title: Microorganism

text: Antonie van Leeuwenhoek is considered to be one of the fathers of microbiology. He was the first in 1673 to discover and conduct scientific experiments with microorganisms, using simple single-lensed microscopes of his own design. Robert Hooke, a contemporary of Leeuwenhoek, also used microscopy to observe microbial life in the form of the fruiting bodies of moulds. In his 1665 book "Micrographia", he made drawings of studies, and he coined the term "cell".


title: Microorganism

text: Louis Pasteur (1822–1895) exposed boiled broths to the air, in vessels that contained a filter to prevent particles from passing through to the growth medium, and also in vessels without a filter, but with air allowed in via a curved tube so dust particles would settle and not come in contact with the broth. By boiling the broth beforehand, Pasteur ensured that no microorganisms survived within the broths at the beginning of his experiment. Nothing grew in the broths in the course of Pasteur's experiment. This meant that the living organisms that grew in such broths came from outside, as spores on dust, rather than spontaneously generated within the broth. Thus, Pasteur refuted the theory of spontaneous generation and supported the germ theory of disease.


title: Microorganism

text: In 1876, Robert Koch (1843–1910) established that microorganisms can cause disease. He found that the blood of cattle that were infected with anthrax always had large numbers of "Bacillus anthracis". Koch found that he could transmit anthrax from one animal to another by taking a small sample of blood from the infected animal and injecting it into a healthy one, and this caused the healthy animal to become sick. He also found that he could grow the bacteria in a nutrient broth, then inject it into a healthy animal, and cause illness. Based on these experiments, he devised criteria for establishing a causal link between a microorganism and a disease and these are now known as Koch's postulates. Although these postulates cannot be applied in all cases, they do retain historical importance to the development of scientific thought and are still being used today.


title: Microorganism

text: The discovery of microorganisms such as "Euglena" that did not fit into either the animal or plant kingdoms, since they were photosynthetic like plants, but motile like animals, led to the naming of a third kingdom in the 1860s. In 1860 John Hogg called this the Protoctista, and in 1866 Ernst Haeckel named it the Protista.


title: Microorganism

text: The work of Pasteur and Koch did not accurately reflect the true diversity of the microbial world because of their exclusive focus on microorganisms having direct medical relevance. It was not until the work of Martinus Beijerinck and Sergei Winogradsky late in the nineteenth century that the true breadth of microbiology was revealed. Beijerinck made two major contributions to microbiology: the discovery of viruses and the development of enrichment culture techniques. While his work on the tobacco mosaic virus established the basic principles of virology, it was his development of enrichment culturing that had the most immediate impact on microbiology by allowing for the cultivation of a wide range of microbes with wildly different physiologies. Winogradsky was the first to develop the concept of chemolithotrophy and to thereby reveal the essential role played by microorganisms in geochemical processes. He was responsible for the first isolation and description of both nitrifying and nitrogen-fixing bacteria. French-Canadian microbiologist Felix d'Herelle co-discovered bacteriophages and was one of the earliest applied microbiologists.


title: Microorganism

text: Microorganisms can be found almost anywhere on Earth. Bacteria and archaea are almost always microscopic, while a number of eukaryotes are also microscopic, including most protists, some fungi, as well as some micro-animals and plants. Viruses are generally regarded as not living and therefore not considered to be microorganisms, although a subfield of microbiology is virology, the study of viruses.


title: Microorganism

text: Single-celled microorganisms were the first forms of life to develop on Earth, approximately 3.5 billion years ago. Further evolution was slow, and for about 3 billion years in the Precambrian eon, (much of the history of life on Earth), all organisms were microorganisms. Bacteria, algae and fungi have been identified in amber that is 220 million years old, which shows that the morphology of microorganisms has changed little since at least the Triassic period. The newly discovered biological role played by nickel, however – especially that brought about by volcanic eruptions from the Siberian Traps – may have accelerated the evolution of methanogens towards the end of the Permian–Triassic extinction event.


