1) senn (#); 2) asr (#)
1) The length of time that a celestial body or an evolutionary
stage of it has existed, i.e. the age of a
massive star, the age of a galaxy, a stellar cluster, and so on.
From O.Fr. aage, from Vulgar L. *ætaticum, from L. ætatem "period of life," from ævum "lifetime, eternity, age;" cf. Mid.Pers. awâm, âwâm "time, season," Av. âyav- "duration, period, time of life," Skt. âyuh- "life, health". All from PIE *aiw-, *ayu- "vital force, life, long life, eternity."
Senn from Ar. senn "age, lifetime". Asr from Ar.
age of the Moon
1) kohan-ruzi-ye mâh; 2) senn-e mâh
Fr.: âge de la lune
Same as → Moon's age.
→ Moon's age.
age of the Universe
Fr.: âge de l'Univers
The time elapsed since the → Big Bang.
Agena (β Centauri)
Alternative name for the star Hadar, the second brightest star in Centaurus and the tenth brightest star in the sky. → Hadar.
The etymology of Agena is not clear. Some sources have suggested L. a genu "by the knee," but it seems dubious.
1) Something such as a chemical substance, organism, or natural force that causes an effect.
From L. agentem (nominative agens, genitive agentis), pr.p. of agere "to set in motion, drive, lead, conduct," → act.
Konešgar, from koneš verbal noun of kardan "to do, to make" (Mid.Pers. kardan, O.Pers./Av. kar- "to do, make, build," Av. kərənaoiti "makes," cf. Skt. kr- "to do, to make," krnoti "makes," karma "act, deed;" PIE base kwer- "to do, to make") + -gar, → -or.
Fr.: vent agéostrophique
Meteo.: The wind component deviating from the → geostrophic wind in the absence of the → geostrophic balance. In other words, ageostrophic wind is the difference between the true wind and the geostrophic wind.
A comprehensive treatise, compiled by Claudius Ptolemy of Alexandria, around A.D. 140, that summarized the astronomy, geography, and mathematics of antiquity, and included a star catalogue with data for 1,022 stars.
Almagest, from Ar. Al-majisti, from al "the" + Gk. megiste (suntaxis) "the greatest (composition)," from femenine of megistos, superlative of megas "great."
Fr.: langue analytique
A language that is characterized largely by the fact that it depends on word order, rather than on inflections (grammatical endings), to convey sentence meanings. In an analytic language relations between nouns and adjectives are expressed using prepositions. English and (to a lesser extent) French, and Persian are considered analytic languages, while German and Russian are → synthetic languages.
Fr.: langue artificielle
An artificially created language system for international communication or for a specific intellectual or scientific purpose. Examples include Esperanto, computer programing languages, → symbolic logic, and → tensor analysis.
A number representing a group of quantities, obtained by adding each quantity of the group and dividing the total by the number of quantities. Same as → arithmetic mean.
From O.Fr. avarie "damage to ship," from It. avaria or maybe avere, O.Fr. aveir "property, goods," from L. habere "to have." Meaning shifted to "equal sharing of such loss by the interested parties."
Miyângin "the middle; middle-sized; the middle pearl in a string," from miyân, → middle, + -gin a suffix forming adjectives of possession.
Fr.: accélération moyenne
Of a body traveling from A to B, the change of → velocity divided by the time interval: ā = (v2 - v1) / (t2 - t1).
Fr.: vitesse moyenne
The ratio of the displacement (Δx) of a particle, as it moves from point A to point B, to the corresponding time interval: v = Δx/Δt.
Fr.: voltage de biais
A voltage applied or developed between two electrodes as a bias.
tasvir-e târ, ~ nâtig
Fr.: image estompée, ~ floue
asr-e boronz (#)
Fr.: âge du fer
A period of time between the → Stone Age and the → Iron Age when bronze was used widely to make tools, weapons, and other implements. The Bronze Age starts at different areas of the world at different times. The earliest use of bronze for making farm tools and weapons are found in Near and Middle East and date back to about 3700 BC. The Bronze Age starts about 2300 BC in Europe.
M.E. from O.Fr. cage, from L. cavea "hollow place, enclosure for animals," cognate with Pers. kâv "hollow," → concave.
Qafas "cage," of unknown origin.
Fr.: âge caractéristique
Of a pulsar, a normalized period of rotation assumed to be a good approximation to pulsar's true age.
Fr.: image intégrée
An image made up of several individual images of relatively short exposure times which are added together in order to produce a final image of higher quality.
Fr.: interprétation de Copenhague
A general heading which covers a wide variety of complex views on → quantum theory. As the first and the founding interpretation of the → quantum mechanics, it was developed in the late 1920's mainly by the Danish physicist Niels Bohr, but also Werner Heisenberg, Max Born and other physicists who made important contributions to the overall understanding of this field. Bohr expressed himself on the subject at various meetings and later published several articles and comments, but he never wrote a systematic and complete version of his views. There is not a unique Copenhagen Interpretation but various more or less complete versions, the common denominator of which is mainly the work of Bohr. Among those opposed to the Copenhagen Interpretation have been Albert Einstein, Erwin Schrödinger, Louis de Broglie, Max Planck, David Bohm, Alfred Landé, Karl Popper, and Bertrand Russell. The Copenhagen Interpretation recognizes that the deterministic picture of the universe that works so well at the macroscopic level does not work for the world at the quantum level. The universe at the quantum level is predictable only in a statistical sense. This implies that we can never really know the nature of quantum phenomena. The four cornerstones of the Copenhagen Interpretation are: → wave-particle duality, the probability → wave function, the → uncertainty principle, and the significance of the → observer. The observer is of the utmost importance because he causes the reality to unfold in the way it does. The key feature of the Copenhagen Interpretation is a concept known as the → collapse of the wave function, for which there is no known physical explanation; see also → Schrodinger's cat.
Copenhagen, from Dan. København "merchant's port," from køber "merchant" ("buyer") + havn "port," from the fact that the originator and chief interpreter of this school was Niels Bohr whose headquarters was in Copenhagen; → interpretation.
Cosmic Dark Age
asr-e târik-e keyhâni
Fr.: âge sombre cosmique