Electromagnetic radiation Electromagnetic radiation In physics, electromagnetic radiation (EM radiation or EMR) refers to the waves (or their quanta, photons) of the electromagnetic field, propagating (radiating) through space, carrying electromagnetic radiant energy. It includes radio waves, microwaves, infrared, (visible) light, ultraviolet, X-rays, and gamma rays. Classically, electromagnetic radiation consists of electromagnetic waves, which are synchronized oscillations of electric and magnetic fields that propagate at the speed of light, which, in a vacuum, is commonly denoted "c". In homogeneous, isotropic media, the oscillations of the two fields are perpendicular to each other and perpendicular to the direction of energy and wave propagation, forming
Levitin effect Levitin effect The Levitin effect refers to the phenomenon, first documented by Dr. Daniel J. Levitin in 1994, that people – even those without musical training – tend to remember songs in the correct key. The finding stood in contrast to the large body of laboratory literature suggesting that such details of perceptual experience are lost during the process of memory encoding. In other words, laboratory experiments supported the idea that most people are incapable of any sort of absolute pitch, and thus would remember melodies with relative pitch. Despite its status as a classic result in cognitive psychology, the