<< < -ge Gal gal Gal gam gas Gau gen gen geo geo geo gia glo gol gra gra gra gra gre gri gui > >>
gas-rich galaxy kahkešân-e porgâz Fr.: galaxie riche en gaz A galaxy, usually young, which has a relatively important gas content. |
gas-to-dust ratio vâbar-e gâz bé qobâr Fr.: rapport gaz/poussière The mass ratio of gas to dust. It amounts to approximately 100 in the → interstellar medium, but may vary in → molecular clouds and → circumstellar disks due to dust → grain evaporation, → dust settling, → condensation of gas, etc. The gas-to-dust ratio depends on the → metallicity. It is larger in galaxies with lower metallicity. |
gaseous gâzi (#) Fr.: gazeux 1) Existing in the → state of a gas. |
gaseous diffusion paxš-e gâzi Fr.: diffusion gazeuse An → isotope separation process using the different diffusion speeds of → atoms or → molecules for separation. This process is used to divide → uranium hexafluoride (UF_{6}) into two separate streams of U-235 and U-238. Before processing by gaseous diffusion, uranium is first converted from → uranium oxide (U_{3}O_{8}) to UF_{6}. The UF_{6} is heated and converted from a solid to a gas. The gas is then forced through a series of compressors and converters that contain porous barriers. Because uranium-235 has a slightly lighter isotopic mass than uranium-238, UF_{6} molecules made with uranium-235 diffuse through the barriers at a slightly higher rate than the molecules containing uranium-238. At the end of the process, there are two UF_{6} streams, with one stream having a higher concentration of uranium-235 than the other (EVS, a Division of Argonne National Laboratory). |
gaseous nebula miq-e gâzi Fr.: nébuleuse gazeuse An → H II region, a → planetary nebula, or a → supernova remnant. |
gauge (n.) gaz; (v.) gaz kardan Fr.: jauge 1) (n.) A standard of measure or measurement, size, or quantity. From Fr. jauge "gauging rod," perhaps from Frankish galga "rod, pole for measuring;" cf. O.N. gelgja "pole, perch;" O.H.G. galgo; Lith. zalga "pole, perch;" Arm. dzalk "pole;" E. gallows; see below. Gaz "a yard for measuring cloth; a length of 24 finger-breadths, or six hands; the tamarisk-tree," from Mid.Pers. gaz "tamarisk," may be of the same origin as gauge. In verbal form with kardan "to do, to make" (Mid.Pers. kardan; O.Pers./Av. kar- "to do, make, build;" Av. kərənaoiti "he makes;" cf. Skt. kr- "to do, to make," krnoti "he makes, he does," karoti "he makes, he does," karma "act, deed;" PIE base k^{w}er- "to do, to make"). |
gauge boson bozon-e gaz Fr.: boson de jauge A class of elementary particles that includes the gluon, photon, W^{+}, W^{-}, and Z^{0} particles, each having an integral spin. |
gauge group goruh-e gaz (#) Fr.: groupe de jauge The mathematical group associated with a particular set of gauge transformations. |
gauge invariance nâvartâyi-ye gaz Fr.: invariance de jauge The invariance of any field theory under gauge transformation. → gauge; → invariance. |
gauge symmetry hamâmuni-ye gaz Fr.: symétrie de jauge A principle underlying the quantum-mechanical description of the three non-gravitational forces. It allows a system to behave in the same way even though it has undergone various transformations. The earliest physical theory which had a gauge symmetry was Maxwell's electrodynamics. |
gauge theory negare-ye gaz (#) Fr.: théorie de jauge A field theory in which it is possible to perform a transformation without altering any measurable physical quantity. |
gauge transformation tarâdis-e gaz (#) Fr.: transformation de jauge A change of the fields of a gauge theory that does not change the value of any measurable quantity. → gauge; → transformation. |
gauging gazkard Fr.: A technique in which the thickness, density, or quantity of a material is determined by the amount of radiation it absorbs. Gauging, from → gauge + → -ing, suffix of nouns formed from verbs, expressing the action of the verb or its result. Gazkard, from gaz, → gauge, + kard past stem of kardan "to do, make," → gauge. |
Gaunt factor karvand-e Gaunt Fr.: facteur de Gaunt In the atomic theory of spectral line formation, a quantum mechanical correction factor applied to the absorption coefficient in the transition of an electron from a bound or free state to a free state. Gaunt, after John Arthur Gaunt (1904-1944), English physicist born in China, who significantly contributed to the calculation of continuous absorption using quantum mechanics; → factor |
gauss gauss (#) Fr.: gauss The c.s.g. unit of magnetic flux density (or magnetic induction), equal to 1 maxwell per square centimeter, or 10^{-4} tesla. Named after the German mathematician and physicist Carl Friedrich Gauss (1777-1855). |
Gauss's law for electricity qânun-e Gauss dar barq Fr.: loi de Gauss en électricité The total electric flux ψ out of an arbitrary closed surface in free space is equal to the net charge within the surface divided by the → permittivity. In differential form: ∇ . E = ρ/ε_{0}, where ρ is the → charge density and ε_{0} the permittivity. The integral form of the law: ∫E . dS = Q/ε_{0} (closed surface integral). This is one of the four → Maxwell's equations. → gauss; → law; → electricity. |
Gauss's law for magnetism qânun-e Gauss dar meqnâtmandi Fr.: loi de Gauss en magnétisme The → magnetic flux through an arbitrary closed surface equals zero. Mathematically, in differential form: ∇ . B = 0 and in integral form: Φ_{B} = ∫B.dS = 0 (closed surface integral). This is one of the four → Maxwell's equations. This law expresses the fact that there are no free magnetic poles (→ monopoles) in nature and that all the lines of force of a magnetic field are closed curves. |
Gauss's lemma nehak-e Gauss Fr.: lemme de Gauss If a → polynomial with → integer coefficients can be → factorized into polynomials with → rational number coefficients, it can be factorized using only integers. |
Gauss's theorem farbin-e Gauss Fr.: théorème de Gauss The total normal induction over any closed surface drawn in an electric field is equal to 4π times the total charge of electricity inside the closed surface. Gauss's theorem applies also to other vector fields such as magnetic, gravitational, and fluid velocity fields. The theorem can more generally be stated as: the total flux of a vector field through a closed surface is equal to the volume → integral of the vector taken over the enclosed volume. Also known as → divergence theorem, Ostrogradsky's theorem, and Gauss-Ostrogradsky theorem. |
Gaussian Gaussi (#) Fr.: gaussien Of or relating to Carl Friedrich Gauss or his mathematical theories of magnetism, electricity, astronomy, or probability. → Gaussian distribution; → Gaussian profile. → gauss. |
<< < -ge Gal gal Gal gam gas Gau gen gen geo geo geo gia glo gol gra gra gra gra gre gri gui > >>