Same as → gegenschein.
Fr.: énergie noire
A hypothetical form of energy that fills all the space and tends to increase the rate of expansion of the Universe. Assuming the existence of dark energy is a way to explain recent observations that the Universe appears to be expanding at an increasing rate (→ accelerating Universe). Dark energy seems to be a kind of anti-gravity force and is supposed to be related to → vacuum energy. Where gravity pulls things together at the more local level, dark energy tears them apart on the grander scale. The acceleration equation, one of Einstein's equations for the homogeneous Universe, indicates that if the Universe is accelerating, the pressure of the driving component should be strongly negative. The dark energy density relates to the → cosmological constant via: ρ&Lambda = Λc2/(8πG), where G is the → gravitational constant and c the → speed of light. The first indication of dark energy was provided by the observation of → Type Ia supernovae. Other probes of dark energy are: → baryon acoustic oscillations, → weak gravitational lensing, and clusters of galaxies. In the standard model of cosmology, dark energy currently accounts for almost 74% of the total mass-energy of the Universe. Two proposed forms for dark energy are the cosmological constant and exotic component such as → quintessence.
Fr.: énergie de dissociation
Energy required to dissociate a molecule. → dissociate.
(v.intr.) To move, or extend in different directions from a common point.
M.L. divergere, from → di- "apart," variant of → dis- + vergere "to bend, turn, incline," from PIE *werg- "to turn," from base *wer- "to turn, bend" (cf. L. vertere "to turn," Av. varət- "to turn," Mod.Pers. gard, gardidan "to turn," Skt. vartate "turns round, rolls," Gk. rhatane "stirrer, ladle," Ger. werden, O.E. weorðan "to become."
Verâyidan, from vâ- "apart," → de-, + gerâyidan "to incline toward; to intend; to make for," infinitive of gerâ, the etymology of which is not clear. Gerâ may be a variant of Mod.Pers. kil "bent, inclined" (k/g and l/r interchanges), from PIE base *klei- "to lean, incline," cognate with L. clinare "to bend" (E. declination, inclination, etc.), Gk. klinein "to cause to slope, slant, incline," Skt. sri- "to lean," O.Pers. θray-, Av. sray- "to lean," P.Gmc. *khlinen (Ger. lehnen, E. lean).
1) The act, fact, or amount of diverging.
From diverge, → diverge, + -ence a noun suffix.
Vâgerâyi, from vâgerâ stem of vâgerâyidan, → diverge, + noun suffix -i.
Fr.: théorème de flux-divergence
Same as → Gauss's theorem.
Relating to or causing divergence. Gowing away in different directions from a common
point or path.
M.L. divergent-, stem of divergens pr.p. of divergere, from → di- "apart," variant of → dis- + vergere "to bend, turn, incline," from PIE *werg- "to turn," from base *wer- "to turn, bend" (cf. L. vertere "to turn," Av. var ət- "to turn," Mod.Pers. gard, gardidan "to turn," Skt. vartate "turns round, rolls," Gk. rhatane "stirrer, ladle," Ger. werden, O.E. weorðan "to become."
Vâgerâ, agent noun from vâgerâyidan, → diverge + noun suffix -i.
adasi-ye vâgerâ (#)
Fr.: lentille divergente
A lens which causes a parallel beam of light passing through it to diverge or spread out; concave lens. Same as diverging lens and → negative lens.
Fr.: fusion sans gaz
1) Move out of or away from something and become visible.
1) The process of becoming visible after being concealed.
1) Coming into being or notice.
Fr.: rayon émergent
Fr.: processus endoénergétique
A nuclear or molecular process in which some of the energy of the incoming particle is absorbed by, or transferred to, the other particle.
→ endo- + -ergic, a combining form with the meanings "activated by, sensitive to, releasing, resembling the effect produced by the substance or phenomenon specified by the initial element," from → erg, → energy + → -ic; → process.
Farâravand, → process; kâružgir, from kâruž, → energy, + gir present stem of gereftan "to take, seize, catch" (Mid.Pers. griftan, Av./O.Pers. grab- "to take, seize," cf. Skt. grah-, grabh- "to seize, take," graha "seizing, holding, perceiving," M.L.G. grabben "to grab," from P.Gmc. *grab, E. grab "to take or grasp suddenly;" PIE base *ghrebh- "to seize").
1) kâružmand; 2) kâruži
Fr.: 1) de grande énergie, énergique; 2) énergétique
1) Having a relatively high amount of energy.
energetic solar particles
zarrehâ-ye xoršidi-ye kâružmand
Fr.: particules solaires énergétiques
Electrons and atomic nuclei ejected by solar flares, travelling with velocities amounting to a fraction of the velocity of light, and energies mostly in the range 1-100 million → electronvolts (eV), but occasionally as high as 15 billion eVs. Also known as solar → cosmic rays.
The total energy relations and transformations of energy within a particular physical, chemical, or biological system.
In physics, capacity for doing work.
From M.Fr. energie, from L.L. energia, from Gk. energeia "force in action, activity, operation," from energos "active, working," from en- "in, at" + ergon "work," from PIE base *werg- "to work" (cf. Av. varəz- "to work, do, perform, exercise;" Mod.Pers. varz-, varzidan "to labor, exercise, practise;" Arm. gorc "work;" Lith. verziu "tie, fasten, squeeze," vargas "need, distress;" Goth. waurkjan; O.E. wyrcan "work," wrecan "to drive, hunt, pursue").
Kâruž, literally "work strength," from kâr + už. The first component kâr "work," Mid.Pers kâr, Mod./Mid.Pers. kardan "to do, to work," 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 kwer- "to do, to make." The second component, už, from Mid.Pers. ôž "strength" (ôžômand "strong"), Av. aogah-, aojah- "strength" (aojahvant- "strong") Skt. ojas- "strength" (ojasvant- "strong"); L. augustus "venerable," L.L. augmentare "to increase," from augere "to increase, enlarge, enrich;" Lith. augu "to grow;" Gk. auxo "increase;" Goth. aukan "to grow, increase;" O.E. eacien "to increase"); PIE *augos- "force," *aug- "to increase."
Fr.: cascade d'énergie
The → turbulent process whereby → kinetic energy is transformed into heat by the action of nonlinear coupling which transfers the energy from large eddies (→ eddy) to smaller and smaller eddies, finally arriving at → dissipative scales dominated by → viscosity (direct cascade). In the simplest case (3D homogeneous hydrodynamic turbulence), the resulting energy distribution is the → Kolmogorov spectrum. The reverse process also exists (inverse cascade) whereby energy is transferred to larger and larger eddies.
Fr.: densité d'énergie
The amount of energy in the form of radiation per unit volume, expressed in ergs cm-3. In particular, the energy density of blackbody radiation at temperature T is aT4, where the radiation constant a = 7.56 × 10-15 erg cm-3 (K)-4.