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Martin van Creveld

Martin Levi van Creveld (מרטין לוי ון קרפלד, ; born 5 March 1946) is an Israeli military historian and theorist.

Life and career
Van Creveld was born in the Netherlands in the city of Rotterdam to a Jewish family. His parents, Leon and Margaret, were staunch Zionists who had managed to evade the gestapo during World War II.

In 1950, his family immigrated to Israel, and Creveld grew up in Ramat Gan. From 1964 to 1969, he studied history at the Hebrew University of Jerusalem and earned an M.A. From 1969 to 1971, he studied history at the London School of Economics and received a PhD. His thesis was titled Greece and Yugoslavia in Hitler's strategy, 1940–1941.

Van Creveld's doctoral dissertation on Hitler's strategy in the Balkans during the early years of World War II was published as a book in 1973: "Hitler's Strategy, 1940–41. The Balkan Clue." After completing his PhD in 1971, van Creveld returned to Israel and began teaching at the Hebrew University of Jerusalem. He became a professor in 1988. In 2007, he retired from teaching at Hebrew University, and began teaching at Tel Aviv University's Security Studies Program.

Van Creveld has been married twice and has three children. He lives in Mevaseret Zion.

Books
Van Creveld is the author of thirty-three books on military history, strategy, and other topics, of which Command in War (1985), Supplying War: Logistics from Wallenstein to Patton (1977, 2nd edition 2004), The Transformation of War (1991), The Sword and the Olive (1998) and The Rise and Decline of the State (1999) are among the best known. Van Creveld has lectured or taught at numerous civilian and military institutes of higher learning all over the world.

The Transformation of War
Of particular significance is his 1991 book The Transformation of War (UK: On Future War), which was translated into French, German (New German edition in 2004), Russian, and Spanish. In this treatise of military theory, van Creveld develops what he calls the non-trinitarian theory of warfare, which he juxtaposes to the famous work by Clausewitz, On War.

Clausewitz's trinitarian model of war (a term of van Creveld's) distinguishes between the affairs of the population, the army, and the government. Van Creveld criticizes this philosophy as too narrow and state-focused, thus inapplicable to the study of those conflicts involving one or more non-state actors. Instead, he proposes five key issues of war:
 * 1) By whom war is fought – whether by states or by non-state actors
 * 2) What is war all about – the relationships between the actors, and between them and the non-combatants
 * 3) How war is fought – issues of strategy and tactics
 * 4) What war is fought for – whether to enhance national power or as an end to itself
 * 5) Why war is fought – the motivations of the individual soldier

Van Creveld notes that many of the wars fought after 1945 were low-intensity conflicts (LICs) which powerful states ended up losing. The book argues that we are seeing a decline of the nation-state, without a comparable decline in organized violence. Moreover, in his view, armies consistently train and equip to fight a conventional war, rather than the LICs they are likely to face. Consequently, it is imperative that nation-states change the training of their armed forces and rethink their weapon procurement programs.

The book's significance is attested to by the fact that until the middle of 2008, it was included on the list of required reading for United States Army officers, and (with Sun Tzu and Clausewitz) the third non-American entry on the list. Van Creveld's Supplying War: Logistics from Wallenstein to Patton is now included on the list as well.

In a commander's quest for certainty in battlefield information, Van Creveld popularized "directed telescope" as a term to describe the use of specially selected and trusted officers as special agents or observers for the commander".

The Privileged Sex
In addition to his books on military history, van Creveld has written several books on other issues. The most prominent of these is perhaps his anti-feminist polemic The Privileged Sex (2013). In the book, van Creveld argues that the systematical oppression of women (as claimed by feminists) is a myth unsupported by any serious data and that women tend to enjoy more social protections and privileges than do men.

Views on current affairs
In addition to writing on military history, van Creveld also comments, often pointedly, on contemporary societies and politics.

In a TV interview in 2002, he expressed doubts as to the ability of the Israeli army to defeat the Palestinians:

"They [Israeli soldiers] are very brave people... they are idealists... they want to serve their country and they want to prove themselves. The problem is that you cannot prove yourself against someone who is much weaker than yourself. They are in a lose-lose situation. If you are strong and fighting the weak, then if you kill your opponent then you are a scoundrel... if you let him kill you, then you are an idiot. So here is a dilemma which others have suffered before us, and for which as far as I can see there is simply no escape. Now the Israeli army has not by any means been the worst of the lot. It has not done what for instance the Americans did in Vietnam... it did not use napalm, it did not kill millions of people. So everything is relative, but by definition, to return to what I said earlier if you are strong and you are fighting the weak, then anything you do is criminal."

In a September 2003 interview in Elsevier, a Dutch weekly, on Israel and the dangers it faces from Iran, the Palestinians and world opinion van Creveld stated, referring to the Samson Option:

"We possess several hundred atomic warheads and rockets and can launch them at targets in all directions, perhaps even at Rome. Most European capitals are targets for our air force…. We have the capability to take the world down with us. And I can assure you that that will happen before Israel goes under."

On 21 August 2004 edition of the International Herald Tribune van Creveld wrote, "Had the Iranians not tried to build nuclear weapons, they would be crazy."

In 2005, van Creveld made headlines when he said in an interview that the 2003 invasion of Iraq was "the most foolish war since Emperor Augustus in 9 BC [sic] sent his legions into Germany and lost them", a reference to the Battle of the Teutoburg Forest. His analysis included harsh criticism of the Bush administration, comparing the war to the Vietnam war. Moreover, he said that "Bush deserves to be impeached and, once he has been removed from office, put on trial."

In 2007, van Creveld commented that

"Iran is the real victor in Iraq, and the world must now learn to live with a nuclear Iran the way we learned to live with the nuclear Soviet Union and a nuclear China.... We Israelis have what it takes to deter an Iranian attack. We are in no danger at all of having an Iranian nuclear weapon dropped on us.... thanks to the Iranian threat, we are getting weapons from the U.S. and Germany."

Van Creveld viewed the Second Lebanon War as a strategic success for Israel and a Hezbollah defeat. He was also highly critical of the Winograd Commission's report for its failure to note the many successes brought about by Israel's military campaign. He noted that Hezbollah "had the fight knocked out of it," lost hundreds of its members and that the organization was "thrown out of South Lebanon," replaced by "a fairly robust United Nations peacekeeping force." He also noted that as a result of the war, Israel is experiencing a level of calm on its Lebanon border not seen since the mid-1960s. More recently, in an article published in Infinity Journal in June 2011, titled "The Second Lebanon War: A Reassessment", Martin van Creveld argued that contrary to the common view, and despite "clumsy, heavy-handed, and slow" ground operations, the Second Lebanon War was a great victory for Israel. He states that as a result of the war, "since the middle of August 2006, all over southern Lebanon hardly a shot has been fired."

In an opinion piece published in The Jewish Daily Forward in 2010, van Creveld argued that the West Bank, far from being vital to Israel's security, is a territory "that Israel can easily afford to give up." Van Creveld contended that the West Bank offers no defense against ballistic missiles from Israel's two chief enemies, Iran and Syria. Furthermore, provided that it would be demilitarized in any future peace settlement with the Palestinians, the West Bank would act as a natural barrier impeding the advance of any army endeavoring to invade Israel by land from the east. Lastly, Israel could defend itself against terrorism from the West Bank by means of a wall coupled with offensive campaigns the likes of Operation Cast Lead and the Second Lebanon War, which successfully restored Israel's deterrence factor when the level of terrorism exceeded what Israel was willing to tolerate.

In an article co-authored with a Cambridge researcher of Middle Eastern history, Jason Pack, addressing the 2011 Libyan civil war, van Creveld challenged the media's tendency to portray the circumstances in Libya as being largely equivalent to those that formed the backdrop to the overthrow of ben-Ali in Tunisia and Mubarak in Egypt earlier in the year. "The remarkable spread of the 2011 Arab revolts across the face of North Africa causes many journalists to portray the current Libyan uprising as fueled by similar factors to those at play in neighboring Tunisia and Egypt. There are more differences than similarities." Van Creveld noted that Tunisia and Egypt "have been coherent nation-states for well over a century," while Libyan society is still pervasively tribalist. He also observed that whereas the armies of Tunisia and Egypt could mediate the transitions between the old regimes and the new, "Libya lacks a professional, non-tribal army" that could function in such a role. Van Creveld blamed Gaddafi's son Saif al-Islam Gaddafi for squandering a crucial opportunity to restore order to the country and confidence – both domestic and international – in the Gaddafi regime.

Van Creveld has stated that the Israeli government has "vastly exaggerated the threat that a nuclear Iran poses to its security, as well as Israel's capacity to halt it."

Syria and terrorism
In 2016, in a commentary for the German magazine Focus, Creveld advocated an alliance with the Assad regime. "If the West wants to win the war against the caliphate of terror, they cannot be picky about their allies". The regional conflict was not about a despot, but about a novel form of terrorism aiming at the dissolution of all state order and territorial boundaries in the whole region. Only the Alawite soldiers of the Assad regime were willing to die fighting the terrorists, whereas the European and American attempts to avoid bloodshed concentrating on airstrikes, were useless against Guerrilla troops as history had shown. Losing the war against IS and Al Nusra would have incalculable consequences for the Middle East and for Europe. In comparison, Assad would appear as the "lesser devil".

As early as 2013, again in the magazine Focus, he regarded support for Assad as important to avoid the destabilization of the Middle East as a whole. Assad would continue the war only to prevent a still larger carnage, the annihilation of the 1.2 million Alawites. "Instead of complaining about humanitarian concerns and arguing about arms deliveries to the rebels, the West should join Russia and press for a negotiation solution. If necessary, the West should help the rebels and allow Assad to stay on his post: he is the only person who can hold the country together." Van Creveld quoted Bismarck: "Politics is the choice between the bad and the worse." In a lecture at the Konrad-Adenauer-Stiftung in Brandenburg he pleaded to follow a "pragmatic path" in Syria.

