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Antigravity
Anti-gravity (also known as non-gravitational field) is a hypothetical phenomenon of creating a place or object that is free from the force of gravity. It does not refer to the lack of weight under gravity experienced in free fall or orbit, or to balancing the force of gravity with some other force, such as electromagnetism or aerodynamic lift. Anti-gravity is a recurring concept in science fiction. Examples are the gravity blocking substance "Cavorite" in H. G. Wells's ''The First Men in the Moon'' and the Spindizzy machines in James Blish's ''Cities in Flight''. "Anti-gravity" is often used to refer to devices that look as if they reverse gravity even though they operate through other means, such as lifters, which fly in the air by moving air with electromagnetic fields. Historical attempts at understanding gravity The possibility of creating anti-gravity depends upon a complete understanding and description of gravity and its interactions with other physical theories, such ...
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The First Men In The Moon
''The First Men in the Moon'' is a scientific romance by the English author H. G. Wells, originally serialised in ''The Strand Magazine'' from December 1900 to August 1901 and published in hardcover in 1901, who called it one of his "fantastic stories". The novel tells the story of a journey to the Moon undertaken by the two protagonists: a businessman narrator, Mr. Bedford; and an eccentric scientist, Mr. Cavor. Bedford and Cavor discover that the Moon is inhabited by a sophisticated extraterrestrial life, extraterrestrial civilisation of insect-like creatures they call "Selenites". The inspiration seems to come from the famous 1870 book by Jules Verne, ''From the Earth to the Moon'', and Le voyage dans la lune (opera-féerie), the opera by Jacques Offenbach from 1875. In that opera the word "selenites" is used for the first time for moon inhabitants. Plot summary The narrator is a London businessman named Bedford who withdraws to the countryside to write a play, by which he ...
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Ionocraft
An ion-propelled aircraft or ionocraft is an aircraft that uses electrohydrodynamics (EHD) to provide lift or thrust in the air without requiring combustion or moving parts. Current designs do not produce sufficient thrust for manned flight or useful loads. History Origins The principle of ionic wind propulsion with corona-generated charged particles was discovered soon after the discovery of electricity with references dating to 1709 in a book titled ''Physico-Mechanical Experiments on Various Subjects'' by Francis Hauksbee. VTOL "lifter" experiments American experimenter Thomas Townsend Brown spent much of his life working on the principle, under the mistaken impression that it was an anti-gravity effect, which he named the Biefeld–Brown effect. Since his devices produced thrust in the direction of the field gradient, regardless of the direction of gravity, and did not work in a vacuum, other workers realized that the effect was due to EHD. VTOL ion-propelled aircraft are s ...
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Albert Einstein
Albert Einstein ( ; ; 14 March 1879 – 18 April 1955) was a German-born theoretical physicist, widely acknowledged to be one of the greatest and most influential physicists of all time. Einstein is best known for developing the theory of relativity, but he also made important contributions to the development of the theory of quantum mechanics. Relativity and quantum mechanics are the two pillars of modern physics. His mass–energy equivalence formula , which arises from relativity theory, has been dubbed "the world's most famous equation". His work is also known for its influence on the philosophy of science. He received the 1921 Nobel Prize in Physics "for his services to theoretical physics, and especially for his discovery of the law of the photoelectric effect", a pivotal step in the development of quantum theory. His intellectual achievements and originality resulted in "Einstein" becoming synonymous with "genius". In 1905, a year sometimes described as his ' ...
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Graviton
In theories of quantum gravity, the graviton is the hypothetical quantum of gravity, an elementary particle that mediates the force of gravitational interaction. There is no complete quantum field theory of gravitons due to an outstanding mathematical problem with renormalization in general relativity. In string theory, believed by some to be a consistent theory of quantum gravity, the graviton is a massless state of a fundamental string. If it exists, the graviton is expected to be massless because the gravitational force has a very long range, and appears to propagate at the speed of light. The graviton must be a spin-2 boson because the source of gravitation is the stress–energy tensor, a second-order tensor (compared with electromagnetism's spin-1 photon, the source of which is the four-current, a first-order tensor). Additionally, it can be shown that any massless spin-2 field would give rise to a force indistinguishable from gravitation, because a massless spin-2 field ...
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Christie's
Christie's is a British auction house founded in 1766 by James Christie (auctioneer), James Christie. Its main premises are on King Street, St James's in London, at Rockefeller Center in New York City and at Alexandra House in Hong Kong. It is owned by Groupe Artémis, the holding company of François-Henri Pinault. Sales in 2015 totalled £4.8 billion (US$7.4 billion). In 2017, the ''Salvator Mundi (Leonardo), Salvator Mundi'' was sold for $400 million at Christie's in New York, at the time List of most expensive paintings, the highest price ever paid for a single painting at an auction. History Founding The official company literature states that founder James Christie (auctioneer), James Christie (1730–1803) conducted the first sale in London, England, on 5 December 1766, and the earliest auction catalogue the company retains is from December 1766. However, other sources note that James Christie rented auction rooms from 1762, and newspaper advertisements for Christi ...
