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Saturday, June 4, 2011

What Lies Beyond the Observable Hubble Universe?


Few theories qualify for Nobel laureate Niels Bohr's famous question more than the current Big Bang Theory of the origin of the Universe: "We are all agreed that your theory is crazy. The question that divides us is whether it is crazy enough to have a chance of being correct."
There is a growing body of data and theory which question whether the Universe may have begun with a Big Bang 13.75 billion years ago. Several leading cosmologists, such as Sean Carroll of CalTech and Neil Turok of Cambridge University challenge the prevailing model of a "Big Bang" and believe that in the future we will only look back in wonder at how anyone could have believed in a creation event which was refuted by so much evidence. 



The origin of the Big Bang (that is, the state of "existence" which resulted in a Big Bang) is a mathematically obscure state --- a "singularity" of zero volume that contained infinite density and infinite energy. Why this singularity existed, how it originated, and why it exploded has led many scientists to question and challenge the very foundations of the Big Bang theory. 
It has been pointed out that an accelerated expansion limited to the most distant regions of the known universe, is incompatible with an explosive origin, but instead is indicative of an attractive force --- a "universe-in-mass" black hole whose super-gravity is affecting red shifts and illumination --- creating the illusion of a universe which is accelerating as it speeds away, when instead the stars closest to the hole are speeding faster toward their doom. Other scientists observe that the interpretation of red shifts as supporting a Big Bang, is also flawed and lacking validity. Some experts believe that there is little evidence to support the belief that red shifts are accurate measures of distance or time; that they are so variable and affected by so many factors that estimates of age, time, and distance can vary by up to 3 billion years following repeated measurements of the same star over just a few years.

Although the "Big Bang" is often presented as if it is proven fact, there is a wealth of data, including recent revelations of the several space probes and findings in fundamental physics, which possibly tell a different story.

One of the first problems are found in the Large Scale Structures in the Universe. In recent years, there have been a number of very serious challenges to the current theory of cosmic evolution and the belief the universe began just 13.7 billion years ago. The existence of these "Superclusters", "Great Walls" and "Great Attractors" could have only come to be organized and situated in their present locations and to have achieved their current size in a universe which is at least 80 billion to 250 billion years in age. The largest superclusters --- for example, the  "Coma" --- extend up to 100 Mpc!

In 1986, Brent Tully of the University of Hawaii reported detecting superclusters of galaxies 300 million light years (mly) long and 100 mly thick - stretching out about 300 mly across. At the speeds at which galaxies are supposed to be moving, it would require 80 billlion years to create such a huge complex of galaxies.

In 1989 a group led by John Huchra and Margaret J. Geller at the Harvard-Smithsonian Center for Astrophysics discovered "The Great Wall", a series of galaxies lined up and creating a "wall" of galaxies 500 million light years (mly) long, 200 mly wide, and 15 mly thick. This superstructure would have required at least 100 billion years to form.

A team of the British, American, and Hungarian astronomers have reported even larger structures. As per their findings, the universe is crossed by at least 13 'Great Walls', apparent rivers of galaxies 100Mpc long in the surveyed domain of 7 billion light years. They found galaxies clustered into bands spaced about 600 million light years apart. The pattern of these clusters stretches across about one-fourth of the diameter of the universe, or about seven billion light years. This huge shell and void pattern would have required nearly 150 billion years to form, based on their speed of movement, if produced by the standard Big Bang cosmology.

Sloane_9, The "Sloan Great Wall" of galaxies as detected by the Sloan Digital Survey, has earned the distinction of being the largest observed structure in the Universe. It is 1.36 billion light years long and 80% longer than the Great Wall discovered by Geller and Huchra. It runs roughly from the head of Hydra to the feet of Virgo. It would have taken at least 250 billion years to form.

Then there is the problem of gravity. "Hubble length" Universe, which consists of those galaxies and stars which can be observed by current technology, appears, therefore, to be organized as titanic walls and clusters of galaxies separated by a collection of giant bubble-like voids. The Great Walls are far too large and massive to have been formed by the mutual gravitational attraction of its member galaxies alone.

Based on the cosmological principle, which is one of the cornerstones of the Big Bang model, cosmologists predicted the distribution of matter to be homogeneous throughout the universe, implying thereby that the distribution of the galaxies would be essentially uniform. There would be no large scale clusters of galaxies or great voids in space. Instead, contrary to the "Big Bang" universe, we exist in a very "lumpy" cosmos.

Many of the world's leading physicists believe we are entering  a "golden age" of cosmological discoveries. Astronomers working on the WMAP mission stunned the scientific community with their announcement that the first generation stars in the universe were surprisingly born just after 200 million years of the Big Bang birth of the cosmos. The age of the universe has been steadily pushed backwards in time, from 2 billion year to 8 billion after it was determined the Earth was 4.6 billion years in age, and now the estimates are 13.75 billion years.

The James Webb Space Telescope (JWST), successor to the HST with ten times the light-gathering power due to be launched in 2014, may well detect ever more distant galaxies. Likewise, the ultra-high resolution radio telescopes such as Atacama Large Millimeter Array (ALMA) in Chile which is to become operational in 2012, will be peering still deeper into the universe, and probably pushing the hypothetical Big Bang further backward in time as ever more distant galaxies are detected.

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