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Thermodynamics

Thermodynamics
Annotated color version of the original 1824 Carnot heat engine showing the hot body (boiler), working body (system, steam), and cold body (water), the letters labeled according to the stopping points in Carnot cycle Thermodynamics applies to a wide variety of topics in science and engineering. Historically, thermodynamics developed out of a desire to increase the efficiency and power output of early steam engines, particularly through the work of French physicist Nicolas Léonard Sadi Carnot (1824) who believed that the efficiency of heat engines was the key that could help France win the Napoleonic Wars.[1] Irish-born British physicist Lord Kelvin was the first to formulate a concise definition of thermodynamics in 1854:[2] "Thermo-dynamics is the subject of the relation of heat to forces acting between contiguous parts of bodies, and the relation of heat to electrical agency." Introduction[edit] A thermodynamic system can be defined in terms of its states. History[edit] Etymology[edit] Related:  Wikipedia

Magic satchel In role-playing video games, a magic satchel is a character's inventory in the game. The magic satchel can often contain more (or larger) items than should be physically possible for the character to carry. The concept is so common in fantasy fiction that it is parodied by the character The Luggage in the Discworld series. Similar concepts[edit] The term hammerspace describes the seemingly invisible place from which fictional characters, such as cartoon characters, pull out very large objects, such as mallets. Technically the term hammerspace is not used to refer to a magic satchel itself, but rather the area or pocket of space that a magic satchel occupies; a magic satchel is like a door to hammerspace. The "bag of holding" is a similar concept in the role-playing game Dungeons & Dragons. A real-world example is the clown car which often is used in the circus, in which numerous clowns clamber out of a tiny automobile. Origin[edit] Characteristics in video games[edit] Examples[edit]

Plutocracy Plutocracy (from Greek πλοῦτος, ploutos, meaning "wealth", and κράτος, kratos, meaning "power, dominion, rule") or plutarchy, is a form of oligarchy and defines a society or a system ruled and dominated by the small minority of the wealthiest citizens. The first known use of the term was in 1652.[1] Unlike systems such as democracy, capitalism, socialism or anarchism, plutocracy is not rooted in an established political philosophy. The concept of plutocracy may be advocated by the wealthy classes of a society in an indirect or surreptitious fashion, though the term itself is almost always used in a pejorative sense.[2] Usage[edit] Examples[edit] Examples of plutocracies include the Roman Empire, some city-states in Ancient Greece, the civilization of Carthage, the Italian city-states/merchant republics of Venice, Florence, Genoa, and pre-World War II Empire of Japan (the zaibatsu). Modern politics[edit] United States[edit] Post World War II[edit] Russia[edit] As a propaganda term[edit]

Michelson–Morley experiment Figure 1. Michelson and Morley's interferometric setup, mounted on a stone slab and floating in a pool of mercury. The Michelson–Morley experiment was published in 1887 by Albert A. Michelson–Morley type experiments have been repeated many times with steadily increasing sensitivity. Detecting the aether[edit] Physics theories of the late 19th century assumed that just as surface water waves must have a supporting substance, i.e. a "medium", to move across (in this case water), and audible sound requires a medium to transmit its wave motions (such as air or water), so light must also require a medium, the "luminiferous aether", to transmit its wave motions. Figure 2. According to this hypothesis, Earth and the aether are in relative motion, implying that a so-called "aether wind" (Fig. 2) should exist. 1881 and 1887 experiments[edit] Michelson experiment (1881)[edit] Figure 3. Michelson had a solution to the problem of how to construct a device sufficiently accurate to detect aether flow.

QED vacuum The quantum electrodynamic vacuum or QED vacuum is the field-theoretic vacuum of quantum electrodynamics. It is the lowest energy state (the ground state) of the electromagnetic field when the fields are quantized.[1] When Planck's constant is hypothetically allowed to approach zero, QED vacuum is converted to classical vacuum, which is to say, the vacuum of classical electromagnetism.[2][3] Another field-theoretic vacuum is the QCD vacuum of the Standard Model. Fluctuations[edit] The QED vacuum is subject to fluctuations about a dormant zero average-field condition:[4] Here is a description of the quantum vacuum:[5] “The quantum theory asserts that a vacuum, even the most perfect vacuum devoid of any matter, is not really empty. Virtual particles[edit] It is sometimes attempted to provide an intuitive picture of virtual particles based upon the Heisenberg energy-time uncertainty principle: Quantization of the fields[edit] Electromagnetic properties[edit] Attainability[edit] References[edit]

