Another new paper, just posted today:
"Is there a violation of the Copernican principle in the radio sky"?
This one is highly interesting, since it is based not on any new observations from Planck, but instead on an entirely unrelated statistical analysis of one of the oldest and most widely used catalogues of radio sources.
The paper shows that the data has been staring us in the face for decades!
It was in the process of looking at the data in a new way that the astonishing result "falls out":
arXiv:1305.4134v1 [astro-ph.CO] 17 May 2013
"Here we report even larger anisotropies in the sky distributions
of powerful extended quasars and some other sub-classes of radio galaxies in
the 3CRR catalogue, one of the oldest and most intensively studies sample of
strong radio sources5,6,7. The anisotropies lie about a plane passing through
the two equinoxes and the north celestial pole (NCP). We can rule out at a
99.995% confidence level the hypothesis that these asymmetries are merely due
to statistical fluctuations. Further, even the distribution of observed radio sizes
of quasars and radio galaxies show large systematic differences between these
two sky regions. The redshift distribution appear to be very similar in both
regions of sky for all sources, which rules out any local effects to be the cause
of these anomalies. Two pertinent questions then arise. First, why should there
be such large anisotropies present in the sky distribution of some of the most
distant discrete sources implying inhomogeneities in the universe at very large
scales (covering a fraction of the universe)? What is intriguing even further
is why such anisotropies should lie about a great circle decided purely by the
orientation of earth’s rotation axis and/or the axis of its revolution around the
sun? It looks as if these axes have a preferential placement in the larger scheme
of things, implying an apparent breakdown of the Copernican principle or its
more generalization, cosmological principle, upon which all modern cosmological
theories are based upon.
"Copernican principle states that earth does not have any eminent or privileged position
in the universe and therefore an observer’s choice of origin and/or orientation of his/her
coordinate system should have no bearing on the appearance of the distant universe. Its
natural generalization is the cosmological principle that the universe on a sufficiently large
scale should appear homogeneous and isotropic, with no preferred directions, to all observers. However to us on earth the universe does show heterogeneous structures up to
the scale of superclusters of galaxies and somewhat beyond, but it is assumed that it will
all appear homogeneous and isotropic when observed on still larger scales, perhaps beyond
a couple of hundreds of megaparsecs. Radio galaxies and quasars, the most distant dis-
crete objects (at distances of many gigaparsecs or further) seen in the universe should trace
the distribution of matter in the universe at that large scale and should therefore appear
isotropically distributed from any vantage point in the universe including that on earth.
One of the earliest and best studied source of radio galaxies and quasars is the 3CRR (3rd
Cambridge twice revised) catalogue5,6,7, which is radio complete in the sense that all ra-
dio sources brighter than a certain sensitive limit are included and also it has complete
optical identification content with detailed optical spectra to classify radio sources in to
radio galaxies and quasars. The catalogue with the latest updates is downloadable from
https://www.astrosci.ca/users/willottc/3crr/3crr.html.
The last sentence of his article reads: "But irrespective of that
ReplyDeletethere is no denying that from the large anisotropies present in the
radio sky, independently seen both in the discrete source distribution and in the diffuse CMBR, the Copernican principle seems to be in jeopardy." Oh, my what a beautiful understatement!