The Speed Of Light

3 Pages 847 Words

Using the world's largest telescope, the 30-foot-wide Keck Telescope in Hawaii, a team of experimentalists led by John Webb of the University of New South Wales in Sydney, Australia, observed patterns of light absorption in the gas clouds that could not be explained without assuming a change in a basic constant of nature called the fine structure constant. The fine structure constant is a combination of three other universal constants: electric charge, light speed, and Planck's constant, named for the German physicist Max Planck. Planck's constant is important in the study of atoms and subatomic particles.



Because the speed of light is an integral part of the fine structure constant, the research of John Moffat, plus that of John Barrow, Andreas Albrecht, and Joao Magueijo, has become the theoretical centerpiece of what could be one of the most stunning and revolutionary scientific discoveries ever -- that light did not always travel at a constant speed.



Moffat, a physicist at the University of Toronto, first proposed a variable speed of light as a way to explain certain cosmological puzzles, such as why the universe has uniform temperatures and densities.



Known as the "horizon problem," this universal uniformity is hard to explain if light has forever traveled at the same constant speed. Light carries the energy that would smooth out the many density and temperature variations that must have arisen after the Big Bang. The universe is simply too big for constant-speed light signals to have had time to travel throughout, smoothing out all the lumps -- that is, unless light traveled much faster in the early universe than it does today.



"It is immediately obvious that if the speed of light were larger in the past one could resolve the horizon problem of the universe, " Demos Kazanas, a physicist with the Goddard Space Flight Center in Greenbelt, Md., told United Press International.



Moffat published his i...