An Etymological Dictionary of Astronomy and Astrophysics

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory



Number of Results: 10 Search : change
adiabatic change
  دگرشد ِ بی‌دررو، دگرش ِ ~   
degaršod-e bidarrow, degareš-e ~

Fr.: changement adiabatique   

A change taking place in a system that has perfect thermal insulation, so that heat cannot enter or leave the system and energy can only be transferred by work.

adiabatic; → change.

canonical change
  دگرشد ِ هنجاروار، دگرش ِ ~   
degaršod-e hanjârvâr, degareš-e ~

Fr.: changement canonique   

A periodic change in one of the components of the orbit of a celestial object.

canonical; → change.

  ۱) گلنیدن؛ ۲) گلناندن؛ ۳) آلشیدن؛ ۴) گلن، گلنه   
1) galnidan; 2) galnândan; 3) âlešidan; 4) galn, galne

Fr.: 1, 2) changer; 3) changement   

1) (v.intr.) To undergo change.
2a) ( To → alter, modify, or make different; to make to pass from one state to another; to → exchange.
2b) To transform or convert.
3) To substitute another or others for; exchange for something else, usually of the same kind.
4) The act of changing; alteration or variation of any kind. → adiabatic change, → canonical change, → polytropic change, → secular change, → exchange.

M.E., from O.Fr. changier, from L.L. cambiare, from L. cambire "to exchange, barter," of Celtic origin, cf. Breton kamm "curved, bent;" Gk. kampe "a corner, a joint;" L. campus "a field;" Lith. kampus "corner;" PIE *kamb- "to bend, crook."

Galnidan, variant of gardidan, gaštan "to change, to turn," → Universe, cf. Awromani gelnây, geln- "to turn over" (Cheung 2007).

charge exchange
  گهولش ِ بار   
gahuleš-e bâr

Fr.: échande de charge   

A collisional process in which an → ion collides with a neutral → atom or → molecule and captures one of its electrons. One of the most important charge-exchange processes occurring in the → interstellar medium is: O+ + H → H+ + O + 0.020 eV.

charge; → exchange.

  ۱) گهولیدن؛ ۲) گهول، گهولش   
1) gahulidan (#); 2) gahul, gahuleš

Fr.: 1) échanger; 2) échange   

1) To give and receive reciprocally.
2) The act, process, or an instance of exchanging. → exchange force, → exchange particle, → Prevost's law of exchanges.

O.Fr. eschangier, from V.L. *excambiare, from L. → ex- "out" + cambire "barter."

Mod.Pers. gahulidan "to exchange," Kurd. guhartin/guhêr- "to exchange," Mid.Pers. wihir "to change," wihirišn "change," Manichean Mid.Pers. hr'g; Buddhist Mid.Pers. hlg "duty, tribute; work, effort;" Arm. loanword hark "duty, tribute;" Ar. loanword xarj "expense," xarâj "land, property tax;" Proto-Iranian *har- "to barter, trade; to pay tribute;" IE cognates: Gk. elein "to take (by force)," elor "loot, booty, catch;" Goth. saljan "to bring, to sacrifice;" O.E. sellan "to hand over, sell;" O.H.G. sala "delivery of goods."

exchange force
  نیروی ِ گهولی   
niru-ye gahuli

Fr.: force d'échange   

The force that governs the exchange of particles in the interaction between bodies. → exchange particle.

exchange, → force.

exchange particle
  ذره‌ی ِ گهولی   
zarre-ye gahuli

Fr.: particule d'échange   

In quantum field theory, a particle that transfers momentum and energy between interacting objects, and is said to mediate the interaction. All four of the fundamental forces involve the exchange of one or more particles. For example, photon is the exchange particle of the electromagnetic force.

exchange, → particle.

polytropic change
  دگرشد ِ بُلگشتی، دگرش ِ ~   
degaršod-e bolgašti, degareš-e ~

Fr.: changement polytropique   

A change in the → pressure or → volume of a → gas in a → polytropic process.

polytropic; → change.

Prevost's law of exchanges
  قانون ِ گهولش ِ په‌ره‌وُ   
qânun-e gahuleš-e Prévost

Fr.: loi des échanges de Prévost   

A statement concerned with thermodynamic heat exchange, according to which bodies in → thermal equilibrium are simultaneously absorbing and emitting radiant energy. A body radiates in the same way whether other bodies are present or not. Also called Prevost's theory of exchanges.

Named after Pierre Prévost (1751-1839), a Swiss philosopher and physicist, who, in 1791, put forward the statement; → law; → exchange.

secular change
  دگرشد ِ دیریاز، دگرش ِ ~   
degaršod-e diryâz, degareš-e ~

Fr.: changement séculaire   

A continuous, non-periodic change in one of the attributes of the states of a system. Often, a change in an orbit due to dissipation of energy. See also → canonical change.

secular; → change.