We Don’t Know Everything Yet
Posted by hyperpat on November 17, 2006
Looks like yet another accomplishment for the Hubble Telescope. Analysis of some of its images of very distant supernovae is giving credence to the idea of dark energy, and that it’s been around a long time, exerting its repulsive force between objects for that entire period. Now dark energy, along with dark matter, is a pretty strange beast. The only way we can even infer its existence is the observable effect it has on the amount of gravitational force between objects. Apparently it doesn’t interact with anything else that’s ‘normal’. And yet the supposition is that over 70% of the universe is actually composed of this stuff.
One of the competing theories to explain the observed accelerating expansion of the universe is that the gravitational force is somehow changing over time. I don’t think the current observations have knocked out this hypothesis yet. And, given our poor understanding of just what gravity is, why it exists, how it propagates through ’empty’ space, and how it fits in with the strong, weak, and electromagnetic forces, (grand unified field theories have so far not been totally successful), this hypothesis appeals to me rather than the invoking of an otherwise unobservable ‘dark energy’. Of course, I’m only an engineer, not an astrophysicist, so what do I know? But at the very least, it appears that there is some method of producing a negative gravitational force. Which means that all those SF stories with anti-gravity thingies running around may not be that far off-base.