Shedding light on the nature of light

THE report about a team of scientists from Glasgow showing that the speed of light is not a constant as many of us assume made waves in the news recently. That discovery is even more important since one of the main co-authors is Dr. Jacqueline Romero who is a Filipina who graduated from the University of the Philippines in Diliman. Their experiment clarified that once we go beyond the simple picture of light being uniform in amplitude like a sheet as it moves in space and time (called a plane wave), we cannot anymore assume that the speed of light will be a constant.

Why is this relevant? The paper itself points out that our understanding of the world holds that “the speed of light in free space propagation is a fundamental quantity.” This means that this constant that we use applies only to this strict subset of light of plane waves. If one would measure the speed of light for other cases, then there would a difference especially if there is structure imposed on the light beam thorough the apertures that it passes through as well as the kind of medium that it has gone through.