In 2011, looking back at Bashar's father, he analyzed the strategy of Hafez Al-Assad against the town of Hama in 1982, then the center of the Muslim Brothers. Without this action, seen as extremely brutal and as a war crime by Creveld, Assad's regime would probably have been overthrown. Assad himself and many members of the Alawite community would have been killed. After Assad's removal, perhaps a stable regime would have been established by non-Alawite Muslims, or – the more likely variant in Martin van Creveld's view – there would have been no stable government at all. In this case, there would have been a war of everyone against everyone. "Judging from the experience in neighboring Beirut, such a civil war could have cost hundreds of thousands of people. And, according to what happened in Lebanon and Afghanistan, Syria could have developed into a place teeming with international terrorists of every direction."

Published works
Books

 * Hitler's Strategy 1940–1941: the Balkan Clue, Cambridge University Press, 1973, ISBN 0-521-20143-8
 * Military Lessons of the Yom Kippur War: Historical Perspectives, Beverly Hills : Sage Publications, 1975, ISBN 0-8039-0562-9
 * Supplying War: Logistics from Wallenstein to Patton, Cambridge University Press, 1977, ISBN 0-521-21730-X (2nd ed, 2004, ISBN 0-521-54657-5)
 * Fighting Power: German and US Army performance, 1939–1945, Westport, Conn. : Greenwood Press, 1982, ISBN 0-313-23333-0
 * Command in War, Cambridge, Mass. : Harvard University Press, 1985, ISBN 0-674-14440-6
 * Technology and War: From 2000 B.C. to the Present, New York : Free Press, 1989, ISBN 0-02-933151-X (free paperback, 2001, ISBN 0-02-933153-6)
 * The Training of Officers: From Military Professionalism to Irrelevance, New York : Free Press, 1990, ISBN 0-02-933152-8
 * The Transformation of War, New York : Free Press, 1991, ISBN 0-02-933155-2
 * Nuclear Proliferation and the Future of Conflict, New York : Free Press, 1993, ISBN 0-02-933156-0
 * Air Power and Maneuver Warfare, with contributions from Kenneth S. Brower and Steven L. Canby, Alabama : Air University Press, 1994, ISBN 1-58566-050-7
 * The Encyclopedia of Revolutions and Revolutionaries: From Anarchism to Zhou Enlai, New York : Facts on File, 1996, ISBN 0-8160-3236-X
 * The Sword and the Olive: A Critical History of the Israeli Defense Force, New York : Public Affairs, 1998, ISBN 1-891620-05-3
 * The Rise and Decline of the State, Cambridge University Press, 1999, ISBN 0-521-65629-X
 * The Art of War: War and Military Thought, London : Cassell, 2000, ISBN 0-304-35264-0 (also New York : Collins/Smithsonian, 2005, ISBN 0-06-083853-1)
 * Men, Women, and War, London : Cassell & Co., 2001, ISBN 0-304-35959-9
 * Moshe Dayan, London : Weidenfeld & Nicolson, 2004 ISBN 0-297-84669-8
 * Defending Israel: A Controversial Plan Toward Peace, New York : Thomas Dunne Books/St. Martin's Press, 2004, ISBN 0-312-32866-4
 * Countering Modern Terrorism: History, Current Issues, and Future Threats : Proceedings of the Second International Security Conference, Berlin, 15–17 December 2004, with Katharina von Knop and Heinrich Neisser, Bielefeld : Wbv, W. Bertelsmann Verlag, 2005, ISBN 3-7639-3309-3
 * The Changing Face of War: lessons of combat, from the Marne to Iraq, New York : Presidio Press, 2006, ISBN 978-0-89141-901-3
 * The Culture of War, New York: Presidio Press, 2008, ISBN 978-0-345-50540-8
 * The American Riddle (In Russian), Publisher: Irisen (Russia) 2008
 * The Land of Blood and Honey, New York : St. Martin's Press, 2010, ISBN 978-0-312-59678-1
 * The Age of Airpower, New York: Public Affairs, 2011, ISBN 978-1-58648-981-6
 * The Privileged Sex, North Charleston, SC : CreateSpace Independent Publishing Platform (On-Demand Publishing LLC), 2013, ISBN 978-1484983126
 * Wargames: From Gladiators to Gigabytes, Cambridge, Cambridge University Press, 2013, ISBN 978-1-107-03695-6
 * Conscience: A Biography, London, Reaktion, 2015, ISBN 978-1-78023-454-0
 * Equality: The Impossible Quest, Kouvola, Castalia House, 2015.
 * ''"Clio and Me" An Intellectual Autobiography, Kouvola, Castalia, House, 2015.
 * Pussycats: Why the Rest Keeps Beating the West—and What Can Be Done about It, CreateSpace, 2016.
 * Hitler in Hell, Castalia House, 2017.
 * More on War, Oxford University Press, 2017.

Selected articles

 * "Through a glass, darkly: some reflections on the future of war", Defense and the National Interest website, 2000
 * "Into the Abyss", Defense and the National Interest website, 2004
 * "Why Iraq will end as Vietnam did", LewRockwell.com, 18 November 2004
 * "Sharon on the warpath: Is Israel planning to attack Iran?", International Herald Tribune, 21 August 2004
 * "Costly withdrawal is the price to be paid for a foolish war", The Jewish Daily Forward, 25 November 2005
 * "Knowing why not to bomb Iran is half the battle", The Jewish Daily Forward, 20 April 2006

title: Martin van Creveld


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Photonics

Photonics is a branch of optics that involves the application of generation, detection, and manipulation of light in form of photons through emission, transmission, modulation, signal processing, switching, amplification, and sensing. Photonics is closely related to quantum electronics, where quantum electronics deals with the theoretical part of it while photonics deal with its engineering applications. Though covering all light's technical applications over the whole spectrum, most photonic applications are in the range of visible and near-infrared light. The term photonics developed as an outgrowth of the first practical semiconductor light emitters invented in the early 1960s and optical fibers developed in the 1970s.

History
The word 'Photonics' is derived from the Greek word "phos" meaning light (which has genitive case "photos" and in compound words the root "photo-" is used); it appeared in the late 1960s to describe a research field whose goal was to use light to perform functions that traditionally fell within the typical domain of electronics, such as telecommunications, information processing, etc.

An early instance of the word was in a December 1954 letter from John W. Campbell to Gotthard Gunther:"Incidentally, I’ve decided to invent a new science — photonics. It bears the same relationship to Optics that electronics does to electrical engineering. Photonics, like electronics, will deal with the individual units; optics and EE deal with the group-phenomena! And note that you can do things with electronics that are impossible in electrical engineering!"Photonics as a field began with the invention of the maser and laser in 1958 to 1960. Other developments followed: the laser diode in the 1970s, optical fibers for transmitting information, and the erbium-doped fiber amplifier. These inventions formed the basis for the telecommunications revolution of the late 20th century and provided the infrastructure for the Internet.

Though coined earlier, the term photonics came into common use in the 1980s as fiber-optic data transmission was adopted by telecommunications network operators. At that time, the term was used widely at Bell Laboratories. Its use was confirmed when the IEEE Lasers and Electro-Optics Society established an archival journal named Photonics Technology Letters at the end of the 1980s.

During the period leading up to the dot-com crash circa 2001, photonics was a field focused largely on optical telecommunications. However, photonics covers a huge range of science and technology applications, including laser manufacturing, biological and chemical sensing, medical diagnostics and therapy, display technology, and optical computing. Further growth of photonics is likely if current silicon photonics developments are successful.

Classical optics
Photonics is closely related to optics. Classical optics long preceded the discovery that light is quantized, when Albert Einstein famously explained the photoelectric effect in 1905. Optics tools include the refracting lens, the reflecting mirror, and various optical components and instruments developed throughout the 15th to 19th centuries. Key tenets of classical optics, such as Huygens Principle, developed in the 17th century, Maxwell's Equations and the wave equations, developed in the 19th, do not depend on quantum properties of light.

Modern optics
Photonics is related to quantum optics, optomechanics, electro-optics, optoelectronics and quantum electronics. However, each area has slightly different connotations by scientific and government communities and in the marketplace. Quantum optics often connotes fundamental research, whereas photonics is used to connote applied research and development.

The term photonics more specifically connotes:
 * The particle properties of light,
 * The potential of creating signal processing device technologies using photons,
 * The practical application of optics, and
 * An analogy to electronics.

The term optoelectronics connotes devices or circuits that comprise both electrical and optical functions, i.e., a thin-film semiconductor device. The term electro-optics came into earlier use and specifically encompasses nonlinear electrical-optical interactions applied, e.g., as bulk crystal modulators such as the Pockels cell, but also includes advanced imaging sensors.

An important aspect in the modern definition of Photonics is that there is not necessarily a widespread agreement in the perception of the field boundaries. Following a source on optics.org, the response of a query from the publisher of Journal of Optics: A Pure and Applied Physics to the editorial board regarding streamlining the name of the journal reported significant differences in the way the terms "optics" and "photonics" describe the subject area, with some description proposing that "photonics embraces optics". In practice, as the field evolves, evidences that "modern optics" and Photonics are often used interchangeably are very diffused and absorbed in the scientific jargon.

