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Judging from the observed movements of distance bodies in outer space, scientists have long speculated that there is much more matter in the universe than we are aware of. The Newtonian theory of gravity predicts that galaxies will move a certain way given the gravity of their observable mass, but every time, the galaxies behave as though they contain about four times more matter than we can detect.
In 1913, a Norwegian physicist named Kristian Birkeland wrote about the possibility of unobservable matter filling up the gaps in our universe, and in 1933 a Swiss astrophysicist named Fritz Zwicky made a series of observations on a cluster of galaxies which led him to the same hypothesis. Based on Newtonian mechanics, he concluded that the galaxies must be under the influence of more gravity than that of all the detectable matter in the cluster. His observations were among the first to suggest the existence of Dark Matter.
The theory of dark matter refers to clouds of exotic particles of unknown composition that reside in the areas between stars. These theoretical particles are completely unobservable because they do not emit or reflect any appreciable amount of detectable light or radiation. They are thought to be made up of nifty-sounding subatomic bits such as neutralinos, axions, SIMPs (Strongly Interacting Massive Particles), and WIMPs (Weakly Interacting Massive Particles), however the standard model of particle physics does not recognize these exotic particles; their existence is purely hypothetical. But if the dark matter theory is true, only 4% of the of the total mass of the universe is made up of observable matter, leaving 23% for dark matter, and 73% as dark energy… an even more bizarre cousin of dark matter which has anti-gravitational properties.
In late July 2005, the initial-happy scientific colleagues F. I. Cooperstock and S. Tieu from University of Victoria made an effort to put dark matter into an early grave. They built a galaxy model which replaced I. Newton’s theory of gravity with A. Einstein’s theory of general relativity, under the notion that Newton loses his grip on interactions under those circumstances. In their model, no dark matter was necessary to explain the movements of bodies. Their theory had a nice beat and you could dance to it, but its days were numbered.
Less than a month later, a Ph. D. student at Warsaw University named Mikolaj Korzynski had exhumed the corpse of dark matter, successfully reanimated it, and sent it on a rampage. His paper showed how the model that F. I. and S. had used was physically incorrect, and described how it made some questionable assumptions. Dark matter is back, and it’s pissed. But the battle may only be beginning. Cooperstock and Tieu or a third party may yet counter-attack with a new equation-riddled paper-bomb.
For now, the theory of dark matter/dark energy is back in the realm of the scientifically feasible. Its existence would explain more than the simple gravitational anomalies, it would also account for the rate of expansion of in the universe, fill holes in the Big Bang theory, and explain how the universe’s matter became distributed the way it is today. But since dark matter is, by definition, not directly observable with current technology, its presence may be condemned to the unpredictable waiting room of science for a long time to come.