What goes up, must come down. This might seem to be a universal principle of logic, and indeed if you throw your car keys in the air, they will come crashing down to the floor on earth. But nearly a "decade ago, astronomers discovered that what is true for your car keys is not true for the galaxies. Having been impelled apart by the force of the Big Bang, the galaxies, in defiance of cosmic gravity, are picking up speed on a dash toward eternity. If they were keys, they would be shooting for the ceiling" (Overbye, 2008, p1.). According to Dennis Overbye of the New York Times on June 3, 2008, modern astronomers admit they cannot understand why this is true, or the implications for the future of the universe. Scientists call this anti-gravitational pull dark energy, as opposed to dark matter.
Overbye's article illustrates a profound, but what may be to some readers, surprising idea -- there is much that scientists still do not know about the principles at work in the universe. And they may never find an answer to the question of why dark energy exists, no matter how much time, money, effort, and technology is poured into the process by some of the finest minds in the world. True, scientists have come to a consensus upon the fact that the universe began 13.7 billion years ago with the Big Bang. The universe is made up of "4% atoms and 22% so-called dark matter of unknown identity -- perhaps elementary particles...that leaves 74% for the weight of whatever began causing the cosmos to accelerate about five billion years ago" known as dark energy (Overbye, 2008, p.1).
Before the discovery of the dark energy, quantum physicists tended to assume that the "vacuum' we live in has some deep meaning that reflects nature's deepest secrets" (Overbye, 2008, p1.). However, in 1998 astronomers discovered that the expansion of the universe was inexplicably accelerating much faster than predicted. They were studying exploding stars known as Type 1a supernovas to investigate the history and fate of the universe. "They found, on the basis of a few dozen of these stars, that the more distant ones were dimmer than expected, meaning that they had been carried farther away by the cosmic expansion than expected, meaning that the universe was speeding up" inexplicably, due to the effects of dark energy (Overbye, 2008, p.2).
Since then, scientists have used a myriad of ways to study dark energy. "They have learned how to map the growth of clusters of galaxies, by analyzing how their gravity distorts the light from galaxies far behind them," by estimating the patterns such galaxy clusters at different times in the universe's projected past and by studying sound waves from the early days of the universe (Overbye, 2008, p.3). Yet answers prove elusive. To gain more knowledge about the origins and eventual fate of the universe, a European mission known as Euclid may fly in 2017, but there may not be enough money available for the project (Overbye, 2008, p.3).
Overbye's article raises questions about the certainty of science and the ability of science to come to terms with new knowledge. Common wisdom suggests that scientists 'know' what is right but even mainstream scientists amongst may disagree with one another. Many scientists have been moved to question some of Einstein's most fundamental tenants, as a result of the discovery of dark energy. And even Einstein admitted there was a "fudge factor" or a "cosmological constant, a sort of cosmic repulsion to balance gravity and keep the universe in balance. He abandoned his constant when the universe was discovered to be expanding, but quantum physics resurrected it by showing that empty space should be foaming with energy that had the properties of Einstein's constant" (Overbye, 2008, p.1). Finally, the article exhibits how there is always a great deal of jockeying for position as to who discovered what first, and the difficulty of securing funding, particularly for something as abstract as theoretical physicists. And one unanswered question the article implicitly poses is how necessary understanding the universe is, especially in a world of scarce financial and logistical resources. Should science be more concerned with exploring how to address the needs of people on earth, instead of gazing at the stars?
Giotto and the Comet." Smashyourbrain. 30 Dec 2006. 10 Aug 2008. http://smashyourbrain.blogspot.com/2006/12/giotto-and-comet_30.html
Overbye, Dennis. "After years of effort, dark energy…