Emerging fields
Photonics also relates to the emerging science of quantum information and quantum optics. Other emerging fields include:

 * Optoacoustics or photoacoustic imaging where laser energy delivered into biological tissues will be absorbed and converted into heat, leading to ultrasonic emission.
 * Optomechanics, which involves the study of the interaction between light and mechanical vibrations of mesoscopic or macroscopic objects;
 * Optomics, in which devices integrate both photonic and atomic devices for applications such as precision timekeeping, navigation, and metrology;
 * Plasmonics, which studies the interaction between light and plasmons in dielectric and metallic structures. Plasmons are the quantizations of plasma oscillations; when coupled to an electromagnetic wave, they manifest as surface plasmon polaritons or localized surface plasmons.
 * Polaritonics, which differs from photonics in that the fundamental information carrier is a polariton. Polaritons are a mixture of photons and phonons, and operate in the range of frequencies from 300 gigahertz to approximately 10 terahertz.
 * Programmable photonics, which studies the development of photonic circuits that can be reprogrammed to implement different functions in the same fashion as an electronic FPGA

Applications

Applications of photonics are ubiquitous. Included are all areas from everyday life to the most advanced science, e.g. light detection, telecommunications, information processing, photovoltaics, photonic computing, lighting, metrology, spectroscopy, holography, medicine (surgery, vision correction, endoscopy, health monitoring), biophotonics, military technology, laser material processing, art diagnostics (involving InfraRed Reflectography, Xrays, UltraViolet fluorescence, XRF), agriculture, and robotics.

Just as applications of electronics have expanded dramatically since the first transistor was invented in 1948, the unique applications of photonics continue to emerge. Economically important applications for semiconductor photonic devices include optical data recording, fiber optic telecommunications, laser printing (based on xerography), displays, and optical pumping of high-power lasers. The potential applications of photonics are virtually unlimited and include chemical synthesis, medical diagnostics, on-chip data communication, sensors, laser defense, and fusion energy, to name several interesting additional examples.

 * Consumer equipment: barcode scanner, printer, CD/DVD/Blu-ray devices, remote control devices
 * Telecommunications: fiber-optic communications, optical down converter to microwave
 * Renewable Energy: Solar power systems
 * Medicine: correction of poor eyesight, laser surgery, surgical endoscopy, tattoo removal
 * Industrial manufacturing: the use of lasers for welding, drilling, cutting, and various methods of surface modification
 * Construction: laser leveling, laser rangefinding, smart structures
 * Aviation: photonic gyroscopes lacking mobile parts
 * Military: IR sensors, command and control, navigation, search and rescue, mine laying and detection
 * Entertainment: laser shows, beam effects, holographic art
 * Information processing
 * Passive daytime radiative cooling
 * Sensors: LIDAR, sensors for consumer electronics
 * Metrology: time and frequency measurements, rangefinding
 * Photonic computing: clock distribution and communication between computers, printed circuit boards, or within optoelectronic integrated circuits; in the future: quantum computing

Microphotonics and nanophotonics usually includes photonic crystals and solid state devices.

Overview of photonics research
The science of photonics includes investigation of the emission, transmission, amplification, detection, and modulation of light.

Light sources
Photonics commonly uses semiconductor-based light sources, such as light-emitting diodes (LEDs), superluminescent diodes, and lasers. Other light sources include single photon sources, fluorescent lamps, cathode ray tubes (CRTs), and plasma screens. Note that while CRTs, plasma screens, and organic light-emitting diode displays generate their own light, liquid crystal displays (LCDs) like TFT screens require a backlight of either cold cathode fluorescent lamps or, more often today, LEDs.

Characteristic for research on semiconductor light sources is the frequent use of III-V semiconductors instead of the classical semiconductors like silicon and germanium. This is due to the special properties of III-V semiconductors that allow for the implementation of light emitting devices. Examples for material systems used are gallium arsenide (GaAs) and aluminium gallium arsenide (AlGaAs) or other compound semiconductors. They are also used in conjunction with silicon to produce hybrid silicon lasers.

Transmission media
Light can be transmitted through any transparent medium. Glass fiber or plastic optical fiber can be used to guide the light along a desired path. In optical communications optical fibers allow for transmission distances of more than 100 km without amplification depending on the bit rate and modulation format used for transmission. A very advanced research topic within photonics is the investigation and fabrication of special structures and "materials" with engineered optical properties. These include photonic crystals, photonic crystal fibers and metamaterials.

Amplifiers
Optical amplifiers are used to amplify an optical signal. Optical amplifiers used in optical communications are erbium-doped fiber amplifiers, semiconductor optical amplifiers, Raman amplifiers and optical parametric amplifiers. A very advanced research topic on optical amplifiers is the research on quantum dot semiconductor optical amplifiers.

Detection
Photodetectors detect light. Photodetectors range from very fast photodiodes for communications applications over medium speed charge coupled devices (CCDs) for digital cameras to very slow solar cells that are used for energy harvesting from sunlight. There are also many other photodetectors based on thermal, chemical, quantum, photoelectric and other effects.

Modulation
Modulation of a light source is used to encode information on a light source. Modulation can be achieved by the light source directly. One of the simplest examples is to use a flashlight to send Morse code. Another method is to take the light from a light source and modulate it in an external optical modulator.

An additional topic covered by modulation research is the modulation format. On-off keying has been the commonly used modulation format in optical communications. In the last years more advanced modulation formats like phase-shift keying or even orthogonal frequency-division multiplexing have been investigated to counteract effects like dispersion that degrade the quality of the transmitted signal.

Photonic systems
Photonics also includes research on photonic systems. This term is often used for optical communication systems. This area of research focuses on the implementation of photonic systems like high speed photonic networks. This also includes research on optical regenerators, which improve optical signal quality.

Photonic integrated circuits
Photonic integrated circuits (PICs) are optically active integrated semiconductor photonic devices. The leading commercial application of PICs are optical transceivers for data center optical networks. PICs were fabricated on III-V indium phosphide semiconductor wafer substrates were the first to achieve commercial success; PICs based on silicon wafer substrates are now also a commercialized technology.

Key Applications for Integrated Photonics include:
 * Data Center Interconnects: Data centers continue to grow in scale as companies and institutions store and process more information in the cloud. With the increase in data center compute, the demands on data center networks correspondingly increase. Optical cables can support greater lane bandwidth at longer transmission distances than copper cables. For short-reach distances and up to 40 Gbit/s data transmission rates, non-integrated approaches such as vertical-cavity surface-emitting lasers can be used for optical transceivers on multi-mode optical fiber networks. Beyond this range and bandwidth, photonic integrated circuits are key to enable high-performance, low-cost optical transceivers.
 * Analog RF Signal Applications: Using the GHz precision signal processing of photonic integrated circuits, radiofrequency (RF) signals can be manipulated with high fidelity to add or drop multiple channels of radio, spread across an ultra-broadband frequency range. In addition, photonic integrated circuits can remove background noise from an RF signal with unprecedented precision, which will increase the signal to noise performance and make possible new benchmarks in low power performance. Taken together, this high precision processing enables us to now pack large amounts of information into ultra-long-distance radio communications.
 * Sensors: Photons can also be used to detect and differentiate the optical properties of materials. They can identify chemical or biochemical gases from air pollution, organic produce, and contaminants in the water. They can also be used to detect abnormalities in the blood, such as low glucose levels, and measure biometrics such as pulse rate. Photonic integrated circuits are being designed as comprehensive and ubiquitous sensors with glass/silicon, and embedded via high-volume production in various mobile devices. Mobile platform sensors are enabling us to more directly engage with practices that better protect the environment, monitor food supply and keep us healthy.
 * LIDAR and other phased array imaging: Arrays of PICs can take advantage of phase delays in the light reflected from objects with three-dimensional shapes to reconstruct 3D images, and Light Imaging, Detection and Ranging (LIDAR) with laser light can offer a complement to radar by providing precision imaging (with 3D information) at close distances. This new form of machine vision is having an immediate application in driverless cars to reduce collisions, and in biomedical imaging. Phased arrays can also be used for free-space communications and novel display technologies. Current versions of LIDAR predominantly rely on moving parts, making them large, slow, low resolution, costly, and prone to mechanical vibration and premature failure. Integrated photonics can realize LIDAR within a footprint the size of a postage stamp, scan without moving parts, and be produced in high volume at low cost.

Biophotonics
Biophotonics employs tools from the field of photonics to the study of biology. Biophotonics mainly focuses on improving medical diagnostic abilities (for example for cancer or infectious diseases) but can also be used for environmental or other applications. The main advantages of this approach are speed of analysis, non-invasive diagnostics, and the ability to work in-situ.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Photonics


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Mass (music)

The Mass (missa) is a form of sacred musical composition that sets the invariable portions of the Christian Eucharistic liturgy (principally that of the Catholic Church, the Anglican Communion, and Lutheranism), known as the Mass.

Most Masses are settings of the liturgy in Latin, the sacred language of the Catholic Church's Roman Rite, but there are a significant number written in the languages of non-Catholic countries where vernacular worship has long been the norm. For example, there have been many Masses written in English for a United States context since the Second Vatican Council, and others (often called "communion services") for the Church of England.

Masses can be a cappella, that is, without an independent accompaniment, or they can be accompanied by instrumental obbligatos up to and including a full orchestra. Many masses, especially later ones, were never intended to be performed during the celebration of an actual mass.

Middle Ages
The earliest musical settings of the mass are Gregorian chant. The different portions of the Ordinary came into the liturgy at different times, with the Kyrie probably being first (perhaps as early as the 7th century) and the Credo being last (it did not become part of the Roman mass until 1014).

In the early 14th century, composers began writing polyphonic versions of the sections of the Ordinary. The reason for this surge in interest is not known, but it has been suggested that there was a shortage of new music since composers were increasingly attracted to secular music, and overall interest in writing sacred music had entered a period of decline. The non-changing part of the mass, the Ordinary, then would have music which was available for performance all the time.

