Lambda

From Wikipedia, the free encyclopedia

Look up Λ or λ 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

"Labda" redirects here. For the mythological figure, see Labda (mythology).

Lambda (uppercase Λ, lowercase λ; Greek: Λάμβδα or Λάμδα, Lamda) is the 11th letter of the Greek alphabet. In the system of Greek numerals it has a value of 30. It was derived from the Phoenician letter Lamed . Letters that arose from Lambda include the Roman L and the Cyrillic letter El (Л, л). The ancient Grammarians and dramatists attest to a pronunciation of /laːbdaː/ (λάβδα) in classical times.^[1] In Modern Greek the name of the letter, Λάμδα, is pronounced [lamða]; the letter itself is pronounced [l] as with Latin L.

In early Greek alphabets, the shape and orientation of lambda varied.^[2] Most variants consisted of two straight strokes, one longer than the other, connected at their ends. The angle might be in the upper left, lower left ("Western" alphabets), or top ("Eastern" alphabets). Other variants had a vertical line with a horizontal or sloped stroke running to the right. With the general adoption of the Ionic alphabet, Greek settled on an angle at the top; the Romans, borrowing from Western alphabets, put the angle at the lower left.

Contents 1 Symbol 1.1 Upper-case letter Λ 1.2 Lower-case letter λ 2 Lambda, the word 3 Lambda as a name 4 Half Life 5 See also 6 References

[edit] Symbol

[edit] Upper-case letter Λ

• The lambda particles in particle physics.
• The set of logical axioms in the axiomatic method of logical deduction in first-order logic.
• Used as a shield pattern by the Spartan army; it stood for Lakedaimon, the name of the region.
• The von Mangoldt function in number theory.
• In statistics, Wilks' lambda is used in multivariate analysis of variance (MANOVA) to compare group means on a combination of dependent variables.
• In spectral decomposition of matrices, a diagonal matrix of eigenvalues of the decomposed matrix.
• In computer science, the time window over which a process is observed for determining the working memory set for virtual memory management.
• In astrophysics, the likelihood that a small body will encounter a planet or dwarf planet leading to a deflection of a particular magnitude. An object with a large value is expected to have cleared its neighborhood, satisfying the current definition of a planet.
• In crystal optics, it is used to represent the period of a lattice.
• In NATO military operations, a chevron (Lambda symbol) is painted on coalition force vehicles for identification.
• In Electrochemistry, denotes the Equivalent conductance of an electrolyte.
• In cosmology, the symbol for the cosmological constant.

[edit] Lower-case letter λ

• A non-SI unit of measure of volume (symbol λ) equal to one microlitre (1 μL) or one cubic millimetre (1 mm³). This now-rare use is deprecated.
• The wavelength of a wave in physics/radio sciences
• In physics, linear charge density of a uniformly charged line(measured in C/m).
• The radioactive decay constant (Connected to half-life of a radioactive isotope in physics)
  • Copyrighted symbol of Valve Corporation, used throughout the Half-Life games.
• The lambda phage virus in biology
• In mathematical logic and computer science, used to introduce a function expression in the lambda calculus.
• In formal language theory and computer science, the empty string.
• In telecommunications, a frequency/wavelength on a WDM optical transport system
• Eigenvalues in linear algebra
• Lagrange multipliers in calculus
• Lebesgue measure in set theory
• Goodman and Kruskal's lambda is a statistic that gives the proportional reduction in error when one variable's values are used to predict the values of another variable.
• stoichiometric air to fuel ratio oxygen sensor in an internal combustion engine's exhaust gas
• A Japanese rocket type, Lambda (rocket)
• The failure rate in hours (also the reciprocal of MTBF) in reliability theory.
• In criminology, the individual offending frequency.
• In cartography and navigation, longitude.
• Christopher Langton's parameter for classification Stephen Wolfram's classes of cellular automata
• In Electrochemistry is used to denote the ionic conductance for a given ion (The ion is generally shown as a subscript to the lambda character).
• In Neurobiology is the Length constant or exponential rate of decay of potential across a membrane along a length of axon.
• In Heat Transfer, is used to denote the heat of vaporization per mole or latent heat.^[3]
• In celestial and coastal Navigation Lambda (lower case) denotes longitude as opposed to the Roman L which denotes latitude.
• Louis XIII of France used the Lambda as his personal symbol instead of a monogram.
• A symbol of the LGBT community, popular in the 1970s and 1980s.
• In naming in the United States, sometimes coupled after the letter A to idiosynchronously refer to the given name Amanda
• In Volvo cars it is used to represent engine, fuel, or ignition system fault

[edit] Lambda, the word

• In anatomy, the lambda is that point on the skull where the two parietal bones and the occipital bone come together. The configuration of the sutures resembles an upper case lambda, and the suture between each parietal bone and the occipital bone is called the lambdoid suture.
• In programming languages such as Lisp and Python, lambda is an operator used to denote anonymous functions or closures, following lambda calculus usage.
• The language Unlambda is a functional programming language based upon combinatory logic, a simplification of the lambda calculus that does not involve the lambda at all, hence the un- prefix.
• An automotive oxygen sensor is also known as an O2 sensor, lambda probe, lambda sensor and lambda sound
• Lambda is used in art and photography to refer to a digital Type C print or the equipment used to produce it.

