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Einstein static Universe giti-ye istâ-ye Einstein Fr.: Univers stationnaire d'Einstein A cosmological model in which a static (neither expanding nor collapsing) Universe is maintained by introducing a cosmological repulsion force (in the form of the cosmological constant) to counterbalance the gravitational force. |
Einstein temperature damâ-ye Einstein (#) Fr.: température d'Einstein A characteristic parameter occurring in the → Einstein model of → specific heats. → Einstein; → temperature. |
Einstein tensor tânsor-e Einstein (#) Fr.: tenseur d'Einstein A mathematical entity describing the → curvature of → space-time in → Einstein's field equations, according to the theory of → general relativity. It is expressed by G_{μν} = R_{μν} - (1/2) g_{μν}R, where R_{μν} is the Ricci tensor, g_{μν} is the → metric tensor, and R the scalar curvature. This tensor is both symmetric and divergence free. Named after Albert Einstein (1879-1955); → tensor. |
Einstein time-scale marpel-e zamâni-ye Einstein Fr.: échelle de temps d'Einstein The time during which a → microlensing event occurs. It is given by the equation t_{E} = R_{E}/v, where R_{E} is the → Einstein radius, v is the magnitude of the relative transverse velocity between source and lens projected onto the lens plane. The characteristic time-scale of → microlensing events is about 25 days. → Einstein; → time-scale. |
Einstein's elevator bâlâbar-e Einstein Fr.: ascenseur d'Einstein A → thought experiment, involving an elevator, first conceived by Einstein to show the → principle of equivalence. According to this experiment, it is impossible for an observer situated inside a closed elevator to decide if the elevator is being pulled upward by a constant force or is subject to a gravitational field acting downward on a stationary elevator. Einstein used this experiment and the principle of equivalence to deduce the bending of light by the force of gravity. → einstein; elevator, from L. elevator, agent noun from p.p. stem of elevare "to lift up, raise," from → ex- "out" + levare "lighten, raise," from levis "light" in weight, → lever. Bâlâbar, → lift. |
Einstein's field equations hamugešhâ-ye meydân-e Einstein Fr.: équations de champ d'Einstein A system of ten non-linear → partial differential equations in the theory of → general relativity which relate the curvature of → space-time with the distribution of matter-energy. They have the form: G_{μν} = -κ T_{μν}, where G_{μν} is the → Einstein tensor (a function of the → metric tensor), κ is a coupling constant called the → Einstein gravitational constant, and T_{μν} is the → energy-momentum tensor. The field equations mean that the curvature of space-time is due to the distribution of mass-energy in space. A more general form of the field equations proposed by Einstein is: G_{μν} + Λg_{μν} = - κT_{μν}, where Λ is the → cosmological constant. Named after Albert Einstein (1879-1955); → field; → equation. |
Einstein's gravitational constant pâyâ-ye gerâneši-ye Einstein (#) Fr.: constante gravitationnelle d'Einstein The coupling constant appearing in → Einstein's field equations, expressed by: κ = 8πG/c^{4}, where G is the Newtonian → gravitational constant and c the → speed of light. → einstein; → gravitational; → constant. |
Einstein's theory of specific heat negare-ye garmâ-ye âbize-ye Einstein Fr.: théorie de la chaleur spécifique d'Einstein Same as → Einstein model. → Einstein; → theory; → specific heat. |
Einstein-de Sitter effect oskar-e Einstein-de Sitter Fr.: effet Einstein-de Sitter Same as → geodetic precession. |
Einstein-de Sitter Universe giti-ye Einstein-de Sitter Fr.: Univers Einstein-de Sitter The → Friedmann-Lemaitre model of → expanding Universe that only contains matter and in which space is → Euclidean (Ω_{M} > 0, Ω_{R} = 0, Ω_{Λ} = 0, k = 0). The Universe will expand at a decreasing rate for ever. → Einstein; de Sitter, after the Dutch mathematician and physicist Willem de Sitter (1872-1934) who worked out the model in 1917; → Universe. |
Einstein-Hilbert action žireš-e Einstein-Hilbert Fr.: action de Einstein-Hilbert In → general relativity, the → action
that yields → Einstein's field equations.
