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adaptive radiation

(Encyclopedia)CE5 Adaptive radiation in Hawaiian honey-creepers adaptive radiation, in biology, the evolution of an ancestral species, which was adapted to a particular way of life, into many diverse species, e...

Cherenkov radiation

(Encyclopedia)Cherenkov radiation or Cerenkov radiation [for P. A. Cherenkov], light emitted by a transparent medium when charged particles pass through it at a speed greater than the speed of light in the medium. ...

radiation chemistry

(Encyclopedia)radiation chemistry: see radiochemistry. ...

Van Allen radiation belts

(Encyclopedia)CE5 Van Allen radiation belts: The solar wind, a stream of protons, electrons, and ions coming from the sun, gives the belts their asymmetrical shape. Van Allen radiation belts, belts of radiation...

angstrom

(Encyclopedia)angstrom ăngˈstrəm [key], abbr. Å, unit of length equal to 10−10 meter (0.0000000001 meter); it is used to measure the wavelengths of visible light and of other forms of electromagnetic radiatio...

electrodynamics

(Encyclopedia)electrodynamics, study of phenomena associated with charged bodies in motion and varying electric and magnetic fields (see charge; electricity); since a moving charge produces a magnetic field, electr...

Poynting, John Henry

(Encyclopedia)Poynting, John Henry, 1852–1914, British physicist. He was educated at Liverpool and Cambridge and was professor of physics at the Univ. of Birmingham for most of his life. He is best known for the ...

ether, in physics and astronomy

(Encyclopedia)ether or aether, in physics and astronomy, a hypothetical medium for transmitting light and heat (radiation), filling all unoccupied space; it is also called luminiferous ether. In Newtonian physics a...

Maxwell, James Clerk

(Encyclopedia)Maxwell, James Clerk klärk [key], 1831–79, great Scottish physicist. After a brilliant career at Edinburgh and Cambridge, where he won early recognition with mathematical papers, he was a professor...

light

(Encyclopedia)light, visible electromagnetic radiation. Of the entire electromagnetic spectrum, the human eye is sensitive to only a tiny part, the part that is called light. The wavelengths of visible light range ...