To some, Dark Energy sounds too much like science fiction, rather than being one of the most exciting and significant discoveries of all time. Such implications could substantially change everything, from quantum physics, gravitation, and even cosmology.
There is so much that we are only just beginning to understand, or still have yet to discover about the infinite expanse of outer space. Once, before the conceptualization of theories like Dark Energy, space remains as elusive as the celestial bodies that embodies its farthest reaches.
What is Dark Energy?
There is much conjecture regarding dark energy, since there is still less known then there actually is known about it. The term actually came fully about in the early 1990’s, when a bunch of scientist began researching the changes in the density of the universe. Essentially, it became conclusive that there was evidence of rapid expansion witnessed, but it still had no conclusive explanation. So, they all decidedly chose to name this progression: Dark Energy.
A Scientific Approach:
Now, to fully understand the nature of Dark Energy, one must consider space as somehow being comprised of various elements, both physical and hypothetical. Thanks to several competing scientific groups; the Supernova Cosmology Project and the High-Z Supernova Search team, whom are dedicated to observing such cataclysmic events, such as when a dense-class star explodes, dubbed a Type Ia Supernovae. Using some of the most sophisticated land-based observation equipment, such as NASA’s Hubble Space Telescope (HST), and the Chandra X-ray Observatory; they were able to see first-hand that we truly live in a expanding universe.
Since 1998, independent studies using NASA’s equipment, alongside the complex Wilkinson Microwave Anisotropy Probe (WMAP), they concluded that approximately 72% of the universe’s density was comprised of Dark Energy, leaving a measly 4.6% to Atoms, and the remaining 23% to Dark Matter (Another article).
This being said, there are still other ideologies that either counter or coincide with Dark Energy theories, which I have summarized below:
Based upon the laws of both Sir Isaac Newton and Albert Einstein, such as Einstein’s cosmological constant, which was a modification to his original theory of relativity. This was later dismissed after observation of the Hubble redshift, indicating that the universe was likely not stationary. This would mean a new law of gravity to explain why cosmic expansion is accelerating.
Dynamic Energy Fields:
Another theory suggests that an invisible energy field exists, known as quintessence permeates our universe. However, the nature of this field is in constant transition, which for the moment quintessence is causing cosmic acceleration
Energy of Empty Space:
This last, and more widely accepted theory has already merit; since for the last few decades, it was understood that even empty space contained some form of energy. Although, space being a vacuum, this would be the value known as the true cosmological constant. Meaning the energy would be responsible for stretching the galaxy apart at a increasing rate.
So, whether it’s just a Jedi mind trick, or a tangible form of subatomic particle yet to be measured; Dark Energy is still on the minds of many. One such venture, the Joint Dark Energy Mission (JDEM), developed by NASA and the Office of High Energy Physics at the U.S. Department of Energy; believe they can precisely measure the universe’s expansion rate, and how this rate has changed over time.
There are more complexities to this topic, but this is as much theory as it is fact. Once again, to boldly go where no man has gone before, the final frontier is quickly coming into focus, and maybe soon we will know all the mysteries to behold about Dark Energy.