Two manuscripts from the 14th century, the Ivrea Codex and the Apt Codex, are the primary sources for polyphonic settings of the Ordinary. Stylistically, these settings are similar to both motets and secular music of the time, with a three-voice texture dominated by the highest part. Most of this music was written or assembled at the papal court at Avignon.

Several anonymous complete masses from the 14th century survive, including the Tournai Mass; however, discrepancies in style indicate that the movements of these masses were written by several composers and later compiled by scribes into a single set. The first complete mass we know of whose composer can be identified was the Messe de Nostre Dame (Mass of Our Lady) by Guillaume de Machaut in the 14th century.

Renaissance
The musical setting of the Ordinary of the mass was the principal large-scale form of the Renaissance. The earliest complete settings date from the 14th century, with the most famous example being the Messe de Nostre Dame of Guillaume de Machaut. Individual movements of the mass, and especially pairs of movements (such as Gloria–Credo pairs, or Sanctus–Agnus pairs), were commonly composed during the 14th and early 15th centuries. Complete masses by a single composer were the norm by the middle of the 15th century, and the form of the mass, with the possibilities for large-scale structure inherent in its multiple movement format, was the main focus of composers within the area of sacred music; it was not to be eclipsed until the motet and related forms became more popular in the first decades of the 16th century.

Most 15th-century masses were based on a cantus firmus, usually from a Gregorian chant, and most commonly put in the tenor voice. The cantus firmus sometimes appeared simultaneously in other voices, using a variety of contrapuntal techniques. Later in the century, composers such as Guillaume Dufay, Johannes Ockeghem, and Jacob Obrecht, used secular tunes for cantus firmi. This practice was accepted with little controversy until prohibited by the Council of Trent in 1562. In particular, the song L'homme armé has a long history with composers; more than 40 separate mass settings exist.

Other techniques for organizing the cyclic mass evolved by the beginning of the 16th century, including the paraphrase technique, in which the cantus firmus was elaborated and ornamented, and the parody technique, in which several voices of a polyphonic source, not just one, were incorporated into the texture of the mass. Paraphrase and parody supplanted cantus firmus as the techniques of choice in the 16th century: Palestrina alone wrote 51 parody masses.

Yet another technique used to organize the multiple movements of a mass was canon. The earliest masses based entirely on canon are Johannes Ockeghem's Missa prolationum, in which each movement is a prolation canon on a freely-composed tune, and the Missa L'homme armé of Guillaume Faugues, which is also entirely canonic but also uses the famous tune L'homme armé throughout. Pierre de La Rue wrote four separate canonic masses based on plainchant, and one of Josquin des Prez's mature masses, the Missa Ad fugam, is entirely canonic and free of borrowed material.

The Missa sine nomine, literally "Mass without a name", refers to a mass written on freely composed material. Sometimes these masses were named for other things, such as Palestrina's famous Missa Papae Marcelli, the Mass of Pope Marcellus, and many times they were canonic masses, as in Josquin's Missa sine nomine.

Many famous and influential masses were composed by Josquin des Prez, the single most influential composer of the middle Renaissance. At the end of the 16th century, prominent representatives of a cappella choral counterpoint included the Englishman William Byrd, the Castilian Tomás Luis de Victoria and the Roman Giovanni Pierluigi da Palestrina, whose Missa Papae Marcelli is sometimes credited with saving polyphony from the censure of the Council of Trent. By the time of Palestrina, however, most composers outside of Rome were using other forms for their primary creative outlet for expression in the realm of sacred music, principally the motet and the madrigale spirituale; composers such as the members of the Venetian School preferred the possibilities inherent in the new forms. Other composers, such as Orlande de Lassus, working in Munich and comfortably distant from the conservative influence of the Council of Trent, continued to write parody masses on secular songs. Monteverdi composed masses in stile antico, the Missa in illo tempore was published in 1610, one Messa a 4 da cappella in 1641 as part of Selva morale e spirituale along with single movements of the mass in stile concertato, another Messa a 4 da cappella was published after his death, in 1650.

Antoine Brumel composed a Missa Et ecce terrae motus with the employment of twelve voices,  Stefano Bernardi created masses for double choir for the balconies of the Salzburg Cathedral, such as the 1630 Missa primi toni octo vocum, when he was music director of the new building.

Baroque to Romantic (Catholic and Lutheran traditions)
The early Baroque era initiated stylistic changes which led to increasing disparity between masses written entirely in the traditional polyphonic manner (stile antico), whose principal advancements were the use of the basso continuo and the gradual adoption of a wider harmonic vocabulary, and the mass in modern style with solo voices and instrumental obbligatos. The Lutheran Michael Praetorius composed a mass for double choir in the old style, which he published in 1611 in the collection of church music for the mass in Latin, Missodia Sionia. Composers such as Henri Dumont (1610–1684) continued to compose plainsong settings, distinct from and more elaborate than the earlier Gregorian chants.

A further disparity arose between the festive missa solemnis and the missa brevis, a more compact setting. Composers like Johann Joseph Fux in the 18th century continued to cultivate the stile antico mass, which was suitable for use on weekdays and at times when orchestral masses were not practical or appropriate, and in 19th-century Germany the Cecilian movement kept the tradition alive. František Brixi, who worked at the Prague Cathedral, wrote his Missa aulica, a missa brevis in C, for four voices, trumpets, violin and continuo, "cantabile" but solo voices just singing short passages within chorale movements. The Italian style cultivated orchestral masses including soloists, chorus and obbligato instruments. It spread to the German-speaking Catholic countries north of the Alps, using instruments for color and creating dialogues between solo voices and chorus that was to become characteristic of the 18th-century Viennese style. The so-called "Neapolitan" or "cantata" mass style also had much influence on 18th-century mass composition, with its short sections set as self-contained solo arias and choruses in a variety of styles.

The 18th-century Viennese mass combines operatic elements from the cantata mass with a trend in the symphony and concerto to organize choral movements. The large scale masses of the first half of the century still have Glorias and Credos divided into many movements, unlike smaller masses for ordinary churches. Many of Mozart's masses are in missa brevis form, as are some of Haydn's early ones. Later masses, especially of Haydn, are of symphonic structure, with long sections divided into fewer movements, organized like a symphony, with soloists used as an ensemble rather than as individuals. The distinction between concert masses and those intended for liturgical use also came into play as the 19th century progressed.

After the Renaissance, the mass tended not to be the central genre for any one composer, yet among the most famous works of the Baroque, Classical, and Romantic periods are settings of the Ordinary of the Mass. Many of the famous masses of the Romantic era were Requiems, one of the most famous, A German Requiem by Brahms, being the composer's own selection of biblical texts rather than a setting of a standard liturgy.

20th and 21st century
By the end of the 19th century, composers were combining modern elements with the characteristics of Renaissance polyphony and plainchant, which continued to influence 20th-century composers, possibly fueled by the motu proprio Tra le sollecitudini (1903) of Pope Pius X. The revival of choral celebration of Holy Communion in the Anglican Church in the late 19th century marked the beginning several liturgical settings of mass texts in English, particularly for choir and organ. The movement for liturgical reform has resulted in revised forms of the mass, making it more functional by using a variety of accessible styles, popular or ethnic, and using new methods such as refrain and response to encourage congregational involvement. Nevertheless, the mass in its musical incarnation continues to thrive beyond the walls of the church, as is evident in many of the 21st-century masses listed here which were composed for concert performance rather than in service of the Roman Rite.

Musical reforms of Pius X
Pope Pius X initiated many regulations reforming the liturgical music of the mass in the early 20th century. He felt that some of the masses composed by the famous post-Renaissance composers were too long and often more appropriate for a theatrical rather than a church setting. He advocated primarily Gregorian plainchant and polyphony. He was primarily influenced by the work of the Abbey of Solesmes. Some of the rules he put forth include the following:
 * That any mass be composed in an integrated fashion, not by assembling different compositions for different parts.
 * That all percussive instruments should be forbidden.
 * That the piano be explicitly forbidden.
 * That the centuries' old practice of alternatim between choir and organ be concluded immediately.
 * That women must not be present in the choir.

These regulations carry little if any weight today, especially after the changes of the Second Vatican Council. Quite recently, Pope Benedict XVI has encouraged a return to chant as the primary music of the liturgy, as this is explicitly mentioned in the documents of the Second Vatican Council, specifically Sacrosanctum Concilium 116.

