Speed of light the "local" speed of light is constant and equal to "c", but the speed of light along a trajectory of finite length can differ from "c", depending on how distances and times are defined. It is generally assumed that fundamental constants such as "c" have the same value throughout spacetime, meaning that they do not depend on location and do not vary with time. However, it has been suggested in various theories that the speed of light may have changed over time. No conclusive evidence for such changes has been found, but they remain the subject of ongoing research. It
Synchrotron-Light for Experimental Science and Applications in the Middle East the current director and former vice-president of SESAME. Synchrotron light (also referred to as synchrotron radiation) is radiation that is emitted when charged particles moving at speeds near the speed of light are forced to change direction by a magnetic field. It is the brightest artificial source of X-rays, allowing for the detailed study of molecular structures. When synchrotrons were first developed, their primary purpose was to accelerate particles for the study of the nucleus. Today, there are almost 60 synchrotron light sources around the world dedicated to exploiting the special qualities, which allow it to be used across a