New Research Shows the Speed of Light is Variable in Real Space

Two new studies to be published in the European Physical Journal D demonstrate that the speed of light is variable in real space. Textbook explanations of the speed of light assume that light travels in a vacuum, but space is not a vacuum.

Both Marcel Urban of the University of Paris-Sud, in Orsay, France and Gerd Leuchs and Luis L. Sanchez-Soto from the Max Planck Institute for the Physics of Light in Erlangen, Germany propose that simple changes in physics theory that alter long-held concepts and present experimental proof and analysis that support the changes.

Urban and his team propose that particle pairs such as electron-positron or quark-antiquark pairs can affect the speed of light. Each photon of light would be acted upon by the transitory magnetic and electrical fields of electron-positron or quark-antiquark pairs, thus producing a small variation in the speed of light which is theoretically on the order of 50 attoseconds per square meter of crossed vacuum. The difference in speed could potentially be measured with high speed lasers.

Meanwhile, Leuchs and Sanchez-Soto propose that the impedance of a vacuum depends only on the sum of the square of the electric charge of particles, but not on their masses. Variations in the speed of light would indicate the number of charged elementary particles in a given space. The researchers have proven these results experimentally.

It is not expected that the small variation in the speed of light which has been found will affect the universally accepted theories of particle physics and quantum mechanics to a large extent, however, the studies are proof that the speed of light may be variable and shows that the mathematical treatments that have long been used should be revised to include the speed of light as variable and not a constant in real space.