title: Microorganism

text: Microorganisms tend to have a relatively fast rate of evolution. Most microorganisms can reproduce rapidly, and bacteria are also able to freely exchange genes through conjugation, transformation and transduction, even between widely divergent species. This horizontal gene transfer, coupled with a high mutation rate and other means of transformation, allows microorganisms to swiftly evolve (via natural selection) to survive in new environments and respond to environmental stresses. This rapid evolution is important in medicine, as it has led to the development of multidrug resistant pathogenic bacteria, "superbugs", that are resistant to antibiotics.


title: Microorganism

text: A possible transitional form of microorganism between a prokaryote and a eukaryote was discovered in 2012 by Japanese scientists. "Parakaryon myojinensis" is a unique microorganism larger than a typical prokaryote, but with nuclear material enclosed in a membrane as in a eukaryote, and the presence of endosymbionts. This is seen to be the first plausible evolutionary form of microorganism, showing a stage of development from the prokaryote to the eukaryote.


title: Microorganism

text: Archaea are prokaryotic unicellular organisms, and form the first domain of life in Carl Woese's three-domain system. A prokaryote is defined as having no cell nucleus or other membrane bound-organelle. Archaea share this defining feature with the bacteria with which they were once grouped. In 1990 the microbiologist Woese proposed the three-domain system that divided living things into bacteria, archaea and eukaryotes, and thereby split the prokaryote domain.


title: Microorganism

text: Archaea differ from bacteria in both their genetics and biochemistry. For example, while bacterial cell membranes are made from phosphoglycerides with ester bonds, archaean membranes are made of ether lipids. Archaea were originally described as extremophiles living in extreme environments, such as hot springs, but have since been found in all types of habitats. Only now are scientists beginning to realize how common archaea are in the environment, with Thermoproteota (formerly Crenarchaeota) being the most common form of life in the ocean, dominating ecosystems below 150 m in depth. These organisms are also common in soil and play a vital role in ammonia oxidation.


title: Microorganism

text: The combined domains of archaea and bacteria make up the most diverse and abundant group of organisms on Earth and inhabit practically all environments where the temperature is below +140 °C. They are found in water, soil, air, as the microbiome of an organism, hot springs and even deep beneath the Earth's crust in rocks. The number of prokaryotes is estimated to be around five nonillion, or 5 × 10, accounting for at least half the biomass on Earth.


title: Microorganism

text: The biodiversity of the prokaryotes is unknown, but may be very large. A May 2016 estimate, based on laws of scaling from known numbers of species against the size of organism, gives an estimate of perhaps 1 trillion species on the planet, of which most would be microorganisms. Currently, only one-thousandth of one percent of that total have been described. Archael cells of some species aggregate and transfer DNA from one cell to another through direct contact, particularly under stressful environmental conditions that cause DNA damage.


title: Microorganism

text: Bacteria like archaea are prokaryotic – unicellular, and having no cell nucleus or other membrane-bound organelle. Bacteria are microscopic, with a few extremely rare exceptions, such as "Thiomargarita namibiensis". Bacteria function and reproduce as individual cells, but they can often aggregate in multicellular colonies. Some species such as myxobacteria can aggregate into complex swarming structures, operating as multicellular groups as part of their life cycle, or form clusters in bacterial colonies such as "E.coli".


title: Microorganism

text: Their genome is usually a circular bacterial chromosome – a single loop of DNA, although they can also harbor small pieces of DNA called plasmids. These plasmids can be transferred between cells through bacterial conjugation. Bacteria have an enclosing cell wall, which provides strength and rigidity to their cells. They reproduce by binary fission or sometimes by budding, but do not undergo meiotic sexual reproduction. However, many bacterial species can transfer DNA between individual cells by a horizontal gene transfer process referred to as natural transformation. Some species form extraordinarily resilient spores, but for bacteria this is a mechanism for survival, not reproduction. Under optimal conditions bacteria can grow extremely rapidly and their numbers can double as quickly as every 20 minutes.


title: Microorganism

text: Most living things that are visible to the naked eye in their adult form are eukaryotes, including humans. However, many eukaryotes are also microorganisms. Unlike bacteria and archaea, eukaryotes contain organelles such as the cell nucleus, the Golgi apparatus and mitochondria in their cells. The nucleus is an organelle that houses the DNA that makes up a cell's genome. DNA (Deoxyribonucleic acid) itself is arranged in complex chromosomes.


