Variable speed of light with Einstein and stated both speed and direction of light change in a gravity field first published 1923 in English, 1920 in German. Born expressed the magnitude of light speed as the square root of (−"g"/"g") gravity components in general relativity to leave no doubt about his intent. Richard Tolman also agreed with Einstein and expressed the radial speed of light as "dr"/"dt" in a gravity field. where "m" is "MG"/"c" and where natural units are used such that "c" is equal to one. Robert Dicke, in 1957, developed a related VSL theory of gravity. In contrast to Einstein, Dicke
Max Planck Institute for the Science of Light Planck Society. In June 2008, after an evaluation, the senate of the Max Planck Society decided to convert this group to a Max Planck institute and thereupon founded the "Max Planck Institute for the Science of Light" (German "Max-Planck-Institut für die Physik des Lichts"). with effect from January 1, 2009. In 2016, the new building was opened. The project was made by the Munich architecture bureau "Fritsch + Tschaidse Architekten GmbH". 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,