Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Radial infall of two compact objects: 2.5PN linear momentum flux and
  associated recoil   The loss rate of linear momentum from a binary system composed of compact
objects (radially falling towards each other under mutual gravitational
influence) has been investigated using the multipolar post-Minkowskian
approach. The 2.5PN accurate analytical formula for the linear momentum flux is
provided, in terms of the separation of the two objects, in harmonic
coordinates, both for a finite and infinite initial separation. The 2.5PN
formulas for the linear momentum flux are finally used to estimate the recoil
velocity accumulated during a premerger phase of the binary evolution.

27
The categories of this paper are: comp-gas
37
The categories of this paper are: supr-con
23
The categories of this paper are: solv-int
17
The categories of this paper are: q-fin
22
The categories of this paper are: chao-dyn
21
The categories of this paper are: adap-org
36
The categories of this paper are: cmp-lg
1
The categories of this paper are: cs
3
The categories of this paper are: physics
31
The categories of this paper are: ao-sci
33
The categories of this paper are: plasm-ph
26
The categories of this paper are: bayes-an
35
The categories of this paper are: mtrl-th
4
The categories of this paper are: cond-mat
29
The categories of this paper are: funct-an
30
The categories of this paper are: q-alg