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Quantum Field Theory
In theoretical physics, quantum field theory (QFT) is a theoretical framework that combines classical field theory, special relativity, and quantum mechanics. QFT is used in particle physics to construct physical models of subatomic particles and in condensed matter physics to construct models of quasiparticles. QFT treats particles as excited states (also called Quantum, quanta) of their underlying quantum field (physics), fields, which are more fundamental than the particles. The equation of motion of the particle is determined by minimization of the Lagrangian, a functional of fields associated with the particle. Interactions between particles are described by interaction terms in the Lagrangian (field theory), Lagrangian involving their corresponding quantum fields. Each interaction can be visually represented by Feynman diagrams according to perturbation theory (quantum mechanics), perturbation theory in quantum mechanics. History Quantum field theory emerged from the wo ...
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James Clerk Maxwell
James Clerk Maxwell (13 June 1831 – 5 November 1879) was a Scottish mathematician and scientist responsible for the classical theory of electromagnetic radiation, which was the first theory to describe electricity, magnetism and light as different manifestations of the same phenomenon. Maxwell's equations for electromagnetism have been called the " second great unification in physics" where the first one had been realised by Isaac Newton. With the publication of "A Dynamical Theory of the Electromagnetic Field" in 1865, Maxwell demonstrated that electric and magnetic fields travel through space as waves moving at the speed of light. He proposed that light is an undulation in the same medium that is the cause of electric and magnetic phenomena. (This article accompanied an 8 December 1864 presentation by Maxwell to the Royal Society. His statement that "light and magnetism are affections of the same substance" is at page 499.) The unification of light and electrical ...
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Theodor Kaluza
Theodor Franz Eduard Kaluza (; 9 November 1885 – 19 January 1954) was a German mathematician and physicist known for the Kaluza–Klein theory, involving field equations in five-dimensional space-time. His idea that fundamental forces can be unified by introducing additional dimensions re-emerged much later in string theory. Life Kaluza was born to a Roman Catholic family from the town of Ratibor (present-day Racibórz in Poland) in the German Empire's Prussian Province of Silesia. Kaluza himself was born in Wilhelmsthal (a village that was incorporated into Oppeln (present-day Opole) in 1899). He spent his youth in Königsberg, where his father, Max Kaluza, was a professor of the English language. He entered the University of Königsberg to study mathematics and gained his doctorate with a thesis on Tschirnhaus transformations. Kaluza was primarily a mathematician but began studying relativity. In April 1919 Kaluza noticed that when he solved Albert Einstein's equations ...
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Electromagnetism
In physics, electromagnetism is an interaction that occurs between particles with electric charge. It is the second-strongest of the four fundamental interactions, after the strong force, and it is the dominant force in the interactions of atoms and molecules. Electromagnetism can be thought of as a combination of electricity and magnetism, two distinct but closely intertwined phenomena. In essence, electric forces occur between any two charged particles, causing an attraction between particles with opposite charges and repulsion between particles with the same charge, while magnetism is an interaction that occurs exclusively between ''moving'' charged particles. These two effects combine to create electromagnetic fields in the vicinity of charge particles, which can exert influence on other particles via the Lorentz force. At high energy, the weak force and electromagnetic force are unified as a single electroweak force. The electromagnetic force is responsible for many o ...
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General Theory Of Relativity
General relativity, also known as the general theory of relativity and Einstein's theory of gravity, is the differential geometry, geometric scientific theory, theory of gravitation published by Albert Einstein in 1915 and is the current description of gravitation in modern physics. General theory of relativity, relativity generalizes special relativity and refines Newton's law of universal gravitation, providing a unified description of gravity as a geometric property of space and time in physics, time or four-dimensional space, four-dimensional spacetime. In particular, the ' is directly related to the energy and momentum of whatever matter and radiation are present. The relation is specified by the Einstein field equations, a system of second order partial differential equations. Newton's law of universal gravitation, which describes classical gravity, can be seen as a prediction of general relativity for the almost flat spacetime geometry around stationary mass distribution ...
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Walther Mayer
Walther Mayer (11 March 1887 – 10 September 1948) was an Austrian mathematician, born in Graz, Austria-Hungary. With Leopold Vietoris he is the namesake of the Mayer–Vietoris sequence in topology.. He served as an assistant to Albert Einstein,. and was nicknamed "Einstein's calculator". Biography Mayer studied at the Federal Institute of Technology in Zürich and the University of Paris before receiving his doctorate in 1912 from the University of Vienna; his thesis concerned the Fredholm integral equation.. He served in the military between 1914 and 1919, during which he found time to complete a habilitation on differential geometry. Because he was Jewish, he had little opportunity for an academic career in Austria, and left the country; however, in 1926, with help from Einstein, he returned to a position at the University of Vienna as Privatdozent (lecturer). He made a name for himself in topology with the Mayer–Vietoris sequence, and with an axiomatic treatment of homolog ...
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