Variable speed of light find out that it doesn't go only at the speed of light! It may surprise you that there is an amplitude for a photon to go at speeds faster or slower than the conventional speed, "c"." These virtual photons, however, do not violate causality or special relativity, as they are not directly observable and information cannot be transmitted acausally in the theory. Feynman diagrams and virtual photons are usually interpreted not as a physical picture of what is taking place, but rather as a convenient calculation tool (which, in some cases, happen to involve faster-than-light velocity vectors). In 1937, Paul
Light-in-flight imaging Light-in-flight imaging Light-in-flight imaging — a set of techniques to visualize propagation of light through different media. Light was first captured in its flight by N. Abramson in 1978, who used a holographic technique to record the wavefront of a pulse propagating and being scattered by a white-painted screen placed in its path. This high-speed recording technique allowed the dynamic observation of light phenomena like reflection, interference and focusing that are normally observed statically. More recently, light-in-flight holography has been performed in a scattering medium rather than using a reflective screen. Light can also be captured in motion in a