Documenting the Coming Singularity

Tuesday, December 19, 2006

This Ball Can Make You Feel Small

This tiny ball (about one-tenth of a millimeter in diameter), demonstrates that the universe will keep expanding forever. How so? It's really quite simple. The ball, according to Astronomy Picture of the Day,

"...moves toward a smooth plate in response to energy fluctuations in the vacuum of empty space. The attraction is known as the Casimir Effect, named for its discoverer, who, 50 years ago, was trying to understand why fluids like mayonnaise move so slowly. Today, evidence is accumulating that most of the energy density in the universe is in an unknown form dubbed dark energy. The form and genesis of dark energy is almost completely unknown, but postulated as related to vacuum fluctuations similar to the Casimir Effect but generated somehow by space itself. This vast and mysterious dark energy appears to gravitationally repel all matter and hence will likely cause the universe to expand forever. Understanding vacuum fluctuations is on the forefront of research not only to better understand our universe but also for stopping micro-mechanical machine parts from sticking together."

We've known for a few years that the universe would continue to expand, rather than reach a point of maximum expansion and then retract into a Big Crunch. Scientists discovered a force that counteracted the effects of gravity, which would have tended to pull the universe's mass back together. This expansive force they call "dark energy" because it is not well understood. As the paragraph above explains, the so-called emptiness of space is, in reality, filled with vacuum energy (another name for dark energy), with subatomic particles, called virtual particles, appearing and disappearing at random.

What does this mean for you and me? We certainly won't be around long enough to see a night sky utterly devoid of stars or galaxies (which will be a feature of the universe when matter has accelerated apart so that no light from a star can reach any other star or planet). Besides, the sun will burn the Earth to a smoking cinder long before that, anyway. (The ultimate global warming.) No, what this means for me, and perhaps for you also, is that I and my concerns are very, very insignificant in the overall scheme of things. It helps me to keep things in perspective.

How does it affect you? Comment on your thoughts if you've a mind to.