Gamma

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
Other characters
	Digamma		Stigma
	Heta		San
	Qoppa		Sampi
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/.

Use as a symbol or a term

The lower-case letter $\gamma$ 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
The activity coefficient in thermodynamics
The gyromagnetic ratio in electromagnetism
gamma oscillation in neuroscience
Gamma Motor Neurons in neuroscience
antibiotic concentration (1 $\gamma$ = 1 µg/ml) in microbiology
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: $\dot \gamma$
- Austenite (also known as γ-iron), a metallic non-magnetic allotrope or solid solution of iron.

The upper-case letter $\Gamma$ is used as a symbol for:

In mathematics, the gamma function (usually written as $\Gamma$ -function) is an extension of the factorial to complex numbers
In probability theory and statistics, the gamma distribution is a two-parameter family of continuous probability distributions.
circulation in fluid mechanics
As reflection coefficient in physics and electrical engineering
The tape alphabet of a Turing machine

Gamma

Use as a symbol or a term

See also