Post-Renaissance

 * Messa Concertata by Cavalli (1656)
 * Mass for double choir, from Missodia Sionia, by Michael Praetorius (1611)
 * 12 masses by Marc-Antoine Charpentier (including 3 Requiem + H.12, H.311), H.1, H.2, H.3, H.4, H.5, H.6, H.7, H.8, H.9, H.10, H.11, H.513.
 * Missa Scala Aretina by Francesc Valls (Barcelona, 1702)
 * Mass in B minor and four Missae by Johann Sebastian Bach
 * High Masses by Jan Dismas Zelenka
 * Requiem by Jean Gilles
 * Mass for double choir and double orchestra by Henri Desmarets
 * Requiem by André Campra 1723
 * Requiem by François-Joseph Gossec 1760
 * 18 masses by W. A. Mozart, including the Great Mass in C minor (1782) and Requiem (1791)
 * 14 masses by Joseph Haydn, including Nelson Mass and Mass in Time of War
 * Mass in C major and Missa Solemnis in D major by Ludwig van Beethoven
 * Mass in G major and 5 others by Franz Schubert
 * Missa Choralis and Hungarian Coronation Mass by Franz Liszt
 * Requiem by Hector Berlioz (1837)
 * Mass in D minor, Mass in E minor and Mass in F minor by Anton Bruckner
 * Requiem by Camille Saint-Saëns 1878
 * St. Cecilia Mass and 13 others by Charles Gounod
 * Messa by Giacomo Puccini
 * Petite messe solennelle (1863) by Gioachino Rossini
 * Mass in D minor, op. 10 (1866) by John Knowles Paine
 * Requiem by Gabriel Fauré
 * Requiem by Giuseppe Verdi
 * Mass in E♭, Op. 5 (1886) by Amy Beach
 * Requiem in B-flat minor (1890) by Antonín Dvořák
 * Mass in D major, Op. 86 (1887) by Antonín Dvořák
 * Mass in D by Ethel Smyth (1891)

20th century

 * Requiem by Maurice Duruflé
 * Mass in G by Francis Poulenc
 * Messe Solennelle by Jean Langlais
 * Glagolitic Mass (1926) by Leoš Janáček
 * Messe modale en septuor (1938) for soprano, alto, flute and string quartet by Jehan Alain
 * Mass in G minor by Ralph Vaughan Williams
 * Mass, Op. 130 (1945) for choir and brass by Joseph Jongen
 * Requiem by Bruno Maderna (1946)
 * Mass by Igor Stravinsky
 * Mass by Leonard Bernstein
 * Bộ lễ Seraphim (1960) by Paul Nguyễn Văn Hoà
 * War Requiem (1962) by Benjamin Britten
 * Mass for mixed chorus (1963) by Paul Hindemith
 * Requiem, for soprano and mezzo-soprano solo, mixed chorus and orchestra (1963–65) by György Ligeti
 * Missa supra Parsifal (1985) by Dimitri Aguero
 * Requiem (1990), Mass of the Children (2004), and Gloria by John Rutter
 * Requiem by Andrew Lloyd Webber
 * Mass in F minor by The Electric Prunes
 * Mass by David Maslanka
 * Mass Of The Sea, Op. 47 by Paul Patterson
 * Berliner Messe and Missa Syllabica by Arvo Pärt
 * Mass by Frank Martin
 * A Symphonic Mass by George Lloyd
 * Missa Laudate Pueri by Bertold Hummel
 * At Grace Cathedral, jazz mass by Vince Guaraldi
 * Mass To Hope by Dave Brubeck
 * Misa Criolla by Ariel Ramírez
 * Misa by Rodrigo Prats
 * New Plainsong Mass by David Hurd
 * Mass in Honor of St. Cecilia by Lou Harrison
 * African Sanctus by David Fanshawe
 * Polish Requiem by Krzysztof Penderecki
 * Missa Luba by Guido Haazen
 * Misa flamenca (1991) by Paco Peña
 * "Misatango" o "Misa a Buenos Aires" by Martín Palmieri (1996)

21st century

 * Missa Latina: pro Pace by Roberto Sierra
 * Missa Rigensis (2002) by Uģis Prauliņš
 * The Armed Man: A Mass for Peace by Karl Jenkins
 * Missa Concertante (2008) by Marcus Paus
 * Street Requiem (for those who have died on the street) for choir and orchestra by Kathleen McGuire, Jonathon Welch and Andy Payne (2014)
 * Missa Papae Francisci (2015) by Ennio Morricone
 * Missa Lucis, a jazz mass by Justin Binek

Masses written for the Anglican liturgy
These are more often known as 'Communion Services', and differ not only in that they are settings of English words, but also, as mentioned above, in that the Gloria usually forms the last movement. Sometimes the Kyrie movement takes the form of sung responses to the Ten Commandments, 1 to 9 being followed by the words 'Lord have mercy upon us and incline our hearts to keep this law', and the tenth by 'Lord have mercy upon us and write all these thy laws in our hearts, we beseech thee'. Since the texts of the 'Benedictus qui venit' and the 'Agnus Dei' do not actually feature in the liturgy of the 1662 Book of Common Prayer, these movements are often missing from some of the earlier Anglican settings. Charles Villiers Stanford composed a Benedictus and Agnus in the key of F major which was published separately to complete his service in C.

With reforms in the Anglican liturgy, the movements are now usually sung in the same order that they are in the Roman Catholic rite. Choral settings of the Creed, the most substantial movement, are nowadays rarely performed in Anglican cathedrals.

Well known Anglican settings of the mass, which may be found in the repertoire of many English cathedrals are:

 * Darke in F
 * Darke in E
 * Darke in A minor
 * Ireland in C
 * Stanford in C & F
 * Stanford in B flat
 * Stanford in A
 * Sumsion in F
 * Oldroyd, Mass of the Quiet Hour
 * Jackson in G
 * Howells, Collegium Regale
 * Leighton in D
 * Harwood in A flat
 * Wood in the Phrygian mode

title: Mass (music)


text:
Talk:Mass (music)

Stub question
I cheerfully concede this is more elaborate than most stubs, but it is indeed a stub that needs work. Feel free to add to it. Perhaps a list of notable composers of Masses, similar to the list I put at requiem, might be appropriate. ---User:Ihcoyc

I think the section Form of the Mass should be moved to Ordinary of the Mass. I think that's a more appropriate place for the full text to appear. Also, I think Sanctus and Benedictus are usually considered to be one part, not two. Alcuin 03:14, 13 January 2006 (UTC)

Placement of info
Is Rutter's Mass of the Children in the right place? It is in fact a missa brevis, as it has no credo section. ---User:Hesperus

Oh yes Hesperus you are correct..I agree with you 100%, that was such a delightful comment

Yes i'll second that agreement, no credo section is positively shocking, thank you for bringing that important comment to our attention Hesperus. No longer will I look at missa brevis's in the same light again.

I question the parenthesis of the filioque and thus am putting it fully into the text -- since Mass is a Western term, there is no reason to include the Eastern Orthodox caveat on the filioque.

Baroque to the present?
This is a huge period. Should we not split it up into subsections? Maybe Viennese Masses (Haydn & Co); Romantic/Operatic Masses (Gounod, Rheinberger et al.); 20th C Masses. Should a distiction be made between 'liturgical' masses and 'concert' masses? (Bach's Mass in B minor could never be used as part of the liturgy, for example)

Fiddleback 20:25, 13 April 2007 (UTC)

 * Yes: it should be subdivided and expanded greatly, in my opinion.  (I added a bunch to the pre-Baroque, but haven't edited the rest.)  Thanks!  Antandrus  (talk) 20:45, 13 April 2007 (UTC)

A lot of this is already in the Ordinary of the Mass article; I think it belongs here.Sparafucil 05:53, 8 June 2007 (UTC)

History sections
I have added two sections concerning the history of the mass from Baroque through Romantic and 20th and 21st century in addition to the lists already in the article. Feel free to add or amend! Aprickel (talk) 01:39, 16 December 2009 (UTC)Aprickel

Requiem mass
I see several examples of a Requiem mass listed, but think they should go to the special article. --Gerda Arendt (talk) 11:11, 8 January 2013 (UTC)

"a cappella" vs. "unaccompanied"
There seems to be disagreement whether "a cappella" or "unaccompanied" should be used. If this article is supposed to approach scholarly quality on this topic, then the term "unaccompanied" is the correct term. To put it succinctly, I quote this paragraph from Grove's Dictionary of Music and Musicians:

 * Normally, choral music sung without instrumental accompaniment. Originally (c1600) the term was used to distinguish works composed in the older polyphonic style of the Renaissance from those written in the newer concertato style of the early Baroque. During the 19th century the Roman Catholic Church idealized 16th-century polyphony and the works of Palestrina in particular. Noting that no instrumental parts were included in the sources containing this music, and unaware that instruments were often used during the Renaissance to double or substitute for vocal parts, musicians came to believe that a cappella referred to unaccompanied choral singing (see Chorus (i), §4). Since that time, the term has become synonymous with "unaccompanied singing", both religious and secular. (emph. added)

Although the use of the term a cappella for unaccompanied vocal music is the vernacular (of which I have no problem and use myself), in this article "unaccompanied" is more accurate. Especially considering that we are using the words "can be accompanied," the use of "unaccompanied" is better suited. — Preceding unsigned comment added by B0cean (talk • contribs) 02:11, 29 January 2013 (UTC)

 * The foregoing is correct. Historically "a cappella" was used for a style that was liturgically appropriate.  It would not have been used of the madrigal, for example, which was often unaccompanied, but not liturgical music. In today's vernacular, unaccompanied madrigals are commonly described as "a cappella," in contravention of its historical meaning.  — Preceding unsigned comment added by Fugueman (talk • contribs) 02:41, 29 January 2013 (UTC)

 * This is all covered, appropriately enough, in the blue linked A cappella article. This article's lead currently distinguishes a cappella style from orchestral masses (a fair chunk of the concert repertoire). If a 3-fold division is felt useful, it could be reworded thus: "Masses can be a cappella, that is,either unaccompanied or without an independent accompaniment, or they can be accompanied by..." Sparafucil (talk) 22:30, 29 January 2013 (UTC)

"Missae breves"
Should we mention this is the plural form of "Missa Brevis" when we use this? This isn't apparent for everyone. --Ahyangyi (talk) 15:36, 29 April 2014 (UTC)

Merge Missa brevis in?
Per suggestion here

I'm rather indifferent on such merge proposal, the more important point being that the current content of Missa brevis needs some serious updating: whether that is done before or after (or without) a merge is secondary imho (I can live with both a merge and a no-merge option), but a higher quality of the content is something I see as a first objective. --Francis Schonken (talk) 11:17, 29 November 2014 (UTC)

