Optics

Optics is the branch of physics which involves the behaviour and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behaviour of visible, ultraviolet, and infrared light. Because light is an electromagnetic wave, other forms of electromagnetic radiation such as X-rays, microwaves, and radio waves exhibit similar properties.

Most optical phenomena can be accounted for using the classical electromagnetic description of light. Complete electromagnetic descriptions of light are, however, often difficult to apply in practice. Practical optics is usually done using simplified models. The most common of these, geometric optics, treats light as a collection of rays that travel in straight lines and bend when they pass through or reflect from surfaces. Physical optics is a more comprehensive model of light, which includes wave effects such as diffraction and interference that cannot be accounted for in geometric optics. Historically, the ray-based model of light was developed first, followed by the wave model of light. Progress in electromagnetic theory in the 19th century led to the discovery that light waves were in fact electromagnetic radiation.

Meek Mill

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Robert Rihmeek Williams (born May 6, 1987), better known by his stage name Meek Mill, is an American hip hop recording artist from Philadelphia, Pennsylvania. He was briefly signed to Atlanta-based record label Grand Hustle, owned by record executive and fellow American rapper T.I.. In February 2011, after leaving Grand Hustle, Mill signed a record deal with fellow American rapper Rick Ross' Miami-based Maybach Music Group (MMG) imprint.

Mill's debut studio album, Dreams and Nightmares, was released in 2012, under MMG and Warner Bros. Records. The album, preceded by the single "Young & Gettin' It", debuted at number two on the U.S. Billboard 200. He has also appeared on MMG's Self Made compilation series, with his debut single "Tupac Back" and second single "Ima Boss", being included on volume one.

In October 2012, Meek Mill announced the launching of his own imprint, Dream Chasers Records, named after his popular mixtape series. He also revealed having already signed several fellow Philadelphia-based rappers in 2012.