Speed of light is only possible to verify experimentally that the two-way speed of light (for example, from a source to a mirror and back again) is frame-independent, because it is impossible to measure the one-way speed of light (for example, from a source to a distant detector) without some convention as to how clocks at the source and at the detector should be synchronized. However, by adopting Einstein synchronization for the clocks, the one-way speed of light becomes equal to the two-way speed of light by definition. The special theory of relativity explores the consequences of this invariance of "c" with the
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,