- published: 19 Sep 2013
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Visible light (commonly referred to simply as light) is electromagnetic radiation that is visible to the human eye, and is responsible for the sense of sight. Visible light has a wavelength in the range of about 380 nanometres to about 740 nm – between the invisible infrared, with longer wavelengths and the invisible ultraviolet, with shorter wavelengths.
Primary properties of visible light are intensity, propagation direction, frequency or wavelength spectrum, and polarisation, while its speed in a vacuum, 299,792,458 meters per second (about 300,000 kilometers per second), is one of the fundamental constants of nature. Visible light, as with all types of electromagnetic radiation (EMR) is experimentally found to move at exactly this same speed in vacuum.
In common with all types of EMR, visible light is emitted and absorbed in tiny "packets" called photons, and 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.
David Vaughan Icke (pronounced /aɪk/, or IKE, born 29 April 1952) is an English writer and public speaker, best known for his views on what he calls "who and what is really controlling the world." Describing himself as the most controversial speaker in the world, he is the author of 19 books and has attracted a global following that cuts across the political spectrum. His 533-page The Biggest Secret (1999) has been called "the Rosetta Stone for conspiracy junkies."
Icke was a well-known BBC television sports presenter and spokesman for the Green Party, when in 1990 a psychic told him he was a healer who had been placed on Earth for a purpose, and that the spirit world was going to pass messages to him so he could educate others. In March 1991 he held a press conference to announce that he was a "Son of the Godhead" – a phrase he said later the media had misunderstood – and the following month told the BBC's Terry Wogan show that the world would soon be devastated by tidal waves and earthquakes. He said the show changed his life, turning him from a respected household name into someone who was laughed at whenever he appeared in public.
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