 * You misunderstood my proposal: I suggested to have one article Missa (music) covering the many meanings in which the term Missa is used in music, and several special meanings such as Missa brevis, Missa solemnis etc. It is difficult to improve the quality of Missa brevis as long as there are types of the mass covered which are not usually named "brevis", such as Missa as Bach understood it (Kyrie and Gloria) or a mass intentionally without Gloria for Lent. - By just translating Missa to mass we would loose recognisability, - you see Missa on many title pages, not mass. --Gerda Arendt (talk) 11:58, 29 November 2014 (UTC)
 * Hoboken XXII:9 (containing all five "Ordinarium" parts of the tridentine mass) = Missa in tempore belli = Mass in Time of War = Paukenmesse = Kettledrum Mass. May I suggest that your confusion probably originates from WP:OR on this frontispiece: File:BWV 232 Titelblatt Missa.jpg (which is all in all a quite exceptional case, not normative in its time, nor before, nor afterwards)? --Francis Schonken (talk) 12:17, 29 November 2014 (UTC)
 * I look at this, for example. Many composers of different nationalities called a mass Missa and marked a movement Allegro, both internationally understood. I think Wikipedia should have room for that. We don't substitute Allegro by "fast" or (better) "joyful". - You can of course go ahead with your proposal, but please don't say that it was my idea. --Gerda Arendt (talk) 12:36, 29 November 2014 (UTC)
 * Non-argument. Some terms are always translated, some are often translated, others are sometimes translated, some are almost never or never translated. Missa is the latin word for Mass. Note that the Carus Verlag page you linked to (on Johann Michael Haydn's Missa Tempore Quadragesimae) indicates "Masses" as genre for the work. Missa is not a different "genre" from "Mass". All masses with five, four, three of two Ordinarium parts can be indicated as "Missa" or as "Mass", the same way as a Masses "Credo" can be called "Nicene Creed" in English ("Nicene" while that is the usual version in tridentine mass). Depends on author whether it is translated or not. --Francis Schonken (talk) 13:03, 29 November 2014 (UTC)
 * FYI, some composers have translated tempo indicators, e.g. Adagio into "Langsam" (Mahler, 7th symphony). --Francis Schonken (talk) 13:18, 29 November 2014 (UTC)
 * Perhaps I misunderstand. Is "Missa brevis" a genre? Is it worth explaining even if not? Same for Missa. Some composers have tempo and other markings in their native language, - that isn't what I talked about. I said that IF a composer marks Allegro, we don't go and translate it. - In case you went for including the various types of Missa here, how would a lead look like, with many bolded redirects? --Gerda Arendt (talk) 13:31, 29 November 2014 (UTC)
 * "Missa brevis" is a mixed bag concept, depends on which meaning(s) is/are taken out of the bag. Some authors have argued that "Missa brevis et solemnis" is a separate genre that applies to the kind of masses Colloredo made Mozart write. Missa brevis is latin for "short Mass", so much is sure, but it has several meanings, some of which are a genre, some are not. --Francis Schonken (talk) 13:52, 29 November 2014 (UTC)
 * ...so I come back to the first argument I made in this section: the Missa brevis article content needs some serious updating, while it sheds a lot of unclarity... yes, the many meanings of Missa brevis are messy, no excuse though to write an article that leaves readers unclear... --Francis Schonken (talk) 14:11, 29 November 2014 (UTC)
 * I found Missa brevis like this in 2010, and expressed the wish for "Missa" then already, --Gerda Arendt (talk) 14:28, 29 November 2014 (UTC)
 * I see no relevance in those remarks: say what you have to say, without innuendo please. --Francis Schonken (talk) 16:24, 29 November 2014 (UTC)
 * (e.c.) Another example that translation has little to do with this (sometimes symphony/sinfonia is translated, sometimes it is not, says little about its meaning):
 * Eine Alpensinfonie (arguably rather a tone poem than a symphony) usually translated in English → An Alpine Symphony
 * Sinfonia domestica (by the same composer, also arguably rather a tone poem than a sinfonia or symphony) usually not translated — although, as in Wikipedia, for this title the Italian term "sinfonia" is sometimes translated in latinized Greek (sic) "symphonia".
 * Also the Petite messe solennelle can be called a Mass or Missa, while it contains a setting of all five "Ordinarium" parts, in Latin. --Francis Schonken (talk) 13:52, 29 November 2014 (UTC)
 * Why would you call it Missa if the composer called it messe? - Btw, I was told that you can't say "a Mass", only "a mass" (I think by Tony1). --Gerda Arendt (talk) 14:28, 29 November 2014 (UTC)
 * Why would one call a tone poem a "Sinfonie" or a "sinfonia"? Why would one translate either of those in English (symphony) or latinized Greek (symphonia)? Rhetorical questions: the why question is of little consequence here. The fact is: it is done sometimes or often depending on the case.
 * Another example: why would one translate Glagolská mše or Mša glagolskaja into Missa Glagolitica or Glagolitic Mass? I don't know why it happens, but it happens. --Francis Schonken (talk) 14:47, 29 November 2014 (UTC)
 * Good answers to not my question. I didn't ask why translate to mass (English). I asked why translate to Missa, French to Latin that is. --Gerda Arendt (talk) 14:50, 29 November 2014 (UTC)
 * Missa Glagolitica is the better example (Czech to Latin translation). --Francis Schonken (talk) 15:10, 29 November 2014 (UTC)
 * Here's "messe" translated into "Missa" for Rossini's petite solennelle (in an English-language publication) —— Why? I have no clue. --Francis Schonken (talk) 15:16, 29 November 2014 (UTC)

Returning to Gerda's original question (which I initially misunderstood, my bad): Should Missa brevis be moved to Missa (music)? No, Missa (music) should redirect to Mass (music), unless someone can demonstrate that in the context of music "Mass" and "Missa" have generally accepted divergent meanings. I.e.: not a part of the sources giving different meanings (like for Missa brevis), which should be explained in a single article, but widely accepted divergent meanings. That is not the case. Note that I saw a lot of sources when straightening out the list of Mozart Masses: while many of these gave a different interpretation to Missa brevis and the like, none of them indicated "Missa" would not be a synonym to "Mass". Same for the sources I saw when working on the Mass for the Dresden court article. Some would avoid the ambiguous "Missa brevis" qualification altogether (using "Kyrie–Gloria Missa" or whatever), but none of them indicated that Missa would not be a synonym to "Mass". --Francis Schonken (talk) 17:06, 29 November 2014 (UTC)
 * Fine. --Gerda Arendt (talk) 18:23, 29 November 2014 (UTC)
 * I'm about to remove the merge suggestion templates I posted yesterday at Mass (music) and Missa brevis. I suppose there's no objection to that then? --Francis Schonken (talk) 09:03, 30 November 2014 (UTC)
 * With the re-arranged and expanded content of Mass (music) (and other updates that occured before that) I think some major steps in updating (as suggested above) are completed, and the merge suggestion templates can now be removed. --Francis Schonken (talk) 12:51, 29 January 2015 (UTC)

Addition and need for clarifictions

 * Mass of the Children and Colin Mawby's Bonifaius-Messe are also examples of additional text.
 * What does the header "other denominations" mean when the lead names Catholic, Anglican and Lutheran? --Gerda Arendt (talk) 14:47, 29 November 2014 (UTC)
 * Re. other examples with parts outside the ordinarium: a few representative examples would be good in the article, yes.
 * "Other denominations" refers to "other than the denomination that uses the Tridentine Mass", i.e. the Roman Catholic domination. Yes, can be clarified a bit while "tridentine" may be less common to many readers.
 * On the whole, most of this article refers to mass compositions that fit in (the mindframe of) the Tridentine Mass ritual (hence Ordinarium/Proprium etc.) — which also means a lot is still missing from the article, somewhat more on Deutsche Messe compositions, Eastern Orthodox mass music (e.g. Liturgy of St. John Chrysostom compositions) etc, etc, should be added. --Francis Schonken (talk) 15:22, 29 November 2014 (UTC)
 * The lead, before going to Tridentine, says "the invariable portions of the Eucharistic liturgy (principally that of the Catholic Church, the Anglican Communion, and Lutheranism)". I would expect those in more detail in the body, which for Lutheranism might lead to discussing Kyrie+Gloria Missa (which I didn't invent), sometimes (not precisely) named Lutherische Messe. --Gerda Arendt (talk) 15:26, 29 November 2014 (UTC)
 * Useful suggestions, that can be explored. I would add to that: the lead must be rewritten, its current interpretation of the subject of the article is, to say the least, a little bit POV. --Francis Schonken (talk) 15:32, 29 November 2014 (UTC)
 * Ideas as they come: The Armed Man, --Gerda Arendt (talk) 18:26, 29 November 2014 (UTC)
 * Also requiem masses: Britten's War Requiem --Francis Schonken (talk) 18:40, 29 November 2014 (UTC)

Sort and scope of list
Trying to insert a mass, I see that I would not know to insert where because the arrangement follows no system that is recognizable by me.
 * Why are Requiem masses listed here at all, which are also in the relevant article? - A link would do. - Btw: The Requiem article used to be Requiem (music), which seems more general and therefore more appropriate for works which are not "for the Requiem Mass", - some are for concert, some don't even use the liturgical text.
 * We could go by composer (alpha), - perhaps easiest to find, or by year of composition, or by year of composer's birth ... - we could also make a sortable table, - just ideas. --Gerda Arendt (talk) 19:54, 30 April 2015 (UTC)
 * This article isn't a list: a few relevant examples are welcome per topic/period/section, that's all. If you want a list, it is possible to start one (compare List of Magnificat composers, sortable in various ways). --Francis Schonken (talk) 10:07, 1 May 2015 (UTC)
 * Or something like Liste von Messen, translated in English (although I'd prefer a sortable table). --Francis Schonken (talk) 10:42, 1 May 2015 (UTC)
 * The table at List of symphonies with names is close to the format I'd prefer for such list. --Francis Schonken (talk) 10:59, 1 May 2015 (UTC)
 * A sortable: Zukunftsmusik, - I am busy with articles at present. - For now: I suggest to remove all Requiem masses and need to know how this listing (is that a better word?) should be sorted. --Gerda Arendt (talk) 11:04, 1 May 2015 (UTC)
 * Representative Requiems should not be removed. --Francis Schonken (talk) 11:12, 1 May 2015 (UTC)

