Gamma

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Look up Γ or γ in Wiktionary, the free dictionary.

Greek alphabet
Αα	Alpha	Νν	Nu
Ββ	Beta	Ξξ	Xi
Γγ	Gamma	Οο	Omicron
Δδ	Delta	Ππ	Pi
Εε	Epsilon	Ρρ	Rho
Ζζ	Zeta	Σσς	Sigma
Ηη	Eta	Ττ	Tau
Θθ	Theta	Υυ	Upsilon
Ιι	Iota	Φφ	Phi
Κκ	Kappa	Χχ	Chi
Λλ	Lambda	Ψψ	Psi
Μμ	Mu	Ωω	Omega
Obsolete letters
	Digamma		Qoppa
	San		Sampi
Other characters
	Stigma		Sho
	Heta
Greek diacritics

Gamma uppercase Γ, lowercase γ; Greek: Γάμμα) is the third letter of the Greek alphabet. In the system of Greek numerals it has a value of 3. It was derived from the Phoenician letter Gimel . Letters that arose from Gamma include the Roman C and G and the Cyrillic letters Ge Г and Ghe Ґ.

In Modern Greek, it represents either a voiced velar fricative /ɣ/ or a voiced palatal fricative /ʝ/. In Ancient Greek, it represented a voiced velar stop /ɡ/. Before velars, it represents a velar nasal /ŋ/ in Modern as well as Ancient Greek, and a double gamma represents the sequence /ŋɡ/ (phonetically varying [ŋɡ~ɡ]) or /ŋɣ/.

[edit] Gamma combinations

The gamma can be combined with other letters or itself.

• A double gamma (γγ) is pronounced like the ng in "finger"
• A gamma with xi (γξ) is pronounced roughly like the nx in "sphinx"
• (γχ) is pronounced like the nkh in "ankh"
• A gamma combined with kappa (γκ) is pronounced like the nk in "banker"

[edit] Use as a symbol or a term

The lower-case letter γ is used as a symbol for:

• gamma radiation in nuclear physics
• surface energy in materials science
• the Lorentz factor in theory of relativity
• The heat capacity ratio Cp/Cv in thermodynamics
• gamma oscillation in neuroscience
• the power by which the luminance of an image is increased in gamma correction
• The Euler–Mascheroni constant
• Phonetics uses gamma as the symbol for the voiced velar fricative
• In mechanical engineering,
  • specific weight
  • The shear rate of a fluid is represented by a lower case gamma with a dot above it:

The upper-case letter Γ is used as a symbol for:

• In mathematics, the gamma function (usually written as Γ-function) is an extension of the factorial to complex numbers
• circulation in fluid mechanics
• As reflection coefficient in physics and electrical engineering

[edit] See also

• Г, г - Ge (Cyrillic)
• G, g - Latin
• photon