title: Microorganism

text: Mitochondria are organelles vital in metabolism as they are the site of the citric acid cycle and oxidative phosphorylation. They evolved from symbiotic bacteria and retain a remnant genome. Like bacteria, plant cells have cell walls, and contain organelles such as chloroplasts in addition to the organelles in other eukaryotes. Chloroplasts produce energy from light by photosynthesis, and were also originally symbiotic bacteria.


title: Microorganism

text: Unicellular eukaryotes consist of a single cell throughout their life cycle. This qualification is significant since most multicellular eukaryotes consist of a single cell called a zygote only at the beginning of their life cycles. Microbial eukaryotes can be either haploid or diploid, and some organisms have multiple cell nuclei.


title: Microorganism

text: Unicellular eukaryotes usually reproduce asexually by mitosis under favorable conditions. However, under stressful conditions such as nutrient limitations and other conditions associated with DNA damage, they tend to reproduce sexually by meiosis and syngamy.


title: Microorganism

text: Of eukaryotic groups, the protists are most commonly unicellular and microscopic. This is a highly diverse group of organisms that are not easy to classify. Several algae species are multicellular protists, and slime molds have unique life cycles that involve switching between unicellular, colonial, and multicellular forms. The number of species of protists is unknown since only a small proportion has been identified. Protist diversity is high in oceans, deep sea-vents, river sediment and an acidic river, suggesting that many eukaryotic microbial communities may yet be discovered.


title: Microorganism

text: The fungi have several unicellular species, such as baker's yeast ("Saccharomyces cerevisiae") and fission yeast ("Schizosaccharomyces pombe"). Some fungi, such as the pathogenic yeast "Candida albicans", can undergo phenotypic switching and grow as single cells in some environments, and filamentous hyphae in others.


title: Microorganism

text: The green algae are a large group of photosynthetic eukaryotes that include many microscopic organisms. Although some green algae are classified as protists, others such as charophyta are classified with embryophyte plants, which are the most familiar group of land plants. Algae can grow as single cells, or in long chains of cells. The green algae include unicellular and colonial flagellates, usually but not always with two flagella per cell, as well as various colonial, coccoid, and filamentous forms. In the Charales, which are the algae most closely related to higher plants, cells differentiate into several distinct tissues within the organism. There are about 6000 species of green algae.


title: Microorganism

text: Microorganisms are found in almost every habitat present in nature, including hostile environments such as the North and South poles, deserts, geysers, and rocks. They also include all the marine microorganisms of the oceans and deep sea. Some types of microorganisms have adapted to extreme environments and sustained colonies; these organisms are known as extremophiles. Extremophiles have been isolated from rocks as much as 7 kilometres below the Earth's surface, and it has been suggested that the amount of organisms living below the Earth's surface is comparable with the amount of life on or above the surface. Extremophiles have been known to survive for a prolonged time in a vacuum, and can be highly resistant to radiation, which may even allow them to survive in space. Many types of microorganisms have intimate symbiotic relationships with other larger organisms; some of which are mutually beneficial (mutualism), while others can be damaging to the host organism (parasitism). If microorganisms can cause disease in a host they are known as pathogens and then they are sometimes referred to as "microbes".


title: Microorganism

text: Microorganisms play critical roles in Earth's biogeochemical cycles as they are responsible for decomposition and nitrogen fixation.


title: Microorganism

text: Bacteria use regulatory networks that allow them to adapt to almost every environmental niche on earth. A network of interactions among diverse types of molecules including DNA, RNA, proteins and metabolites, is utilised by the bacteria to achieve regulation of gene expression. In bacteria, the principal function of regulatory networks is to control the response to environmental changes, for example nutritional status and environmental stress. A complex organization of networks permits the microorganism to coordinate and integrate multiple environmental signals.