It is expressed by: → Einstein; → Hilbert space; → action. |
Einstein-Podolsky-Rosen paradox pârâdaxš-e Einstein-Podolsky-Rosen Fr.: paradoxe Einstein-Podolsky-Rosen → EPR paradox. A. Einstein, B. Podolsky, N. Rosen: "Can quantum-mechanical description of physical reality be considered complete?" Phys. Rev. 41, 777 (15 May 1935); → paradox. |
Einstein-Rosen bridge pol-e Einstein-Rosen Fr.: pont d'Einstein-Rosen A hypothetical structure that can join two distant regions of → space-time through a tunnel-like shortcut, as predicted by → general relativity. The Einstein-Rosen bridge is based on the → Schwarzschild solution of → Einstein's field equations. It is the simplest type of → wormholes. Albert Einstein & Nathan Rosen (1935, Phys.Rev. 48, 73); → bridge. |
Einsteinian relativity bâzânigi-ye Einsteini Fr.: relativité einsteinienne The laws of physics are the same in all → inertial reference frames and are invariant under the → Lorentz transformation. The → speed of light is a → physical constant, i.e. it is the same for all observers in uniform motion. Einsteinian relativity is prompted by the → Newton-Maxwell incompatibility. See also: → Galilean relativity, → Newtonian relativity. → Einstein; → relativity. |
einsteinium einsteinium (#) Fr.: einsteinium A radioactive metallic → transuranium element belonging to the → actinides; symbol Es. → Atomic number 99, → mass number of most stable → isotope 254 (→ half-life 270 days). Eleven isotopes are known. The element was first identified by A. Ghiorso and collaborators in the debris of first hydrogen bomb explosion in 1952. |
eject ešândan Fr.: éjecter To throw out material, for example by a massive star through stellar wind, or by a volcano in eruption. From L. ejectus, p.p. of eicere "to throw out," from → ex- "out" + -icere, comb. form of jacere "to throw." Ešândan, from Hamadâni ešândan "to throw out;" Pashto aestal, wištal "to throw, project;" Laki owštan "to throw, to shoot (with bow and arrow);" Lori šane "throwing," šane kerde "to throw;" Av. ah- "to throw," pres. ahya- "throws," asta- "thrown, shot," astar- "thrower, shooter;" cf. Khotanese ah- "to throw, shoot," Skt. as- "to throw, shoot," ásyati "throws," ásana- "throw, shot." |
ejecta ešânâk Fr.: éjecta Material, in solid, liquid, or gaseous form, thrown out by a body, especially as a result of → volcanic eruption, → meteoritic impact, or → supernova explosion. See also: → ejecta blanket, → supernova ejecta. Plural of L. ejectus, → eject. Ešânâk "that which is ejected," from šân present stem of šândan→ eject + suffix -âk. |
ejecta blanket patu-ye ešânâk Fr.: couverture d'éjecta Of an → impact crater, the ejecta that after the → impact event settles back to the Earth's surface. The ejecta blanket is thick near the → crater rim and thin outward from the crater. |
ejection ešâneš Fr.: éjection Act or instance of ejecting; the state of being ejected. Verbal noun of → eject. |
Ekman layer lâye-ye Ekman Fr.: couche d'Ekman A kind of viscous → boundary layer in a rotating fluid system. Such a layer forms over a flat bottom that exerts a frictional → stress against the flow, bringing the velocity gradually to zero within the layer above the bottom. An Ekman layer occurs also on the fluid surface whenever there is a horizontal frictional stress, for example along ocean surface, when waters are subject to wind stress. Named for Vagn Walfrid Ekman (1874-1954), Swedish oceanographer, who studied the phenomenon originally in his doctoral thesis (1902) and later developed it (1905, 1906); → layer. |
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