A team of Australian scientists has proposed that the speed of light may not be a constant, a revolutionary idea that could unseat one of the most cherished laws of modern physics -- Einstein"s theory of relativity.
The team, led by theoretical physicist Paul Davies of Sydney"s Macquarie University, say it is possible that the speed of light has slowed over billions of years.
If so, physicists will have to rethink many of their basic ideas about the laws of the universe.
"That means giving up the theory of relativity and E=mc squared and all that sort of stuff," Davies told Reuters.
"But of course it doesn"t mean we just throw the books in the bin, because it"s in the nature of scientific revolution that the old theories become incorporated in the new ones."
Davies, and astrophysicists Tamara Davis and Charles Lineweaver from the University of New South Wales published the proposal in the August 8 edition of scientific journal Nature.
The suggestion that the speed of light can change is based on data collected by UNSW astronomer John Webb, who posed a conundrum when he found that light from a distant quasar, a star-like object, had absorbed the wrong type of photons from interstellar clouds on its 12 billion year journey to earth.
Davies said fundamentally Webb"s observations meant that the structure of atoms emitting quasar light was slightly but ever so significantly different to the structure of atoms in humans.