title: Microorganism

text: Extremophiles are microorganisms that have adapted so that they can survive and even thrive in extreme environments that are normally fatal to most life-forms. Thermophiles and hyperthermophiles thrive in high temperatures. Psychrophiles thrive in extremely low temperatures. – Temperatures as high as , as low as Halophiles such as "Halobacterium salinarum" (an archaean) thrive in high salt conditions, up to saturation. Alkaliphiles thrive in an alkaline pH of about 8.5–11. Acidophiles can thrive in a pH of 2.0 or less. Piezophiles thrive at very high pressures: up to 1,000–2,000 atm, down to 0 atm as in a vacuum of space. A few extremophiles such as "Deinococcus radiodurans" are radioresistant, resisting radiation exposure of up to 5k Gy. Extremophiles are significant in different ways. They extend terrestrial life into much of the Earth's hydrosphere, crust and atmosphere, their specific evolutionary adaptation mechanisms to their extreme environment can be exploited in biotechnology, and their very existence under such extreme conditions increases the potential for extraterrestrial life.


title: Microorganism

text: The nitrogen cycle in soils depends on the fixation of atmospheric nitrogen. This is achieved by a number of diazotrophs. One way this can occur is in the root nodules of legumes that contain symbiotic bacteria of the genera "Rhizobium", "Mesorhizobium", "Sinorhizobium", "Bradyrhizobium", and "Azorhizobium".


title: Microorganism

text: The roots of plants create a narrow region known as the rhizosphere that supports many microorganisms known as the root microbiome.


title: Microorganism

text: These microorganisms in the root microbiome are able to interact with each other and surrounding plants through signals and cues. For example, mycorrhizal fungi are able to communicate with the root systems of many plants through chemical signals between both the plant and fungi. This results in a mutualistic symbiosis between the two. However, these signals can be eavesdropped by other microorganisms, such as the soil bacteria, "Myxococcus xanthus", which preys on other bacteria. Eavesdropping, or the interception of signals from unintended receivers, such as plants and microorganisms, can lead to large-scale, evolutionary consequences. For example, signaler-receiver pairs, like plant-microorganism pairs, may lose the ability to communicate with neighboring populations because of variability in eavesdroppers. In adapting to avoid local eavesdroppers, signal divergence could occur and thus, lead to the isolation of plants and microorganisms from the inability to communicate with other populations.


title: Microorganism

text: A lichen is a symbiosis of a macroscopic fungus with photosynthetic microbial algae or cyanobacteria.


title: Microorganism

text: Microorganisms are useful in producing foods, treating waste water, creating biofuels and a wide range of chemicals and enzymes. They are invaluable in research as model organisms. They have been weaponised and sometimes used in warfare and bioterrorism. They are vital to agriculture through their roles in maintaining soil fertility and in decomposing organic matter.


title: Microorganism

text: Microorganisms are used in a fermentation process to make yoghurt, cheese, curd, kefir, ayran, xynogala, and other types of food. Fermentation cultures provide flavour and aroma, and inhibit undesirable organisms. They are used to leaven bread, and to convert sugars to alcohol in wine and beer. Microorganisms are used in brewing, wine making, baking, pickling and other food-making processes.


title: Microorganism

text: These depend for their ability to clean up water contaminated with organic material on microorganisms that can respire dissolved substances. Respiration may be aerobic, with a well-oxygenated filter bed such as a slow sand filter. Anaerobic digestion by methanogens generate useful methane gas as a by-product.


title: Microorganism

text: Microorganisms are used in fermentation to produce ethanol, and in biogas reactors to produce methane. Scientists are researching the use of algae to produce liquid fuels, and bacteria to convert various forms of agricultural and urban waste into usable fuels.


title: Microorganism

text: Microorganisms are used to produce many commercial and industrial chemicals, enzymes and other bioactive molecules. Organic acids produced on a large industrial scale by microbial fermentation include acetic acid produced by acetic acid bacteria such as "Acetobacter aceti", butyric acid made by the bacterium "Clostridium butyricum", lactic acid made by "Lactobacillus" and other lactic acid bacteria, and citric acid produced by the mould fungus "Aspergillus niger".


title: Microorganism

text: Microorganisms are used to prepare bioactive molecules such as Streptokinase from the bacterium "Streptococcus", Cyclosporin A from the ascomycete fungus "Tolypocladium inflatum", and statins produced by the yeast "Monascus purpureus".


