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A new wiki encyclopedia project—and more! We aim at reliability and quality, not just quantity. We welcome collaboration with everyone who has knowledge, broad or narrow, about any of the world's innumerable subjects. We write under our real names—and are both collegial and congenial. We now have [[:Category:CZ Live|Template:Articles number+ articles]] and are gathering speed. Eduzendium participants write for academic credit. Write for the Citizendium—knowledge is fun! Sign up—we need both authors and editors (you might be both!) Then, get a quick start. Remember, we are an open, young project—it's easy to get involved! Wikipedians are very welcome! Learn about us Why Citizendium? For readers: About | FAQ For contributors: Authors | Editors | How to collaborate For the press Important new community pages WatchKnow will be a free, non-profit, K-12 educational video contest, currently under planning and development. Myths and Facts: Citizendium may be different from what you think! We are organizing Workgroup Weeks—our biggest initiative yet. Citizens, get involved, and watch our numbers multiply! Cleanup—helps to develop, keep and maintain a coherent structure for entries in Citizendium. Support us Our mission is educational, non-profit, global, and free. Shop at our Amazon.com and Barnes & Noble links and we'll get donations at no cost to you. Link to us so search engines can better find us.   (CC) Photo: Tanya Puntti Each sentence you add is another drop in an expanding sea of words.

Some of our finest [ about ] Approved Articles Developed Articles (over 900) "The ink of the learned is equal in merit to the blood of the martyrs." —Father Kristoforos, Birds Without Wings, by Louis de Bernières (b. 1954) Article of the Week [ about ] The ether (also spelled aether) was a concept in physics made obsolete in 1905 by Einstein's theory of special relativity. The idea of an ether was introduced into science by Descartes in Principia philosophiae (1644). Until that time, forces between two bodies that are not in direct contact were assumed to act through space—by action at a distance. Descartes replaced this explanation by one based on an intermediate medium (ether) consisting of vortices that transmit forces between bodies at a distance. The ether concept became especially predominant in the 19th century by the work of Young and Fresnel who revived Huygens' wave theory of light. They replaced Newton's light corpuscles by waves propagating through the ether. In order to explain stellar aberration, first observed in the 1720s and then shown to be caused by the velocity of the earth relative to the velocity of Newton's light corpuscles, Young (1804) assumed ether to be in a state of absolute rest. Maxwell showed in the 1860s that light waves are electromagnetic waves transverse (perpendicular) to the direction of the propagation of the waves. Following Young and Fresnel, Maxwell assumed that electromagnetic waves are vibrations of the ether. [more...] New Draft of the Week [ about ] In computer and network security, a worm is a form of malware that, once it activates inside a victim's computer, can replicate and propagate itself without further user activity. Worms often take up valuable memory and network bandwidth, which can cause a computer to stop responding, and can also allow attackers to gain unauthorized remote control of one or more computers. While the idea of a parasitic worm goes far back in biology, the term appears to have first been used as, as a concept in computing, in John Brunner's 1975 science fiction novel, Shockwave Rider. Actual software, under tightly controlled conditions, was developed in 1981-1982. [more...]