group velocity of light
71Speed of sound — Sound is a vibration that travels through an elastic medium as a wave. The speed of sound describes how much distance such a wave travels in a certain amount of time. In SI Units with dry air at 20 °C (68 °F), the speed of sound is 343 m/s. This… …
72colour — /kul euhr/, n., adj. v.t., v.i. Chiefly Brit. color. Usage. See or1. * * * I Aspect of any object that may be described in terms of hue, brightness, and saturation. It is associated with the visible wavelengths of electromagnetic radiation, which …
73Modulational instability — In the field of nonlinear optics, modulational instability is a phenomenon whereby deviations from an optical waveform are reinforced by nonlinearity, leading to the generation of spectral sidebands and the eventual breakup of the waveform into a …
74Eastern epistemology — Jain EpistemologyAccording to Jain epistemology, reality is multifaceted ( anekanta , or non one sided ), such that no finite set of statements can capture the entire truth about the objects they describe. The Jain list of pramanas (valid sources …
75The Dark Energy Survey — DES logo The Dark Energy Survey (DES) is a survey that aims to probe the dynamics of the expansion of the universe and the growth of large scale structure. The collaboration is composed of research institutes and universities from United… …
76Defining equation (physics) — For common nomenclature of base quantities used in this article, see Physical quantity. For 4 vector modifications used in relativity, see Four vector. Very often defining equations are in the form of a constitutive equation, since parameters of… …
77Graphene — is a one atom thick planar sheet of sp2 bonded carbon atoms that are densely packed in a honeycomb crystal lattice. It can be viewed as an atomic scale chicken wire made of carbon atoms and their bonds. The name comes from GRAPHITE + ENE;… …
78Celeritas — Die Geschwindigkeit von Licht im Vakuum, die Vakuum Lichtgeschwindigkeit c (von lat. celeritas: „Schnelligkeit“), ist in der Relativitätstheorie die höchste Geschwindigkeit, mit der sich eine Ursache auswirken kann. Dies stimmt mit allen… …
79Langsames Licht — Die Geschwindigkeit von Licht im Vakuum, die Vakuum Lichtgeschwindigkeit c (von lat. celeritas: „Schnelligkeit“), ist in der Relativitätstheorie die höchste Geschwindigkeit, mit der sich eine Ursache auswirken kann. Dies stimmt mit allen… …
80Lichtbremsung — Die Geschwindigkeit von Licht im Vakuum, die Vakuum Lichtgeschwindigkeit c (von lat. celeritas: „Schnelligkeit“), ist in der Relativitätstheorie die höchste Geschwindigkeit, mit der sich eine Ursache auswirken kann. Dies stimmt mit allen… …
