by the same mechanism.

22
The categories of this paper are: chao-dyn
17
The categories of this paper are: q-fin
28
The categories of this paper are: alg-geom
31
The categories of this paper are: ao-sci
0
The categories of this paper are: hep-ph
29
The categories of this paper are: funct-an
11
The categories of this paper are: hep-lat
2
The categories of this paper are: math
35
The categories of this paper are: mtrl-th
4
The categories of this paper are: cond-mat
16
The categories of this paper are: stat
27
The categories of this paper are: comp-gas
23
The categories of this paper are: solv-int
24
The categories of this paper are: dg-ga
21
The categories of this paper are: adap-org
36
The categories of this paper are: cmp-lg