More on the Fine Structure Constant
Bonker writes "Neat news from the Beeb. It turns out that data collected from observation of quasars indicates that the fine structure constant of the universe, aka 'Alpha', may have changed since the universe began. It may have been very slightly smaller than it is right now. The article hints that other constants we're familiar with, such as high, holy 'c', may also vary over time. Of course values can't have changed dramatically, because that would mean that low-weight atoms such as carbon would be unstable, and without carbon, there wouldn't be anyone around to measure the fine structure constant anyway." We ran a story about this last year. It looks like the team has continued to check their work for errors and hasn't found any yet.
alpha is the coupling constant for the electromagnetic force.
In other words, it determines the "strengh" of the electromagnetic force. It is important because
a) it has no units (it's just a number, approximately 1/137)
b) it is easy to measure to a great degree of accuracy
c) it can be measured using a variety of different experiments
d) many fundamental phyiscal constants (such as c - the speed of light in a vacuum, e - the charge of an electron, and h - the Planck constant.
So a change in alpha would mean a change in one of the fundamental constants of physics.
For more information, you can read NIST's wonderful description.
"You have the option of insanity. I do not. And that makes me crazy!" - Brian to Angela, My So-Called Life