Under the Copernican cosmological principle, there can be no special locations, directions, or observers of our universe- no up, no down, no left, no right, no center, no edges.
This principle is the absolutely indispensable assumption that must be true in order for standard cosmology - the Big Bang story we tell ourselves about the cosmos and our place in it - to be true. Instead, beginning with the Axis of Evil and now including similarly anti-Copernican Principle alignments with the ecliptic and equinoxes of Earth involving quasars, galaxies, distributions of Supernovae, and other phenomena, the observations are telling us that the Copernican Principle is wrong, and that earth seems to occupy a special, even a central, position with respect to the largest visible structures in the universe.
It is difficult to overstate the implications here.
Obviously, if science has had it wrong for five hundred years in its fundamental, basic assumption about the universe and our position and significance in it, then we face one of those watershed moments in history where the entirety of the human family’s view of itself and of the universe is about to change. In such a case it is about to change in ways that are emphatically reminiscent of the ancient Catholic cosmology, where earth was the center and focus of the entire creation, precisely because it was the place of the Incarnation of the Son of God.
The stakes could not possibly be any higher.
So now seems as good a time as any to look at the other possibility. What if these observations are not actually cosmological phenomena after all? Could they be the result of some systematic error in our observations? Could they result from some local foreground that is distorting the data received by our sensors from the furthest reaches of the universe?
Amazingly, we are down to a simple either/or with the entirety of the Big Bang creation story.
Either the Copernican Principle, and therefore the Big Bang cosmology that has shaped all of our lives stands observationally falsified, or the data have been contaminated in completely unknown ways, by some foreground or systematic error that has affected essentially every large scale cosmology survey of the last several decades.
Door Number One, or Door Number Two.
I will refer to this paper yet again: a 2016 study by Wen Zhao and Larissa Santos, “Preferred axis in cosmology�, states the problem succinctly:
The foundation of modern cosmology relies on the so-called cosmological principle which states an homogeneous and isotropic distribution of matter in the universe on large scales. However, recent observations, such as the temperature anisotropy of the cosmic microwave background (CMB) radiation, the motion of galaxies in the universe, the polarization of quasars and the acceleration of the cosmic expansion, indicate preferred directions in the sky. If these directions have a cosmological origin, the cosmological principle would be violated, and modern cosmology should be reconsidered.
That would be Door Number One.
Next, Zhao and Santos tell us about Door Number Two:
…the coincidence (note: along the kinematic dipole, assumed to be the result of our motion through the CMB) of all these preferred directions hints that these anomalies have a common origin, which is not cosmological or due to a gravitational effect. The systematical or contaminative errors in observation or in data analysis, which can be directly related to the motion of our local group of galaxies, can play an important role in explaining the anomalies.
And there it is.
If one assumes that the CMB dipole is the result of our motion with respect to the so-called CMB rest frame - the CMB is redshifted in the opposite direction of our motion, blueshifted in the direction of our motion- then it becomes almost irresistible to notice all of these other phenomena lining up along the same direction, and assume that something must be contaminating the data, making it look like we are the center.
Now this is a very familiar argument to those who have seen “The Principle“, since it has essentially been the argument against every evidence of a geocentric universe since the time Edward Hubble first looked through his telescope and noticed that galaxies appeared to be flying away from us in all directions, making us the center of the universe.
As Lawrence Krauss says in the opening montage of “The Principle�:
It always seems like we’re the center of the universe. But we’re not.
The first sentence above correctly reports the experimental and observational history of cosmology, while the second reports the foundational assumption - dogma, for some - of the Copernican enterprise.
Door Number Two involves a number of serious difficulties, the first of which is that it requires us to reject what we have seen- the alignments- in favor of what we haven’t– the unknown foreground or systematic error.
But that is often done in cosmology when observations contradict what is deeply believed to be well-established theory.
Dark matter is a classic example.
We have known for going on seventy years that spiral galaxies do not spin according to the Newton and Einstein laws of gravity.
Either those laws stand observationally falsified…or else there must be a huge amount of matter we cannot see, which we can then add in where needed in order to bridge the otherwise-insuperable gap between theory and observation.
So - since the Copernican Principle is even more fundamental to standard cosmology than is the present theory of gravity – it ought not surprise us too much that leading theorists are quite prepared to proceed on the assumption that the theory is most likely to be right, and therefore the observations are most likely to be wrong- Lawrence Krauss proposes exactly that in “The Principle� by the way.
But, as Max Tegmark memorably puts it, during his second interview near the end of “The Principle“, as much as his “gut� was telling him there had to be “something fishy� in the data suggesting an alignment with the CMB and the ecliptic, he had to use his brain to override his gut.
