Big Bang theory
negare-ye Meh Bâng, ~ Big Bang
Fr.: théorie du big bang
big blue bump
quz-e âbi-ye bozorg
Fr.: grande bosse bleue
The broad continuum feature dominating the optical-ultraviolet spectra of AGNs. Most current models attribute the big blue bump to thermal emission from an optically thick accretion disk.
Meh Romb, rombeš-e farjâmin
Fr.: big crunch
The state of extremely high density and temperature into which a closed → Universe would → collapse in the distant future. If the Universe has a mass density exceeding the critical threshold, then gravity will eventually halt the expansion and cause the Big Crunch.
→ big; crunch "to crush, grind, or tread noisily; the act or sound of crunching," alteration of craunch, possibly of imitative origin.
haft barâdarân (#), haftowrang (#), camce-ye bozorg (#)
Fr.: Grand Chariot
A group of seven stars, an → asterism, lying inside the Northern constellation → Ursa Major. They are: → Dubhe, → Merak, → Phad, → Megrez, → Alioth, → Mizar, and → Alkaid. The group is also known as the Plough in Great Britain.
→ big; dipper a popular U.S. name for the asterism known in Britain as The Plough or Charles' Wain, from dip O.E. dyppan "immerse," from P.Gmc. *dupjanan.
Haft barâdarân "the seven brothers," from haft "seven"
(Mid.Pers. haft, Av. hapta, cf. Skt. sapta, Gk. hepta,
L. septem, P.Gmc. *sebun, Du. zeven, O.H.G. sibun,
Ger. sieben, E. seven; PIE *septm)
+ barâdarân, plural of barâdar "brother"
(Mid.Pers. brad, bardar, O.Pers./Av. brātar-, cf. Skt. bhrátar-,
Gk. phrater, L. frater, P.Gmc. *brothar;
PIE base *bhrater- "brother").
Fr.: gros grain
A type of → interstellar dust grains with a size ranging from 150 to 1000 Å. Big grains consist of graphite and silicates. They are in → thermal equilibrium with the radiation field and their emission can be described by a modified → blackbody radiation following from → Kirchhoff's law.
Fr.: big rip
A cosmological hypothesis regarding the ultimate fate of the → Universe whereby in a far future galaxies and stellar systems would be torn apart due to the → accelerating expansion of the Universe depending on the kind of the → dark energy content of the Universe. According to this hypothesis, after the disruption of galaxies, stars, and planets even atoms might not be able to withstand the internal force of the expansion imposed by the dark energy.
→ big; M.E. rippen, origin obscure, cf. Frisian rippe "to tear, rip," M.Du. reppen, rippen "to pull, jerk," Swed. reppa, Dan. rippe "to tear, rip."
Meh "large, big," see under → big; gosast stem of gosastan "to tear, cut, break," from Mid.Pers. wisistan "to break, split," Av. saed-, sid- "to split, break," asista- "unsplit, unharmed," Skt. chid- "to split, break, cut off," PIE base *skei- "to cut, split," cf. Gk. skhizein "to split," L. scindere "to split," Goth. skaidan, O.E. sceadan "to divide, separate."
A → mapping f from a → set A onto a set B which is both an → injection and a → surjection. More explicitly, for every element b of B there is a unique element a of A for which f(a) = b. Also known as → bijective mapping.
From bi- + → injection.
Of or pertaining to a → bijection.
Fr.: application bijective
Same as → bijection.
Fr.: morphisme bijectif
Same as → isomorphism.
bimodal star formation
diseš-e domodi-ye setâregân
Fr.: formation bimodale d'étoile
A concept of star formation in which high and low mass stars form at different interstellar locations.
1) bâvin; 2) bâvinidan
Fr.: 1) bin; 2) binner
1a) General:A box or enclosed space for storing grain, coal, or
M.E. binne, O.E. binn(e) "manger, crib," perhaps from O.Celt. *benna, akin to Welsh benn "a cart, especially one with a woven wicker body." The same Celtic word seems to be preserved in It. benna "dung cart," Fr. benne "a sort of box for transporting materials, especially in mines," Du. benne "large basket," from L.L. benna.
Bâvin "a basket, more precisely a small basket which contains the cotton to be spun;" bâvinidan infinitive from bâvin.
The quality or condition of being binary.
dorin, dodoyi (#)
General: Characterized by or consisting of two parts or
Binary, from L.L. binarius, from bini "two-by-two," from bis "twice, two times;" cf. Av. biš- "twice," bi- "two," Mod.Pers. do "two," PIE *dwo- "two."
Dorin, from Mid.Pers. dorin "double, pair,"
from do (Av. dva-, Skt. dvi-, Gk. duo,
L. duo, E. two, Der. zwei, Fr. deux)
"two" + rin "time, turn."
hesâb-e dorin, ~ dodoi (#)
Fr.: arithmétique binaire
A system of calculation in which the only numerals used are 0 and 1. All the real numbers are represented in terms of powers of 2.
Fr.: astéroïde binaire
A member of a population of double objects in the main → Asteroid Belt or the → Kuiper Belt which are gravitationally bound together. So far about 200 such binary systems have been identified, while their number is increasing. 243 Ida was the first binary asteroid to be discovered during the Galileo spacecraft flyby in 1993. Other examples are → Antiope and Kalliope in the main belt and QG298 in the Kuiper Belt. The importance of these objects resides in the fact that systems with well measured orbital parameters allow the total mass to be estimated. If the sizes of the components are known then their densities can be accurately calculated. Density is an important parameter since it yields information about composition and internal structure.
binary black hole
siyah câl-e dorin
Fr.: trou noir binaire
binary digit (bit)
raqam-e dorin, ~ dodoi, bit
Fr.: chiffre binaire
Either of the digits 0 or 1, used in the → binary number system.
Fr.: galaxie binaire
A pair of galaxies in orbit around each other.
→ binary; → galaxy.
binary number system
râžmân-e adadhâ-ye dirini
Fr.: système des nombres binaires
A → numeral system that has 2 as its base and uses only two digits, 0 and 1. The positional value of each digit in a binary number is twice the place value of the digit of its right side. Each binary digit is known as a bit. The decimal numbers from 0 to 10 are thus in binary 0, 1, 10, 11, 100, 101, 110, 111, 1000, 1001, and 1010. And, for example, the binary number 111012 represents the decimal number (1 × 24) + (1 × 23) + (1 × 22) + (0 × 21) + (1 × 20), or 29. In electronics, binary numbers are the flow of information in the form of zeros and ones used by computers. Computers use it to manipulate and store all of their data including numbers, words, videos, graphics, and music.