This article is about the letter. For other uses, see Gamma (disambiguation).

In Modern Greek, it is pronounced or . In Ancient Greek, it was pronounced . Before velars, it represents a in Modern as well as Ancient Greek, and a double gamma is pronounced ).

Use in science

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Gamma is often used to denote a variable in mathematics and physics. In certain areas it has specific meaning.

• Gamma correction in photography, television and computer display systems. Gamma is the exponent in a power-law relationship between video or pixel values and the displayed brightness. In photography it is the slope of the curve of (density or log(opacity)) of the film image versus log(exposure) (the Hurter-Driffield curve), in the straight line region.
• 1 gamma is a unit of magnetic flux density, 1 gamma = 10⁻⁹ tesla or 1 nanotesla.
• Gamma waves are a type of brain waves around 40 hertz.
• Gamma rays are the highest point on the electromagnetic spectrum.

Upper-case

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

• The gamma function (related to factorials) in mathematics.
• The Gamma distribution in probability theory and statistics.
• The Christoffel symbol in General Relativity.
• The reflection coefficient in electrical engineering.
• The linewidth relating to uncertainty of mass energy in short-lived particles.

Lower-case

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

• The Euler-Mascheroni constant in mathematics.
• A risk management measure in mathematical finance.
• The photon, seen as an elementary particle in physics.
• Gamma rays in physics and astronomy.
• The Lorentz factor in relativity theory and astronomy.
• The adiabatic index of a gas in physics. Often the letter kappa κ is used.
• The propagation constant of an electromagnetic wave (in electrical engineering and electromagnetic theory).
• The third brightest (usually) star in a constellation. See Bayer designation.
• A microgram. This use is deprecated by the SI.

Fictional names

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• MA-124 Gamma Hunters, mutant frog monsters from the Resident Evil series.
• In the game of Tetris, gamma is another name for the J tetromino.
• E-102 Gamma is a fictional robotic character in the Sonic the Hedgehog universe.
• Gamma is a giant peace-keeping robot stolen by Dr. Wily which is the final boss of Capcom's Nintendo game Mega Man 3.
• Gamma is the third caste in Aldous Huxley's dystopic satire Brave New World.
• The Nintendo character Waluigi has an upside-down "L" on his hat the looks like "Γ" to some people, keeping in theme with Wario's upside-down "M".
• Gamma is a term coined by Neuros Technology to describe a product stage that is pre-production but "post beta"

Trivia

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• Tropical Storm Gamma is the third Atlantic tropical storm to be named using the Greek alphabet.

Greek letters

Γ | Gamma (lizherenn) | Гама (буква) | Gamma | Gamma (bogstav) | Gamma | Γάμμα | Γ | Gamma (greko) | Gamma | Gáma | Gamma | Γ | Gamma (lettera) | גמא (אות) | Gamma | Gamma (letter) | Γ | Gamma | Gamma | Gamma | Gamma | Γ | Гамма (буква) | Gama | Гама | Gamma | Gamma