title: Microorganism

text: Microorganisms are essential tools in biotechnology, biochemistry, genetics, and molecular biology. The yeasts "Saccharomyces cerevisiae" and "Schizosaccharomyces pombe" are important model organisms in science, since they are simple eukaryotes that can be grown rapidly in large numbers and are easily manipulated. They are particularly valuable in genetics, genomics and proteomics. Microorganisms can be harnessed for uses such as creating steroids and treating skin diseases. Scientists are also considering using microorganisms for living fuel cells, and as a solution for pollution.


title: Microorganism

text: In the Middle Ages, as an early example of biological warfare, diseased corpses were thrown into castles during sieges using catapults or other siege engines. Individuals near the corpses were exposed to the pathogen and were likely to spread that pathogen to others.


title: Microorganism

text: In modern times, bioterrorism has included the 1984 Rajneeshee bioterror attack and the 1993 release of anthrax by Aum Shinrikyo in Tokyo.


title: Microorganism

text: Microbes can make nutrients and minerals in the soil available to plants, produce hormones that spur growth, stimulate the plant immune system and trigger or dampen stress responses. In general a more diverse set of soil microbes results in fewer plant diseases and higher yield.


title: Microorganism

text: Microorganisms can form an endosymbiotic relationship with other, larger organisms. For example, microbial symbiosis plays a crucial role in the immune system. The microorganisms that make up the gut flora in the gastrointestinal tract contribute to gut immunity, synthesize vitamins such as folic acid and biotin, and ferment complex indigestible carbohydrates. Some microorganisms that are seen to be beneficial to health are termed probiotics and are available as dietary supplements, or food additives.


title: Microorganism

text: Microorganisms are the causative agents (pathogens) in many infectious diseases. The organisms involved include pathogenic bacteria, causing diseases such as plague, tuberculosis and anthrax; protozoan parasites, causing diseases such as malaria, sleeping sickness, dysentery and toxoplasmosis; and also fungi causing diseases such as ringworm, candidiasis or histoplasmosis. However, other diseases such as influenza, yellow fever or AIDS are caused by pathogenic viruses, which are not usually classified as living organisms and are not, therefore, microorganisms by the strict definition. No clear examples of archaean pathogens are known, although a relationship has been proposed between the presence of some archaean methanogens and human periodontal disease. Numerous microbial pathogens are capable of sexual processes that appear to facilitate their survival in their infected host.


title: Microorganism

text: Hygiene is a set of practices to avoid infection or food spoilage by eliminating microorganisms from the surroundings. As microorganisms, in particular bacteria, are found virtually everywhere, harmful microorganisms may be reduced to acceptable levels rather than actually eliminated. In food preparation, microorganisms are reduced by preservation methods such as cooking, cleanliness of utensils, short storage periods, or by low temperatures. If complete sterility is needed, as with surgical equipment, an autoclave is used to kill microorganisms with heat and pressure.


title: BlueStacks

text: BlueStacks is an American technology company known for the BlueStacks App Player and other cloud-based cross-platform products. The BlueStacks App Player allows Android applications to run on computers running Microsoft Windows or macOS. The company was founded in 2009 by Jay Vaishnav, Suman Saraf, and Rosen Sharma.


title: BlueStacks

text: The company was announced in May 2011 at the Citrix Synergy conference in San Francisco. Citrix CEO Mark Templeton demonstrated an early version of BlueStacks onstage and announced that the companies had formed a partnership. The public alpha version of App Player was launched in October 2011. App Player exited beta on June 7, 2014. In July 2014, Samsung announced it had invested in BlueStacks. This brought total outside investment in BlueStacks to $26 million.


title: BlueStacks

text: The App Player, software that virtualizes an Android OS, can be downloaded for Windows and macOS. The software's basic features are free to download and use. Advanced optional features require a paid monthly subscription. The company claims the App Player can run 1.5 million Android apps as of November 2019. As of February 2021, BlueStacks claimed its apps were downloaded over 1 billion times. App Player features mouse, keyboard, and external touch-pad controls.


title: BlueStacks

text: In June 2012, the company released an alpha version of its App Player software for macOS, while the beta version was released in December of that year.


title: BlueStacks

text: In April 2015, BlueStacks, Inc. announced that a new version of App Player for macOS, 2.0, was in development, which was released in July. In December 2015, BlueStacks, Inc. released the new version BlueStacks 2.0 which lets users run multiple Android applications simultaneously. BlueStacks 2.0 was also available for Mac OS X 10.9 Mavericks or later, till 2018.


