Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Application of Weierstrass elliptic functions to Schwarzschild Null
  Geodesics   In this paper we focus on analytical calculations involving null geodesics in
some spherically symmetric spacetimes. We use Weierstrass elliptic functions to
fully describe null geodesics in Schwarzschild spacetime and to derive
analytical formulae connecting the values of radial distance at different
points along the geodesic. We then study the properties of light triangles in
Schwarzschild spacetime and give the expansion of the deflection angle to the
second order in both $M/r_0$ and $M/b$ where $M$ is the mass of the black hole,
$r_0$ the distance of closest approach of the light ray and $b$ the impact
parameter. We also use the Weierstrass function formalism to analyze other more
exotic cases such as Reissner-Nordstr\om null geodesics and Schwarzschild null
geodesics in 4 and 6 spatial dimensions. Finally we apply Weierstrass functions
to describe the null geodesics in the Ellis wormhole spacetime and give an
analytic expansion of the deflection angle in $M/b$.

21
The categories of this paper are: adap-org
12
The categories of this paper are: nucl-th
18
The categories of this paper are: econ
32
The categories of this paper are: atom-ph
16
The categories of this paper are: stat
10
The categories of this paper are: q-bio
26
The categories of this paper are: bayes-an
29
The categories of this paper are: funct-an
20
The categories of this paper are: acc-phys
8
The categories of this paper are: hep-ex
25
The categories of this paper are: patt-sol
24
The categories of this paper are: dg-ga
11
The categories of this paper are: hep-lat
19
The categories of this paper are: eess
37
The categories of this paper are: supr-con
31
The categories of this paper are: ao-sci