He had to accept the reality of the alignments in the data after the Planck mission confirmed them in 2013.
And there exists another fundamental problem for Door Number Two:
In order for the observations to all line up along the CMB kinematic dipole (and hence with the ecliptic and equinoxes of earth), that dipole ought to actually be the result of our motion.
It ought to match up with dipoles at other cosmological scales- in galaxies and quasars, for instance.
We would expect to see a dipole- redshift in one direction, blueshift in another- when we measured these other objects as well, to verify and confirm that the CMB dipole is in fact measuring our motion.
However, as the following excerpts from Ashok Singal’s 2011 and 2013 papers, animated in the “New Science� special feature, show- unless the earth has moved at three drastically different velocities in two opposite directions (!) during various epochs of cosmological expansion- we cannot rely upon the very thing Zhao says is “well known�- that the CMB dipole is the result of our motion!
First, Singal reports in 2011:
We determine the peculiar velocity of the solar system relative to the frame of distant radio sources, by studying the anisotropy in the sky brightness from discrete radio sources, i.e., an integrated emission from discrete sources per unit solid angle. Our results give a direction of the velocity vector in agreement with the Cosmic Microwave Background Radiation (CMBR) value, but the magnitude (∼ 1600 ± 400 km/s) is ∼ 4 times the CMBR value (369 ± 1 km/s) at a statistically significant (∼ 3σ) level.
So, if the CMB dipole measures our motion, why does the radio sky dipole measure our motion along the same direction, but four times faster?
But wait.
There’s more.
Singal published another paper in 2014, reporting an “Extremely large peculiar motion of the solar system detected using redshift distribution of distant quasars“.
https://arxiv.org/pdf/1405.4796.pdf
And this one is the killer:
We determine the peculiar velocity of the solar system relative to the frame of distant quasars, by studying the dipole anisotropy, if any, in the redshift distribution of a large sample of quasars distributed across the sky. The magnitude of the peculiar velocity thus determined turns out be extremely large (9750 ± 550 km/s; ∼ 3% the speed of light), and is about an order of magnitude larger than the velocity determined from the dipole anisotropy in the Cosmic Microwave Background Radiation or the value determined earlier relative to the frame of distant radio sources.
Oops.
Now we have Earth moving at three different velocities, one of them an order of magnitude higher than the other two!
And just to top it off with a maraschino cherry:
Even the direction of the motion is in a direction nearly opposite to the earlier determinations.
So now we have Earth moving at three different velocities in two opposite directions, if we assume that these dipoles actually measure our motion!
The large differences in the magnitudes of inferred motion as well as their opposite signs are rather disconcerting. A genuine difference between these velocity vectors would imply highly anisotropic Universe, with anisotropy changing with epoch. This would violate the cosmological principle where the isotropy of the Universe is assumed for all epochs, and which is the basis of modern cosmological models.
“Rather disconcerting� indeed.
In closing, a brief aside and insight into how peer review can affect the progress of science.
Here is a link to Singal’s paper from 2013:
https://arxiv.org/abs/1305.4134
Notice the title:
“Is There a Violation of the Copernican Principle in the Radio Sky?�
Notice, at the top, that a new version has replaced it, dated 2014:
https://arxiv.org/abs/1305.4134v1
The new title says nothing about the Copernican Principle.
I have it on good authority, from a scientist who is in correspondence with Singal, that the title change was part of an effort on Singal’s part to overcome resistance to having his paper published by a peer reviewed astrophysics journal.
Anyway.
The 2013 abstract is stunning, assigning a 99.995% probability that the observed distribution of radio galaxies and quasars about a plane passing through the two equinoxes and the north celestial pole (!) is a violation of the Copernican cosmological principle:
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…Two pertinent questions then arise. First, why should there anisotropies 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…
The 2014 updated abstract, while less of an eye-grabber in terms of its title, is even more breathtaking in its results:
If we include all the observed asymmetries in the sky distributions of quasars and radio galaxies in the 3CRR sample, the probability of their occurrence by a chance combination reduces to ∼2×10−5.
That would be:
A 0.00002% chance.
99.99998% likely to be a violation of the Copernican cosmological principle.
Feeling lucky?
For these and other reasons, I have my money on Door Number One:
In the next five to ten years, the Copernican Principle will be abandoned, and therefore, standard cosmology along with it.
We will closely follow developments, as it is perfectly good science for all possibilities to be exhaustively considered and tested.
After all…
It’s not every day that humanity’s entire picture of the universe and its own place and significance in it stands on the verge of being turned upside down.