Tim Berners-Lee Sir Timothy John "Tim" Berners-Lee, OM, KBE, FRS, FREng, FRSA, DFBCS (born 8 June 1955),[1] also known as TimBL, is an English computer scientist, best known as the inventor of the World Wide Web. He made a proposal for an information management system in March 1989,[2] and he implemented the first successful communication between a Hypertext Transfer Protocol (HTTP) client and server via the Internet sometime around mid-November of that same year.[3][4][5][6][7] Berners-Lee is the director of the World Wide Web Consortium (W3C), which oversees the Web's continued development. He is also the founder of the World Wide Web Foundation, and is a senior researcher and holder of the Founders Chair at the MIT Computer Science and Artificial Intelligence Laboratory (CSAIL).[8] He is a director of the Web Science Research Initiative (WSRI),[9] and a member of the advisory board of the MIT Center for Collective Intelligence.[10][11] Early life Career Current work Awards and honours Personal life

Van Allen radiation belt This video illustrates changes in the shape and intensity of a cross section of the Van Allen belts Van Allen radiation belts (cross section) A radiation belt is a layer of energetic charged particles that is held in place around a magnetized planet, such as the Earth, by the planet's magnetic field. The Earth has two such belts and sometimes others may be temporarily created. Discovery[edit] Kristian Birkeland, Carl Størmer, and Nicholas Christofilos had investigated the possibility of trapped charged particles before the Space Age.[3] Explorer 1 and Explorer 3 confirmed the existence of the belt in early 1958 under James Van Allen at the University of Iowa. Research[edit] Jupiter's variable radiation belts The NASA Van Allen Probes mission will go further and gain scientific understanding (to the point of predictability) of how populations of relativistic electrons and ions in space form or change in response to changes in solar activity and the solar wind. Outer belt[edit] Causes[edit]

Barrett Brown He has spent over a year in FCI Seagoville federal prison and at one time faced over a hundred more as he awaited trial on an assortment of seventeen charges filed in three indictments that include sharing an HTTP link to information publicly released during the 2012 Stratfor email leak, and several counts of conspiring to publicize restricted information about an FBI agent.[3][4][5][6] Between September 2013 and April 2014 he was held under an agreed gag order prohibiting him from discussing his case with the media.[3][7] Early life and education[edit] He attended the private Episcopal School of Dallas for high school but dropped out after his sophomore year. Journalism[edit] Brown co-wrote the book Flock of Dodos: Behind Modern Creationism, Intelligent Design and the Easter Bunny, a comic critique of intelligent design and creationism.[10] In 2010, Brown began work on his crowdsourced investigation wiki, Project PM. On the aim of Project PM, Brown has stated: Arrest and trial[edit]

Windhexe Windhexe is a grinding and dehydrating apparatus operated with compressed air typically used in waste reduction and food processing. The Windhexe was unveiled in 2002 and operates via compressed air injected into a conical chamber which tumbles material at high speeds causing simultaneous dehydration and disintegration. The limited application of the Windhexe is in waste reduction and in animal processing with more proposed uses being explored commercially. History[edit] The Windhexe was invented by retired Kansas farmer Frank Polifka. Following retirement Polifka began work on the Windhexe which was completed despite Polifka having only completed a secondary education.[1] The Windhexe was unveiled to a small group of the local press in 2002, following 15 years of work by Polifka. Description[edit] The Windhexe operates using heated pressurized air. Compressed air is injected at the top through nozzles. Applications[edit] Waste reduction[edit] Animal processing[edit] References[edit]

The Zeitgeist Movement The Zeitgeist Movement advocates a transition from a global money-based economic system to their version of a resource-based economy.[2] The informal group was founded by and is directed by Peter Joseph.[2] Joseph's films, form the basis of The Zeitgeist Movement's ideas. The films are critical of market capitalism and the price system method in general. Joseph created a political movement according to The Daily Telegraph, that dismisses historic religious concepts as misleading and embraces a version of sustainable ecological concepts and science administration of society.[3] The name of the group comes from the German word Zeitgeist, meaning "spirit of the age" or "spirit of the time". History[edit] Views[edit] Currently[edit] The Zeitgeist Movement's ideas are presented through local and national chapters and online release of media.[2] Zeitgeist holds an annual event, Z-Day, in March. Reception[edit] See also[edit] References[edit] External links[edit] Official website

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