Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Observable acceleration of jets by a Kerr black hole   In the framework of a model based on the gravitational field of the Kerr
black hole, we turn to investigate the kinematic behavior of extragalactic
jets. We analytically calculate the observable velocities and accelerations
along any geodesic. Then, by numerical calculations, we apply our results to a
geodesic, typical of the M87 jet, and probe our results by confrontation to
recent observations. A transition from non-relativistic to ultrarelativistic
speeds at subparsec scale is highlighted. This transition comes sooner and more
abruptly than in models based on magnetic paradigm, which indicates that we
need a weaker magnetic field to explain observed synchrotron radiation. We
attribute the ejection phenomenon to the repulsive effect of the
gravitomagnetic Kerr field.

15
The categories of this paper are: nucl-ex
16
The categories of this paper are: stat
37
The categories of this paper are: supr-con
36
The categories of this paper are: cmp-lg
9
The categories of this paper are: nlin
28
The categories of this paper are: alg-geom
14
The categories of this paper are: math-ph
0
The categories of this paper are: hep-ph
12
The categories of this paper are: nucl-th
27
The categories of this paper are: comp-gas
1
The categories of this paper are: cs
10
The categories of this paper are: q-bio
26
The categories of this paper are: bayes-an
19
The categories of this paper are: eess
25
The categories of this paper are: patt-sol
7
The categories of this paper are: hep-th