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External links modified (January 2018)
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missa tota
I followed a link in another article (Mass in B Minor) to missa tota. This redirected me to the current article ("Redirected from Missa Tota"). However the current article has no mention of missa tota. Missa tota is discussed in the article titled missa brevis. I think that the missa tota redirect should be changed to refer to the missa brevis article instead. I'd do it myself, except that I don't know how to edit redirects. Omc (talk) 18:28, 4 February 2023 (UTC)

 * Done. --  Jack of Oz   [pleasantries]  19:18, 4 February 2023 (UTC)

Mass proper (vs. Mass ordinary)
some composers specifically wrote settings of the Catholic Liturgical Mass that were written as settings of the text as it would be spoken on holidays, and/or combined with an offertorium (mass ordinary vs mass proper). Not sure this distinction- settings of the text of the Ordinary vs. "Mass Proper"s (if I have the term vaguely right even after a reminder from a Google Search) - is important enough for the article, but thought I'd bring it up... ELSchissel (talk) 18:20, 10 August 2023 (UTC) (Edit: also called missa propria, e.g., I think.)

title: Talk:Mass (music)


text:
June Foray

June Foray (born June Lucille Forer; September 18, 1917 – July 26, 2017) was an American voice actress and radio personality, best known as the voice of such animated characters as Rocky the Flying Squirrel, Natasha Fatale, Nell Fenwick, Lucifer from Disney's Cinderella, Cindy Lou Who, Jokey Smurf, Granny from the Warner Bros. cartoons directed by Friz Freleng, Grammi Gummi from Disney's Adventures of the Gummi Bears series, and Magica De Spell, among many others.

Her career encompassed radio, theatrical shorts, feature films, television, records (particularly with Stan Freberg), video games, talking toys, and other media. Foray was also one of the early members of ASIFA-Hollywood, the society devoted to promoting and encouraging animation. She is credited with the establishment of the Annie Awards, as well as being instrumental in the creation of the Academy Award for Best Animated Feature in 2001. She has a star on the Hollywood Walk of Fame honoring her voice work in television.

Chuck Jones was quoted as saying: "June Foray is not the female Mel Blanc. Mel Blanc was the male June Foray."

Early life
June Lucille Forer was born on September 18, 1917, in Springfield, Massachusetts, one of three children of Ida (Robinson) and Morris Forer. Her mother was of Lithuanian Jewish and French Canadian ancestry, and her father was a Jewish emigrant from Odessa, Russian Empire. The family resided at 75 Orange Street, Forest Park. As a small child, Foray first wanted to be a dancer, so her mother sent her to local classes, but she had to drop out due to a case of pneumonia. Her voice was first broadcast in a local radio drama when she was 12 years old; by age 15, she was doing regular radio voice work.

Two years later, after graduating from Classical High School, she moved with her parents and siblings to live in Los Angeles, near Ida's brother, after Morris Forer, an engineer, fell on hard financial times.

Acting career
After entering radio through the WBZA Players, Foray starred in her own radio series Lady Make Believe in the late 1930s. She soon became a popular voice actress, with regular appearances on coast-to-coast network shows including Lux Radio Theatre and The Jimmy Durante Show.

In the 1940s, Foray also began film work, including a few roles in live action movies, but mostly did voice over work for animated cartoons and radio programs and occasionally dubbing films and television. On radio, Foray did the voices of Midnight the Cat and Old Grandie the Piano on The Buster Brown Program, which starred Smilin' Ed McConnell, from 1944 to 1952. She later did voices on the Mutual Broadcasting System program Smile Time for Steve Allen. Her work in radio ultimately led her to recording for a number of children's albums for Capitol Records.

For Walt Disney, Foray voiced Lucifer the Cat in the feature film Cinderella, Lambert's mother in Lambert the Sheepish Lion, a mermaid in Peter Pan and Witch Hazel in the Donald Duck short Trick or Treat. Decades later, Foray was the voice of Grandmother Fa in the 1998 animated Disney film Mulan. She also did a variety of voices in Walter Lantz Productions' Woody Woodpecker cartoons, including Woody's nephew and niece, Knothead and Splinter. Impressed by her performance as Witch Hazel, in 1954 Chuck Jones invited her over to Warner Brothers Cartoons. For Warner Brothers, she was Granny (whom she had played on vinyl records starting in 1950, before officially voicing her in Red Riding Hoodwinked, released in 1955, taking over for Bea Benaderet), owner of Tweety and Sylvester, and a series of witches, including Looney Tunes' own Witch Hazel, with Jones as director. Like most of Warner Brothers' voice actors at the time (with the exception of Mel Blanc), Foray was not credited for her roles in these cartoons. She played Bubbles on The Super 6 and Cindy Lou Who, asking "Santa" why he's taking their tree, in How the Grinch Stole Christmas. In 1960, she provided the speech for Mattel's original "Chatty Cathy" doll; capitalizing on this, Foray also voiced the malevolent "Talky Tina" doll in the Twilight Zone episode "Living Doll", first aired on November 1, 1963. Foray worked for Hanna-Barbera, including on Scooby-Doo, Where Are You!, The Jetsons, The Flintstones and many other shows. In 1959, she auditioned for the part of Betty Rubble on The Flintstones and voiced the character in the original pilot episode, opposite Mel Blanc who voiced Betty's husband, Barney Rubble, but Bea Benaderet was eventually cast in the role; Foray described herself as "terribly disappointed" at not getting to play Betty. Foray eventually made a guest appearance on The Flintstones as the voice of Granny Hatrock in the episode "The Bedrock Hillbillies".

She did extensive voice acting for Stan Freberg's commercials, albums, and 1957 radio series, memorably as secretary to the werewolf advertising executive. She also appeared in several Rankin/Bass TV specials in the 1960s and 1970s, voicing the young Karen and the teacher in the TV special Frosty the Snowman (although only her Karen singing parts remained in later airings, after Rankin-Bass re-edited the special a few years after it debuted, with Foray's dialogue re-dubbed by an uncredited child actress, Suzanne Davidson). She voiced all the female roles in Rikki-Tikki-Tavi (1975), including the villainous cobra Nagaina. She played multiple characters on The Rocky and Bullwinkle Show, including Natasha Fatale and Nell Fenwick, as well as male lead character Rocket J. Squirrel (a.k.a. Rocky Squirrel) for Jay Ward, and played Ursula on George of the Jungle; and also starred on Fractured Flickers.

In the mid-1960s, she became devoted to the preservation and promotion of animation and wrote numerous magazine articles about animation. She and a number of other animation artists had informal meetings around Hollywood in the 1960s, and later decided to formalize this as ASIFA-Hollywood, a chapter of the Association Internationale du Film d'Animation (the International Animated Film Association). She is credited with coming up with the idea of the Annie Awards in 1972, awarded by ASIFA-Hollywood, having noted that there had been no awards to celebrate the field of animation. In 1988, she was awarded the Bob Clampett Humanitarian Award. In 1995, ASIFA-Hollywood established the June Foray Award, which is awarded to "individuals who have made a significant and benevolent or charitable impact on the art and industry of animation". Foray was the first recipient of the award. She was an enthusiastic member of the Los Angeles Student Film Institute advisory board and frequent host and/or presenter at its annual festivals. In 2007, Foray became a contributor to ASIFA-Hollywood's Animation Archive Project. She also had sat on the Governors' board for the Academy of Motion Picture Arts & Sciences and lobbied for two decades for the academy to establish an Academy Award for animation; the academy created the Academy Award for Best Animated Feature in 2001 from her petitioning.

In 2007, Britt Irvin became the first person ever to voice a character in a cartoon remake that had been previously played by Foray in the original series when she voiced Ursula in the new George of the Jungle series on Cartoon Network. In 2011, Roz Ryan voiced Witch Lezah (Hazel spelled backwards) in The Looney Tunes Show, opposite June Foray as Granny. Foray also voiced May Parker in Spider-Man and His Amazing Friends (1981–83), as well as Raggedy Ann on several TV movies, Grandma Howard on Teen Wolf, Jokey Smurf and Mother Nature on The Smurfs, and Magica De Spell and Ma Beagle in DuckTales. At the same time, she had a leading role voicing Grammi Gummi on Disney's Adventures of the Gummi Bears, an animated series credited with kickstarting an era of dramatically increased artistic standards for television animation, working with her Rocky and Bullwinkle co-star Bill Scott until his death in 1985.

Foray guest starred only once on The Simpsons, in the season one episode "Some Enchanted Evening", as the receptionist for the Rubber Baby Buggy Bumper Babysitting Service. This was a play on a Rocky & Bullwinkle gag years earlier in which none of the cartoon's characters, including narrator William Conrad, were able to pronounce "rubber baby buggy bumpers" unerringly. Foray was later homaged by The Simpsons, in the season eight episode "The Itchy & Scratchy & Poochie Show", in which the character June Bellamy (voiced by Tress MacNeille) is introduced as the voice behind both Itchy and Scratchy. According to The Simpsons writer and producer Mike Reiss, Foray voiced a few parts at the first table read for The Simpsons in early 1989 "but she sounded too cartoony for our show".