[edit] Lambda as a name

• Lambda as a name of a small fraternity in Southern Illinois.
• The popular science fiction universe of Star Wars uses a transport vehicle known as the Lambda-class shuttle that when viewed forward has the shape of the lowercase lambda.
• Lambda is occasionally used in graphic design to represent stylized As. Examples include the Disney movie Atlantis: The Lost Empire, the logo of the band Angels & Airwaves, the logo of the band Dream Theater, and the logo of electronics company Samsung. Conversely, the name of the band Λucifer (pronounced lucifer) is sometimes spelt Aucifer.

• Stargate SG-1 uses a modified upper-case lambda, with a small circle above the apex, to indicate Earth. This symbol has since become associated with the entire franchise.
• In the Half-Life series of computer games, the 'a' in the title is replaced by the lower case lambda symbol (λ is also the Roman cursive equivalent of the letter 'a'). Also, the Lambda Complex and the protagonist Gordon Freeman's suit both feature a lower-case lambda symbol. In Half-Life 2, the 'a' in the title is also replaced by the lower case lambda symbol and the symbol is also the logo for The Resistance(Representing liberty, since it looks like an L). The robotic Dog and graffiti sprayed around City 17 also features the symbol. The main reason the lambda was used frequently throughout the series, is because in science and mathematics, the lambda symbol is the decay constant, a positive constant used to describe the rate of exponential decay in a half-life.
• In the book Otherland, Lambda is used to describe a huge Virtual Reality area of the Net known as the Lambda Mall which contains every shop on the net.
• As a bonus following the conclusion of the X-DAY manga, by Mizushiro Setona, the second book features a short tale entitled "The Last Supper." Its protagonist is a cow, genetically modified to have more human features, Lambda 26. The lambda character is tattooed on the outside of his right forearm.
• GM Lambda platform, a crossover SUV automobile platform from General Motors
• Lancia Lambda, a historic Italian automobile.
• The name of the Nerds' fraternity in Revenge of the Nerds film series was Lambda Lambda Lambda, or "the Tri-Lambs." The logo consisted of three capital Lambda letters inside a triangle.
• In the popular anime series Full Metal Panic! A select few Arm Slaves possess the device called the Lambda Driver which can manifest emotional thought patterns into raw and devastating physical power.
• /lambda/ is the name of a premium olive oil from Greece that is produced with Koroneiki olives, it is created through the process of common pressing, where carefully selected olives are hand-picked from the tree and pressed the same day.
• In the Sailor Moon manga, the character Sailor Cosmos claimed to have the ultimate "Lambda Power."
• Is the one of the main antagonists in Wild Arms: The 4th Detonator.
• In the video game Skies of Arcadia, the character Aika uses an attack known as Lambda Burst. In fact, all her attacks are based on Greek letters.
• Lambda is a name of an electrostatic headphone made by the audio company Stax Earspeakers. It is also a name of an amp made by Z-audio.
• Lambda Acid is also the name of a synthesis item in the online action RPG, Phantasy Star Universe.
• Lambda Ltd. is the name of a large technology company in the Custom Robo series of video games.
• The latest installment of the Guilty Gear series of games is called Guilty Gear XX Λ Core, commonly pronounced as "Guilty Gear Accent Core".
• Lambda Legal is a gay & lesbian legal advocacy group in the United States.
• Lambda Literary Awards is the name of a group of U.S. book awards presented annually for gay and lesbian literature.
• Lambda Particles is the name for the LGBT group at the Stanford Linear Accelerator Center.
• Lambda Rising is a gay & lesbian bookstore in the Dupont Circle neighborhood of Washington, D.C. which created the Lambda Literary Award in 1989.
• National LambdaRail is a research high-speed computer network.
• Lambda Americas is a manufacturer of power supplies that was founded in 1948.
• Hyundai Motors uses Lambda to identify their 3.8 liter V6 engine.
• Lambda is the name used by Durst for a series of digital printers using LEDs to print directly onto Silver Halide Photographic paper.
• The progressive metal band Dream Theater uses the capital Lambda (as well as capital Phi and capital Mu) in their wordmark known as the "Majesty Symbol"
• LAMBDA: Least-squares AMBiguity Decorrelation Adjustment^[4]
• A witch in the visual novel Umineko no Naku Koro ni has the name Lambda combined with Delta.

[edit] Half Life

The Half Life series by Valve use the Lambda symbol as their logo. They also sometimes replace the 'A' in Half to a lower case Lambda. There are many different theories of why the lambda sign is used in Half Life:

1. It's used in science equations when figuring out the half life of an element which made it the right symbol for Half Life

2. It's the symbol for the radioactive decay constant in the equation for half-life.

3. It means "G" which is the first letter of Gordon Freeman's name.

4. It means "G" which is the first letter of the G-Man's name.

[edit] See also

• Greek letters used in mathematics, science, and engineering
• Л, л - El (Cyrillic)
• Half Life (series)

[edit] References

1. ^ Herbert Weir Smyth. A Greek Grammar for Colleges. I.1.c
2. ^ Poinikastas: Epigraphic Sources for Early Greek Writing
3. ^ Wankat Separation Process Engineering 2nd ed, Prentice Hall
4. ^ resolution of GPS ambiguities.[1]