Astronomers challenge Cosmological Model

Big Bang
Time Line of the Universe. Credit: NASA/WMAP Science Team

( —Astronomers Professor Chris Collins and Dr Ian McCarthy from LJMU's Astrophysics Research Institute are challenging the view that the currently preferred cosmological model of the Universe is correct by comparing recent measurements of the cosmic background radiation and galaxy clusters in two independent studies partly funded by the Science and Technology Facilities Council.

One of the cornerstones of the Big Bang theory of the Universe is the (CBR). Discovered in 1965 these electro-magnetic waves bombard the Earth continuously from all directions at harmless microwave frequencies. However, the radiation arriving here has been cooled to only 2.7 degrees above absolute zero (as it traverses deep space) by the expansion of the universe; therefore, in the distant past the temperature would have been much higher. This leads us to the conclusion that the had a hot origin – the so called Big Bang – nearly 14 billion years ago.

The Planck Surveyor satellite, launched in 2009 by the European Space Agency (ESA), is the latest in a line of several satellites designed to measure the temperature variations in the CBR from place to place across the sky. These tiny fluctuations slowly grow over time, eventually forming the stars and galaxies we see today. Because the radiation began its journey when the Universe was only 380,000 yrs old, these measurements provide vital information about the detailed composition of our Universe. The cosmic census provided by Planck is remarkably precise, giving us amongst other things accurate estimates of: the age of the Universe (13.82 billion years) and the amount of dark matter (31.7%) and dark energy (68.3%).

It turns out that Planck is also sensitive to the largest gravitationally bound structures called clusters, which contain thousands of individual galaxies and large amounts of dark matter. Curiously, however, Planck has found fewer clusters than was predicted based on the CBR cosmological analysis.

Now, in independent studies, the recent work of both Collins and McCarthy confirms the "Planck-cluster problem" in that there are much fewer massive clusters in the Universe than expected for the Planck best-fit cosmology, a result inviting a rethink of the underlying model.

Chris Collins explains, "we already knew that the number of clusters found by the satellite was lower than expected and we have now tested this by analyzing a new carefully constructed independent survey of some 1000 clusters over a large area of the sky using X-rays rather than microwave radiation and our findings
confirm that the number of clusters is about a factor of two below the prediction based on the Planck CBR analysis."

In a separate study, Ian McCarthy, his LJMU PhD student Amandine Le Brun and collaborators examined the detailed statistical properties of the CBR and arrived at the same conclusion. McCarthy explains "we've taken a completely different approach to previous studies, by comparing the predictions of state-of-the-art supercomputer simulations with the results of sophisticated statistical analyses of the CBR. The comparison itself is quite straightforward and avoids any potential issues having to do with identifying clusters and measuring their masses."

The discrepancy in the predicted and observed number of massive clusters strongly suggests that either the detailed budgeting of the standard by Planck is not correct, or else that the model itself is flawed in some way. In the latter case, one exciting possibility is that the deficit of is pointing to an important contribution to the energy budget of the Universe by massive neutrinos, ghostly particles that interact with normal matter only very weakly. Particle physicists have long argued that neutrinos may have non-zero mass, but laboratory experiments have only managed to place relatively weak bounds on what the size of the mass is. McCarthy is planning to carry out large-scale simulations that include the effects of massive neutrinos on formation.

Collins' work is carried out in collaboration with Professor Hans Bohringer and Dr Gayoung Chon from the Max Planck Institut fur extraterrestrische Physik, Garching Germany and is to be published in Astronomy and Astrophysics.

McCarthy and Le Brun's work is carried out in collaboration with Prof. Joop Schaye from Leiden Observatory Netherlands and Dr Gilbert Holder from McGill University Montreal Canada and is to be published in Monthly Notices of the Royal Astronomical Society.

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Citation: Astronomers challenge Cosmological Model (2014, April 3) retrieved 16 September 2019 from
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Apr 03, 2014
"the age of the Universe (13.82 billion years) and the amount of dark matter (31.7%) and dark energy (68.3%)." 31.7% + 68.3% = 100%, leaving 0% normal baryonic matter I guess. Very interesting indeed!

Apr 03, 2014
'massive neutrinos'??? Quick, we need another patch! Long live the Huge Bang Fantasy!

Apr 03, 2014
Let's guess what the fudge factor used to solve this will be called. My suggestion would be 'Dark Clusters.' Presumably resulting from the interaction of dark matter with dark energy.

Apr 03, 2014
I guess with dark matter & energy composing 100% of everything........well, maybe that's why it's so difficult to figure out where we fit in, other than the possibility that humans are the true aliens.

Apr 03, 2014
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Apr 03, 2014
Hooyeeii, looks like the couyons about got this one claimed for their own. Laissez les bons temps rouler Skippys you.

Apr 04, 2014
"the age of the Universe (13.82 billion years) and the amount of dark matter (31.7%) and dark energy (68.3%)." 31.7% + 68.3% = 100%, leaving 0% normal baryonic matter I guess. Very interesting indeed!

Dark matter was supposed to be 26.8%, and baryonic matter 4.9% of total mass. Goes just a bit beyond a typo.

.....and the typo extends to the caption of their model giving the universe the appearance of a bell. Thermodynamic laws of "energy distribution" (entropy) dictate random equal distribution of all matter in relationship to one another after an explosion (big bang in this case) occurs.

This silly model shows the "Afterglow Light Pattern" at one end of the bell & none at the open end & that is not what we observe in the cosmic microwave background, we observe that as surrounding the entire universe, not secluded to one end of the bell as if the universe had been shot out of a cannon. The Universe needs to be spherical to explain the CMB in all directions.

Apr 04, 2014
Part III: Considerations on the Universe as a Whole
Albert Einstein 97
If we are to have in the universe an average density of matter which differs from zero, however small may be that difference, then the universe cannot be quasi-Euclidean. On the contrary, the results of calculation indicate that if matter be distributed uniformly, the universe would necessarily be spherical (or elliptical). Since in reality the detailed distribution of matter is not uniform, the real universe will deviate in individual parts from the spherical, i.e. the universe will be quasi-spherical. But it will be necessarily finite. In fact, the theory supplies us with a simple connection 1) between the space-expanse of the universe and the average density of matter in it.

(The above is directly from Einstein's thesis on General Relativity- There is a plethora of posters on this site who think they are at least as smart as Einstein but none of them ever saw a differential equation they could solve)

Apr 10, 2014
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Apr 10, 2014
This situation already happened with epicycle model of solar system before four hundred of years. This model had its own theory developed well, it was just terribly counterintuitive. Nobody couldn't explain, why the planets should move along epicycles in so strange way. Only few observational problems did indicate, that this model is wrong, but the astronomers of medieval era preffered to ignore it, because they made money with computing of horoscopes based on epicycle model. So that they punished and banned the Galieo for proposal of better model and another one hundred years after Galileo the epicycle model was still in use for not to threat the income, social status and qualification of existing astronomers. Those who cannot learn from history don't deserve the future.

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