title: BlueStacks

text: In April 2016, the company released BlueStacks TV which integrated Twitch.tv directly into the BlueStacks App Player. This addition allows users to livestream their apps to Twitch without the need for extra hardware or software.


title: BlueStacks

text: BlueStacks released Facebook Live integration in September 2016, allowing users to stream their gameplay to their Facebook profiles, Pages they control, or Facebook Groups they belong to.


title: BlueStacks

text: In July 2017, BlueStacks released BlueStacks 3 based on a brand new engine and front-end design. BlueStacks 3 added App Center which personalizes game suggestions, an account system, chat, new keymapping interface, and multi-instance. Multi-instance allows users to launch multiple BlueStacks windows using either the same or different Google Play account.


title: BlueStacks

text: In January 2018, BlueStacks announced the release of the BlueStacks + N Beta which runs on Android 7 (Android Nougat) and claimed to be the first and only Android gaming platform to have Android 7 at the time, since the majority of Android emulators ran Android 4.4 (KitKat), including prior BlueStacks versions. This beta version was powered by an upgraded "HyperG" graphics engine allowing BlueStacks to utilize the full array of Android 7 APIs.


title: BlueStacks

text: In September 2018, BlueStacks announced the release of its latest flagship version, BlueStacks 4. BlueStacks 4 benchmarks 6-8 times faster than every major mobile phone according to the Antutu benchmark. BlueStacks 4 also includes dynamic resource management which only initializes the required Android libraries, thus freeing resources. BlueStacks 4 provides a new dock and search user interface. A new AI powered key-mapping tool auto maps keys in supported games with key customization also available for further tweaking. In addition, BlueStacks 4 supports both 32-bit and 64-bit version of Android 7.1.2 Nougat.


title: BlueStacks

text: In January 2019, BlueStacks released a 64-bit version of BlueStacks 4 via its early access program. This version runs on a 64-bit version of Android 7.1.2 which allows for improved performance, and more efficient memory usage. The prerequisites for running this build include running a 64-bit version of Windows 8 or later, with virtualization enabled, and Hyper-V disabled. This 64-bit release allows the installation and usage of ARM64-v8a Android applications.


title: BlueStacks

text: In May 2021, BlueStacks released BlueStacks 5, still based on Android 7.1.2 but also Android 9 (Android Pie), if chosen by user.


title: BlueStacks

text: In September 2021, BlueStacks launched BlueStacks X, a cloud-based Android gaming platform. Driven by Hybrid Cloud technology, BlueStacks X is powered by now.gg, a sister company to BlueStacks.


title: BlueStacks

text: Current minimum requirements for BlueStacks App Player 5 for Windows are: Windows 7 or higher, 4 GB of RAM, 5 GB of disk space, and an Intel or AMD processor. BlueStacks clashes with the BitDefender antivirus software. Current minimum requirements for BlueStacks for macOS are: 64-bit macOS Sierra or higher, 4 GB RAM, 8 GB disk space, Intel HD 5200 or higher graphics processor, and an Intel or AMD processor. BlueStacks does not yet not support computers with Apple M1 chips, macOS Monterey, or macOS Ventura.


title: Airbus A330neo

text: The Airbus A330neo ("neo" for "New Engine Option") is a wide-body airliner developed by Airbus from the Airbus A330 (now A330"ceo" – "Current Engine Option"). A new version with modern engines comparable with those developed for the Boeing 787 was called for by operators of the original A330 series. It was launched on 14 July 2014 at the Farnborough Airshow, promising 14% better fuel economy per seat. It is exclusively powered by the Rolls-Royce Trent 7000 which has double the bypass ratio of its predecessor.


title: Airbus A330neo

text: Its two versions are based on the A330-200 and -300: the -800 has a range of with 257 passengers while the -900 covers with 287 passengers. The -900 made its maiden flight on 19 October 2017 and received its EASA type certificate on 26 September 2018; it was first delivered to TAP Air Portugal on 26 November 2018 and entered service on 15 December. The -800 made its first flight on 6 November 2018 and received EASA type certification on 13 February 2020; the first two -800s were delivered to Kuwait Airways on 29 October 2020 and entered service on 20 November.


