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article imageDark energy eliminates dark matter and the shape of the cosmos

By Karen Hardison     Nov 4, 2014 in Science
Dark energy, thought to be responsible for the accelerating expansion of the universe, is said to interact with dark matter destabilizing cosmic structure, evaporating dark matter and loosening the glue holding the universe's familiar shapes in place.
Dark energy was theorized to be the "cosmological constant" responsible for accelerating the speed of the expansion of the universe. New data from whole sky surveys hints that dark energy is actually not constant. It is suspected dark energy interacts with dark matter, the force that stabilizes cosmological structure. These interactions increase the amount of dark energy while decreasing the amount of dark matter. The loss of dark matter destabilizes cosmological structure causing features of the cosmos to spread apart.
In the long-run, the end result of these interactions will be a universe of myriad individual, isolated astronomical entities: Galaxies, solar systems and other complex features as we know them will be spread into discontinuity and lost: Professor David Wands of Portsmouth’s Institute of Cosmology and Gravitation: "If the dark energy is growing and dark matter is evaporating we will end up with a big, empty, boring Universe with almost nothing in it."
The problem is that data from varied "cosmological data sets" shows the expected growth of new galactic features in the cosmos — galaxies and galaxy clusters — is slower than the predicted expectation. The growth of these features is governed by dark matter, which surrounds and structures these cosmological features. Data was analyzed from such cosmological datasets as supernova type Ia, Planck cosmic microwave background, redshift space distortions and Sloan Digital Sky Survey.
Professor David Wands: "[T]he growth of cosmic structure, galaxies and clusters of galaxies, seems to be slower than expected.”
As dark matter decreases, galaxies and clusters will spin out of their shapes and structures; their "scaffolding" will be gone. As dark energy increases, its repulsive gravitational force will drive individual constituents of galactic populations farther away from each other. Over the ensuing epochs of time, the cosmos will become void of distinctive features; all will be scattered and will be repelled from all else by dark energy.
Dark Energy
It was in 1927 that Georges-Henri Lemaître suggested the idea that the universe is expanding instead of being in a static, steady state with neither expansion nor contraction occurring. In 1998, a shock came when astrophysicists Saul Perlmutter and Alex Filippenko announced the acceleration of the expanding universe.
It was theorized that a mystery force with repulsive gravity — gravity that inexplicably pushes away — was driving the acceleration of the expansion. This mystery force, invisible to the known light spectrum, was called "dark energy." It is the repulsive gravity of dark energy that will drive galactic populations away from each other once its interactions with dark matter evaporates the substance of galactic structure and generates greater quantities of negative-gravity dark energy.
Cosmological Constant
The cosmological constant was posited, then rejected by Einstein when developing his theory of general relativity. Einstein posited the universe as being static, in a steady unchanging state. To inhibit the collapse of this static universe under the force of attractive, positive gravity, Einstein added a constant factor acting against the effect of attractive (normal) gravity.
He called this the cosmological constant and envisioned it as uniformly dispersed and uniformly acting throughout the universe. He later removed the constant, then regretted having done so.
In 1998, when the force with repulsive gravity, or anti-gravity, was posited as the cause for accelerating expansion and was coined "dark energy," it was also equated with Einstein's cosmological constant: A force that has "anti-gravity" properties and resists the attractive force of massive object gravity (by Einstein's definition, the force that bends space-time in a curve around massive objects and attracts other massive objects).
Now, the cosmological constant has once again been retired because the newest data from the newest satellite and telescope research shows dark energy is, in fact, not constant but growing, increasing in quantity and, therefore, in effect. Dark energy increases because of interaction with dark matter, and therefore is not a constant cosmological factor at all.
Cosmological Data Sets
A joint team of researchers from the University of Portsmouth and the University of Rome examined cosmological datasets including (1) cosmic structure measurements taken by Sloan Digital Sky Survey; (2) microwave background temperature measurements taken by the European Space Agency Planck satellite; (3) high redshift Type Ia supernova measurements from the Supernova Cosmology Project Union2.1 data compilation from 19 datasets, including the The Hubble Space Telescope Cluster Supernova Survey; and (4) various other sources of redshift space distortion data and whole sky surveys.
The team was headed by Dr. Marco Bruni, Professor Wands, and Professor Alessandro Melchiorri who worked with research students Valentina Salvatelli and Najla Said. Their findings were published in Physical Review Letters, a journal of the American Physical Society. Their central argument is that dark energy grows through interactions with dark matter, which consequently evaporates, and the interactions seem to be slowing the growth of cosmic structure (galaxies and galaxy clusters) in the universe.
Professor Dragan Huterer of the University of Michigan, who was not connected with their research, commented that their results are consistent with the problems recent data poses when trying to fit it in the standard model of cosmology developed after the 1998 discovery of an accelerating expanding universe: "I would not say ... I am surprised at the results.... We’ve known for some months now that there is some problem in all data fitting perfectly to the standard simplest model." The standard model of cosmology posits a non-interactive dark energy that has repulsive gravity, while the data suggests an interactive dark energy.
More about Dark energy, Dark matter, Sloan digital sky survey, accelerating universe
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