Foray appeared on camera in a major role only once, in Sabaka, as the high priestess of a fire cult. She also appeared on camera in an episode of Green Acres as a Mexican telephone operator. In 1991, she provided her voice as the sock-puppet talk-show host Scary Mary on an episode of Married... with Children. She had a cameo role in Boris & Natasha (1992), but once again played Rocky and Natasha throughout the feature film The Adventures of Rocky and Bullwinkle (2000). Another on-camera appearance was as herself on an episode of the 1984 TV sitcom The Duck Factory.

She was also often called in for ADR voice work for television and feature films. This work included dubbing the voice of Mary Badham in Twilight Zone episode "The Bewitchin' Pool" and the voices for Sean and Michael Brody in some scenes of the film Jaws. She dubbed several people in Bells Are Ringing, Diana Rigg in some scenes of The Hospital, Robert Blake in drag in an episode of Baretta and a little boy in The Comic.

Later career
In 1996 and 1997, Foray won the Annie Award for Outstanding Individual Achievement for Voice Acting by a Female Performer in an Animated Television Production for her work in Sylvester and Tweety Mysteries. In 2000, Foray returned to play Rocky the Flying Squirrel in Universal Pictures' live-action/CGI animated film The Adventures of Rocky and Bullwinkle, co-starring and produced by Robert De Niro. On Season Three, Episode One ("The Thin White Line") of Family Guy, Foray again played Rocky in a visual gag with a single line ("And now, here's something we hope you'll really like!"). Foray voiced the wife of the man getting dunked ("Don't tell him, Carlos!") in Pirates of the Caribbean. In 2003, she guest starred as the villain Madame Argentina in the Powerpuff Girls episode, "I See a Funny Cartoon in Your Future". During this time, Foray also had a regular role, reprising Granny on Baby Looney Tunes and also Witch Hazel in an episode of another Warner Bros. Animation series Duck Dodgers. In October 2006, she portrayed Susan B. Anthony on three episodes of the podcast The Radio Adventures of Dr. Floyd. In November 2009, Foray appeared twice on The Marvelous Misadventures of Flapjack: in one episode as Ruth, a pie-maker trapped in Bubbie's stomach, and in another episode as Kelly, a young boy having a birthday party and as Kelly's Mom and Captain K'Nuckles' kindergarten teacher.

In 2011, she reprised her role as Granny in Cartoon Network's The Looney Tunes Show, which was her last regular gig. That year, she received the Comic-Con Icon Award at the 2011 Scream Awards. She also appeared as Granny in the theatrically released Looney Tunes short, I Tawt I Taw a Puddy Tat, which was shortlisted for Academy Award consideration.

In 2012, Foray received her first Emmy nomination and won in the category of Outstanding Performer in an Animated Program for her role as Mrs. Cauldron on The Garfield Show. She thus became, at age 94, the oldest entertainer to be nominated for, and to win, an Emmy Award. She reprised her role of Rocky in a Rocky and Bullwinkle short film, which was released in 2014.

In September 2013, she was honored with the Governors Award at the 65th Primetime Creative Arts Emmy Awards. That same year, she reprised her role as Magica De Spell in the video game DuckTales: Remastered.

Personal life
Foray married Bernard Barondess in 1941. The marriage ended in divorce. She met Hobart Donovan while appearing on The Buster Brown Program on radio. He was the show's main writer and had also written The Buster Brown comic book. Foray and Donovan were married from 1955 until Donovan's death in 1976. She had no children by either marriage.

In 1973, Foray was an organizer of a meat boycott in response to President Nixon's freezing of meat (and other) prices. As a result of this, Foray was included in the Master list of Nixon's political opponents, commonly known as Nixon's Enemies List.

Death
Foray died at a hospital in Los Angeles, California, on July 26, 2017, at the age of 99. She had been in declining health since an automobile accident in 2015.

title: June Foray


text:
Ernest Picard

Louis Joseph Ernest Picard (24 December 1821 – 13 May 1877) was a French politician.

Life
Louis Joseph Ernest Picard was born in Paris. After taking his doctorate in law in 1846 he joined the Parisian bar. Elected to the corps législatif in 1858, he became a follower of Émile Ollivier. As Ollivier moved towards the government standpoint, Picard, one of the members of the group known as Les Cinq, veered more to the left.

In the 1860s Picard was an active member of the Conférence Molé, as were Léon Gambetta, Clément Laurier and Léon Renault. At that time the Molé met in the Café Procope in the Rue de l'Ancienne-Comédie, the oldest coffee house in Paris.

In 1868 he founded a weekly democratic journal, L'Electeur libre, and in 1869 was elected both for Hérault and Paris, electing to sit for the former. From 4 September 1870 he held the portfolio of finance in the government of National Defence. In January 1871 he accompanied Jules Favre to Versailles to arrange the capitulation of Paris, and the next month he became minister of the interior in Adolphe Thiers's cabinet.

Attacked both by the monarchist and the republican press, he resigned in May. Later in the year he was sent as ambassador to Brussels, where he remained for two years. On his return to Paris he resumed his seat in the Left centre, and in 1875 became life senator. He died in Paris.

title: Ernest Picard


text:
Little's law

In mathematical queueing theory, Little's law (also result, theorem, lemma, or formula ) is a theorem by John Little which states that the long-term average number L of customers in a stationary system is equal to the long-term average effective arrival rate λ multiplied by the average time W that a customer spends in the system. Expressed algebraically the law is

 * $$ L = \lambda W. $$

The relationship is not influenced by the arrival process distribution, the service distribution, the service order, or practically anything else. In most queuing systems, service time is the bottleneck that creates the queue.

The result applies to any system, and particularly, it applies to systems within systems. For example in a bank branch, the customer line might be one subsystem, and each of the tellers another subsystem, and Little's result could be applied to each one, as well as the whole thing. ; this rules out transition states such as initial startup or shutdown.

In some cases it is possible not only to mathematically relate the average number in the system to the average wait but even to relate the entire probability distribution (and moments) of the number in the system to the wait.

History
In a 1954 paper Little's law was assumed true and used without proof. The form L = λW was first published by Philip M. Morse where he challenged readers to find a situation where the relationship did not hold. Little published in 1961 his proof of the law, showing that no such situation existed. Little's proof was followed by a simpler version by Jewell and another by Eilon. Shaler Stidham published a different and more intuitive proof in 1972.

Finding response time
Imagine an application that had no easy way to measure response time. If the mean number in the system and the throughput are known, the average response time can be found using Little’s Law:

 * mean response time = mean number in system / mean throughput

For example: A queue depth meter shows an average of nine jobs waiting to be serviced. Add one for the job being serviced, so there is an average of ten jobs in the system. Another meter shows a mean throughput of 50 per second. The mean response time is calculated as 0.2 seconds = 10 / 50 per second.

Customers in the store
Imagine a small store with a single counter and an area for browsing, where only one person can be at the counter at a time, and no one leaves without buying something. So the system is:

 * entrance → browsing → counter → exit

If the rate at which people enter the store (called the arrival rate) is the rate at which they exit (called the exit rate), the system is stable. By contrast, an arrival rate exceeding an exit rate would represent an unstable system, where the number of waiting customers in the store would gradually increase towards infinity.

Little's Law tells us that the average number of customers in the store L, is the effective arrival rate λ, times the average time that a customer spends in the store W, or simply:

 * $$L = \lambda W $$

Assume customers arrive at the rate of 10 per hour and stay an average of 0.5 hour. This means we should find the average number of customers in the store at any time to be 5.
 * $$L = 10 \times 0.5 = 5 $$

Now suppose the store is considering doing more advertising to raise the arrival rate to 20 per hour. The store must either be prepared to host an average of 10 occupants or must reduce the time each customer spends in the store to 0.25 hour. The store might achieve the latter by ringing up the bill faster or by adding more counters.

We can apply Little's Law to systems within the store. For example, consider the counter and its queue. Assume we notice that there are on average 2 customers in the queue and at the counter. We know the arrival rate is 10 per hour, so customers must be spending 0.2 hours on average checking out.
 * $$W =\frac{L}{\lambda} = \frac{2}{10} = 0.2 $$

We can even apply Little's Law to the counter itself. The average number of people at the counter would be in the range (0, 1) since no more than one person can be at the counter at a time. In that case, the average number of people at the counter is also known as the utilisation of the counter.

However, because a store in reality generally has a limited amount of space, it can eventually become unstable. If the arrival rate is much greater than the exit rate, the store will eventually start to overflow, and thus any new arriving customers will simply be rejected (and forced to go somewhere else or try again later) until there is once again free space available in the store. This is also the difference between the arrival rate and the effective arrival rate, where the arrival rate roughly corresponds to the rate at which customers arrive at the store, whereas the effective arrival rate corresponds to the rate at which customers enter the store. However, in a system with an infinite size and no loss, the two are equal.

Estimating parameters
To use Little's law on data, formulas must be used to estimate the parameters, as the result does not necessarily directly apply over finite time intervals, due to problems like how to log customers already present at the start of the logging interval and those who have not yet departed when logging stops.

Applications
Little's law is widely used in manufacturing to predict lead time based on the production rate and the amount of work-in-process.

Software-performance testers have used Little's law to ensure that the observed performance results are not due to bottlenecks imposed by the testing apparatus.

Other applications include staffing emergency departments in hospitals.

Distributional form
An extension of Little's law provides a relationship between the steady state distribution of number of customers in the system and time spent in the system under a first come, first served service discipline.

title: Little's law