Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On Five Independent Phenomena Sharing a Common Cause   Over the past century a succession of five different independent astronomical
phenomena have been discovered, each appearing to be the result of a common
underlying cause that also produces an unaccounted-for acceleration that is:
quite small, centrally directed in the system exhibiting each phenomenon,
non-gravitational, distance independent, and apparently of a common magnitude.
  The present paper analyzes the phenomena and proposes the underlying common
cause, a common solution to the problem that they present.
  Four of the phenomena, in the order of their discovery are:
  1 - In 1933, the indication by galactic rotation curves that there is such an
acceleration present and acting in galaxies but with no observable cause [hence
the postulating of "Dark Matter"]. Here the acceleration is directed toward the
galactic center, the dominant factor in the mechanics of galaxy rotation.
  2 - In 1998, the Pioneer Anomaly in which the acceleration is directed toward
the Sun, the dominant factor in the mechanics of the Pioneer spacecrafts'
motion.
  3 - In 2008, the Flybys Anomaly for which the acceleration is directed toward
the center of the Earth, the dominant factor in the mechanics of the flyby
motion [as presented in the paper following].
  4 - Also in 2008, confirmed in 2010, the Dark Flow anomaly for which the
acceleration is directed toward the central origin of the overall universe, the
dominant factor in the mechanics of the overall universe, where the Big Bang
and expansion began [as presented in the paper following].
  The earliest of all is
  5 - Hubble's discovery of Redshifts of the light from various distant astral
bodies.

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The categories of this paper are: astro-ph
25
The categories of this paper are: patt-sol
12
The categories of this paper are: nucl-th
23
The categories of this paper are: solv-int
19
The categories of this paper are: eess
10
The categories of this paper are: q-bio
1
The categories of this paper are: cs
34
The categories of this paper are: chem-ph
29
The categories of this paper are: funct-an
18
The categories of this paper are: econ
8
The categories of this paper are: hep-ex
14
The categories of this paper are: math-ph
30
The categories of this paper are: q-alg
37
The categories of this paper are: supr-con
24
The categories of this paper are: dg-ga
11
The categories of this paper are: hep-lat