title: Airbus A330neo

text: , a total of 293 A330neo family aircraft had been ordered by more than 24 customers, of which 77 aircraft had been delivered.


title: Airbus A330neo

text: At the Boeing 787 launch in 2004, Airbus' initial response was an improved A330. After negative feedback from airlines and lessors, the A350 XWB became a new design in 2006. After the A320neo launch in December 2010 and its commercial success, the largest airline of Malaysia – an all-Airbus operator – AirAsia asked Airbus to re-engine the A330. New engines like the GEnx or Rolls-Royce Trent 1000 developed for the 787 could offer a 12%–15% fuel burn improvement, and sharklets at least 2%.


title: Airbus A330neo

text: Airbus sales chief John Leahy's argument was that the lower purchase price of an A330 even without new engines make the economics of buying an A330 competitive at midrange routes with that of the Boeing 787. An A330neo would accelerate the demise of the similarly sized A350-800. Airbus also considered re-engining the A380 but was wary of having two major modification programs simultaneously.


title: Airbus A330neo

text: In March 2014, Delta Air Lines expressed an interest in the A330neo to replace its ageing, 20+-year-old Boeing 767-300ER jets. In the 250-300-seat market, CIT Group believed an A330neo enables profitability on shorter ranges where the longer-range A350 and Boeing 787 are not optimised. CIT said that the A350-800 was not as efficient as it would like, and Air Lease Corp. added that the company did not consider it reasonable to take the A350-800 and A330neo as they saw no sustainable coexistence of the two aircraft.


title: Airbus A330neo

text: AirAsia X ended flights to London and Paris from Kuala Lumpur in 2012 because their Airbus A340s were not fuel-efficient enough and would try again with A330s. As Airbus gradually increased output of the new A350, prolonging the production run of the A330 could help to maintain profitability. After Emirates cancelled 70 orders for the A350, Airbus said it continued to work on re-engining the smaller A330.


title: Airbus A330neo

text: On 14 July 2014 at the Farnborough Airshow, Airbus launched the A330neo programme, to be powered by the new Rolls-Royce Trent 7000. It would improve the fuel burn per seat by 14%. Airbus hoped to sell 1,000 A330neo aircraft. Its range would increase by and although 95% of the parts would be common with the A330ceo, maintenance costs would be lower. New winglets, 3.7 metres wider and similar to those of the A350 XWB, still within ICAO category E airport requirements, along with new engine pylons, would improve aerodynamics by 4%.


title: Airbus A330neo

text: The A330neo's development costs were expected to have an impact of around −0.7% on Airbus's return on sales target from 2015 to 2017, an estimated $2 billion (£1.18 billion). Airbus stated that lower capital cost would make the A330neo the most cost-efficient medium-range wide-body airliner. Airbus said that it could pursue demand for 4,000 aircraft and that there was an open market for 2,600 jets not already addressed by backlogs with operators already using A330s. Aerodynamic modifications would include a re-twisted wing and optimised slats.


title: Airbus A330neo

text: In 2014, "The Airline Monitor"'s Ed Greenslet stated that the A330neo would have the advantage of not being designed to fly 8,000 nmi, unlike the A350 and Boeing 787 which were thus less economical on shorter routes, although "the vast majority of long-haul markets is 4,000 nmi or less".


title: Airbus A330neo

text: He also believed that an "A330neo would enjoy a monopoly in its segment instantly", with the Boeing 767 "essentially out of production", the Boeing 757 not replaced while the A321neo and the 737-9 are smaller and had less range, and that launching the A330neo would probably kill the smallest A350-800.


title: Airbus A330neo

text: John Leahy estimated that the A330-900 would have operating costs on par with the 787-9, but would be available at 25% lower capital costs and could reach a production rate of 10 per month after a 7/8 per month rate at the production start. Both A330neo variants were expected to have a maximum take-off weight of 242 t. The type design was frozen in late 2015.


