“Physical quantities such as the speed of light, the gravitational constant and the electron mass are believed to be the same independent of where and when they appear in the universe. Therefore, they are known as constants of nature.”
The article linked below reports that there is evidence which indicates that the fine structure constant is changing over time. This corroborates a report back in April that the proton/electron mass ratio has changed over time as well.
Thus there is reason to believe that the laws of physics are changing over time. This will probably necessitate a rethinking of the present dark-matter and dark-energy models. It also would seem to violate the Cosmological Principle which tacitly assumes that physical laws are unchanging – and the much more fundamental Copernican Principle as well.
Just goes to show how little we actually do understand about the Universe.
(Via Physics Org.)