Light is electromagnetic radiation, particularly radiation of a wavelength that is visible to the human eye (about 400–700 nm, or perhaps 380–750 nm). In physics, the term light sometimes refers to electromagnetic radiation of any wavelength, whether visible or not. Four primary properties of light are: Light, which exists in tiny "packets" called photons, exhibits properties of both waves and particles. This property is referred to as the wave–particle duality. The study of light, known as optics, is an important research area in modern physics. The speed of light in a vacuum is presently defined to be exactly 299,792,458 m/s (approximately 186,282 miles per second). This definition of the speed of light means that the metre is now defined in terms of the speed of light. Light always travels at a constant speed, even between particles of a substance through which it is shining. Photons excite the adjoining particles that in turn transfer the energy to the neighbor. This may appear to slow the beam down through its trajectory in realtime. The time lost between entry and exit accounts to the displacement of energy through the substance between each particle that is

Luminosity is a measurement of brightness usually denoted in Lumens. In photometry, luminosity is sometimes incorrectly used to refer to luminance, which is the density of luminous intensity in a given direction. The SI unit for luminance is candela per square metre. In Adobe Photoshop's imaging operations, luminosity is the term used incorrectly to refer to the luma component of a color image signal; that is, a weighted sum of the nonlinear red, green, and blue signals. It seems to be calculated with the Rec. 601 luma co-efficients (Rec. 601: Luma (Y’) = 0.299 R’ + 0.587 G’ + 0.114 B’). The "L" in HSL color space is sometimes said to stand for luminosity. "L" in this case is calculated as 1/2 (MAX + MIN), where MAX and MIN refer to the highest and lowest of the R'G'B' components to be converted into HSL color space. In astronomy, luminosity is the amount of energy a body radiates per unit of time. The luminosity of stars is measured in two forms: apparent (counting visible light only) and bolometric (total radiant energy); a bolometer is an instrument that measures radiant energy over a wide band by absorption and measurement of heating. When not qualified, luminosity means

"Light" is a KMFDM single from their 1993 album Angst. The single was released in 1994 and contains nine different remixes of "Light". A. "Light" - 6:05 B. "Light (Cellulite Radio Mix)" – 3:48

Light (Japanese: ￣ﾁﾲ￣ﾁﾋ￣ﾂﾊ - Hikari) is the tenth episode of season 1 of the Air TV series originally aired 2005-03-03. TV Air 10

Light is a 2003 album by American contemporary Christian music artist Jeff Deyo.

Light is a fictional character in the long-running British science fiction television series Doctor Who.

Light was an extremely powerful, almost God-like alien being. Long ago, he took a survey of all organic life in the universe, but almost as soon as he finished 'it all started changing.' Light went into hibernation in his spaceship, hidden in the basement of Gabriel Chase. Light began to campaign against evolution and change, deciding to destroy all life so that his catalogue would never be out of date again. Before he could carry out his plan, though, the Doctor told Light that even he was changing. Unable to cope with this fact, Light 'dissipated' in the main hallway of the house.

Light is a science fiction novel written by M. John Harrison and published in 2002. It received the James Tiptree, Jr. Award and a BSFA nomination in 2002, and was shortlisted for the Arthur C. Clarke Award in 2003. The book centres on the lives of three individuals — the physicist (and serial killer) Michael Kearney, on the verge of a breakthrough in theoretical physics sometime in 1999; Seria Mau Genlicher, the cybernetically-altered female pilot of a "K-ship", and the ex-space pilot and adventurer Ed Chianese. Seria Mau and Ed's stories take place in the year 2400 AD. The lives of these three individuals are linked in many ways, though most tangibly by the presence of a mysterious creature called The Shrander, who appears in many guises to all three characters throughout the novel (with anagrammatic names of Sandra Shen and Dr. Haends). They are also linked by the Kefahuchi Tract, a space-time anomaly described as "a singularity without an event horizon", an object of awe and wonder that has been the ruin of many civilisations attempting to decode its mysteries. The Shrander takes many forms, most often with the body of an old woman in a maroon wool coat, with a horse's skull

This article is about the car. For other uses, see Automotive lighting. The Light was an automobile built in Detroit, Michigan by the Light Motor Car Company in 1914. The Light was a conventional vehicle with a six-cylinder, 30 hp engine. It came as a touring model selling for $1,250.

Light is the third album by reggae singer Matisyahu, which was released on August 25, 2009. It was anticipated since his major label debut Youth released three years before. The album has been highly successful in the reggae world, holding the top spot on the billboard reggae albums chart for over 10 non-consecutive weeks. Matisyahu had been working on his third album for nearly two years, making it the longest time he has ever spent making a record. The follow-up to Youth had been delayed several times before its release. First scheduled for early 2008, Light was pushed back numerous times because Matisyahu continued to tour off and on since the release of Youth. The new album's release date was set for April 21, 2009, but on March 3, the release date was pushed back to May 12, 2009. Then, once again, he pushed the release back, this time to Summer 2009, ostensibly because Matisyahu decided to record more new songs. That date had already passed, and in a message from Matisyahu on Twitter the album is due to release on August 25th. On May 27th, Matisyahu's FaceBook page stated that the album was going to come out on August 25th. On June 23rd Light was made available for preorder on

In theology, light or divine light is a term used to refer to an aspect of divine presence, specifically an unknown and mysterious ability of God, angels, or human beings to express themselves communicatively through spiritual means, rather than through physical capacities. In this concept, "light" can carry the full range of divine or else human-understandable concepts ranging from pure emotion up to the precise concepts and conceptualizations. Hence human beings are said to be recipients of knowledge, "truth," or "illumination," originating from God in a transcendent reality to human beings in the 'known universe,' through spiritual means. Various local religious concepts exist: Light is the core concept in Iranian mysticism. The main roots of this thought is in the Zoroastrian beliefs, which defines The supreme God Ahura Mazda as the source of light. This very essential attribute is manifested in various schools of thought in the Iranian Religions and philosophy. Latter this notion has been dispensed into the whole Middle East, having a great effect of shaping the paradigms of different religions and philosophies emerging one after another in the region. After the Arab invasion,

"Light" is the fifth episode of the first season of the science fiction television show Stargate Universe. Following from the end of "Darkness", the Destiny is on a collision course with a star. A plan is devised to use the last working shuttle to evacuate to one of the three planets. However, there is only room for seventeen people and no time for additional trips, so a lottery is held to determine who will leave.