"It's supposed to be constant!"(from physicscentral)
"It's supposed to be constant!"
Physicists measure the values of basic quantities like the speed of light and the charge of the electron. Cosmologists use the results in studies of the origin of the universe, some 12 billion years ago, and they assume the numbers have not changed over this time.
But now comes a result that could stand this assumption on its head. A research group claims that the fine structure constant, written as the Greek letter alpha (a), has increased over the last six billion years or so. Admittedly, the increase is only one part in 100,000-pretty small-but that's enough to be plenty unsettling.
Alpha specifies how strongly electromagnetic waves (like light or x-rays) affect charged particles (like electrons and protons). Alpha is actually a dimensionless ratio-all units cancel out-involving three quantities:
the charge on the electron
the speed of light
a fundamental constant from quantum mechanics
The idea that one or more of these quantities changes over time is generally most unappealing, although a few theories actually have suggested that it might happen. Since the observed effect is small, many physicists have decided to await further results before making any judgements.
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