Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Concentric circles in WMAP data may provide evidence of violent
  pre-Big-Bang activity   Conformal cyclic cosmology (CCC) posits the existence of an aeon preceding
our Big Bang 'B', whose conformal infinity 'I' is identified, conformally, with
'B', now regarded as a spacelike 3-surface. Black-hole encounters, within bound
galactic clusters in that previous aeon, would have the observable effect, in
our CMB sky, of families of concentric circles over which the temperature
variance is anomalously low, the centre of each such family representing the
point of 'I' at which the cluster converges. These centres appear as fairly
randomly distributed fixed points in our CMB sky. The analysis of Wilkinson
Microwave Background Probe's (WMAP) cosmic microwave background 7-year maps
does indeed reveal such concentric circles, of up to 6{\sigma} significance.
This is confirmed when the same analysis is applied to BOOMERanG98 data,
eliminating the possibility of an instrumental cause for the effects. These
observational predictions of CCC would not be easily explained within standard
inflationary cosmology.

11
The categories of this paper are: hep-lat
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The categories of this paper are: solv-int
24
The categories of this paper are: dg-ga
1
The categories of this paper are: cs
34
The categories of this paper are: chem-ph
10
The categories of this paper are: q-bio
21
The categories of this paper are: adap-org
18
The categories of this paper are: econ
20
The categories of this paper are: acc-phys
0
The categories of this paper are: hep-ph
7
The categories of this paper are: hep-th
25
The categories of this paper are: patt-sol
3
The categories of this paper are: physics
36
The categories of this paper are: cmp-lg
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The categories of this paper are: math-ph
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The categories of this paper are: ao-sci