Variable speed of light Variable speed of light A variable speed of light (VSL) is a feature of a family of hypotheses stating that the speed of light in vacuum, usually denoted by "c", may in some way not be constant, e.g. varying in space or time, or depending on frequency. A variable speed of light occurs in some situations of classical physics as equivalent formulations of accepted theories, but also in various alternative theories of gravitation and cosmology, many of them non-mainstream. Notable attempts to incorporate a variable speed of light into physics have been made by Einstein in 1911, by Robert Dicke
Max Planck Institute for the Science of Light Max Planck Institute for the Science of Light The Max Planck Institute for the Science of Light (MPL) performs basic research in optical metrology, optical communication, new optical materials, plasmonics and nanophotonics and optical applications in biology and medicine. It is part of the Max Planck Society and was founded on January 1, 2009 in Erlangen near Nuremberg. The Institute is based on the Max Planck Research Group "Optics, Information and Photonics", which was founded in 2004 at the University of Erlangen-Nuremberg, as a precursor. The institute currently comprises five divisions. The institute currently is organized in five divisions, each