Dark Energy
When Einstein was making his historic discoveries and deductions about the nature of the our Universe, his General Theory of Relativity predicted that the combined gravitational energy of the all the matter in the Universe should be pulling everything together towards an enormous implosion, sort of like the Big Bang in reverse. But since there was no evidence that the Universe was imploding, in 1917 Einstein introduced his famous Cosmological Constant, a mathematical formula that introduced a theoretical repulsive force (for which there was no observational evidence) opposite to gravity that balanced the collective energy of the Universe, and kept it relatively stable.
Then along came Edwin Hubble in the 1920’s, who not only discovered the existence of galaxies beyond our own, but also discovered that these galaxies were in fact flying apart from each other at close to the speed of light. This directly challenged the concept of Einstein’s stable Universe, and in 1930 Einstein travelled to America to visit Hubble at the Mt. Wilson Observatory, at the time the largest telescope in the world. After viewing the receding galaxies with his own eyes, Einstein was compelled to dismiss his prediction of a stable Universe, and referred to his Cosmological Constant as the greatest blunder of my life.
Now, almost a century later, the Hubble Space Telescope has discovered that Einstein was right after all. By examining the light from 24 of the most distant supernovae known, Hubble has confirmed that 75% of our Universe is composed of a mysterious invisible force called Dark Energy that does in fact act in opposition to the forces of gravity, and is responsible for the accelerating expansion of the Universe.
With the recent mapping of invisible Dark Matter, (also courtesy of the Hubble Space Telescope), we now know with disturbing certainty that 96% of the Universe we live in contains matter that is not made of atoms, and energy that has no known source, all of which is invisible, and beyond our perception. The humbling and somewhat spooky reality is that we can only perceive 4% of the Universe around us. Coincidentally, we appear to only have conscious access to 4% of our brains as well. Coincidence, or some sort of grand cosmic plan? You tell me.