title: Airbus A330neo

text: Boeing Vice Chairman and Commercial Airplanes CEO Ray Conner dismissed the A330neo as a 2004 revamp which cannot match the 787's direct operating costs, being heavier and having a wing only slightly improved from the 1980s design, and claimed the 787-10 was almost 30% more efficient per-seat than the previous A330-300 and that a new engine would not close the gap – but he acknowledged that it could be a threat as it put pressure on Boeing as it sought to break even after 850–1,000 787 deliveries.


title: Airbus A330neo

text: On 7 September 2015, Airbus announced that it had begun production of the first A330neo with the construction of its centre wingbox and engine pylon. Final assembly of the first aircraft, an A330-900, started in September 2016 at the Airbus Toulouse site with the joining of the wings to the centre fuselage at the station 40. In December 2016, the programme schedule slipped by six weeks due to marginal engine development at Rolls-Royce, and launch customer TAP Air Portugal projected its first A330neo would be delivered in March 2018.


title: Airbus A330neo

text: The first aircraft left the paint shop in December 2016, awaiting its engines. By April 2017, the Trent 7000s were to be installed later during the summer, so that the first flight was delayed until September.


title: Airbus A330neo

text: Due to the delay, TAP Air Portugal was not expected to receive the first A330neo until the end of the first half of 2018, or even in the third quarter.


title: Airbus A330neo

text: The engines were shipped to Airbus in June. The aircraft complete with engines showed at Toulouse in September before its first flight.


title: Airbus A330neo

text: Major structures of the first A330-800 were entering production in October 2017: high-lift devices are installed on the wing in Bremen, fuselage sections are built in Hamburg, the centre wing-box in Nantes, titanium engine pylons in Toulouse and sharklet wingtips in Korea. Its final assembly started in November 2017, on track for its planned first flight in mid-2018.


title: Airbus A330neo

text: Structural assembly was completed by February 2018, having its flight-test instruments installed and waiting for its engines before its 300h flight-test programme.


title: Airbus A330neo

text: At this time, production aircraft progressed through the final assembly line with the first 'Airspace' cabin interior being fitted.


title: Airbus A330neo

text: In April 2020, the production rate decreased from 3.5 to 2 per month due to the impact of the COVID-19 pandemic on aviation, and finished planes were stored while waiting for deferred deliveries.


title: Airbus A330neo

text: The A330-900 first flight on 19 October 2017 was a debut of the 1,400 hours flight test campaign involving three prototypes plus the first production aircraft: 1,100 flight hours for the A330-900 and 300 flight hours for the A330-800, targeting mid-2018 EASA and FAA Type Certification. The 4h 15m flight reached and . It should establish certain maximum operating points and achieve an initial handling qualities assessment including at high angle of attack. This first aircraft, MSN1795, was scheduled to perform 600 h and was to be joined the following month by the second, MSN1813, which will fly 500 h, before the third, MSN1819, the first customer aircraft for TAP Portugal with a complete cabin.


title: Airbus A330neo

text: Two flight test engineers and two engine specialists monitored the 60GB per hour output of 1,375 sensors and 98,000 parameters, including strips of microelectromechanical systems to measure aerodynamic pressure distribution across the wing. MSN1795 was to undertake simulated icing tests and cold-weather tests in Canada, noise assessment, autoland testing and high angle-of-attack, minimum-unstick checks during rotation with a tail bumper. MSN1813 was to test natural icing conditions, assess hot and high conditions in the United Arab Emirates and La Paz, and fly 150h of route-proving; it has rakes and pressure sensors in the engine flows to compare actual thrust with ground bench measurements. MSN1819 was to validate the Airspace cabin interior fitting with artificial passengers for ventilation analysis and cabin environment measurements.


title: Airbus A330neo

text: The second test aircraft made its maiden flight on 4 December, to be used to validate aerodynamic & engine performance and airline operations.


title: Airbus A330neo

text: By the end of January 2018, the first logged almost 200h in 58 flights while the second had accumulated nearly 120h in 30 flights.


title: Airbus A330neo

text: Its flight envelope was fully opened including flutter and stall tests to complete powerplant calibration and strake configuration has been frozen.


title: Airbus A330neo

text: Airbus commenced autopilot, autoland and high-speed performance testing, and was to move on to hot- and cold-weather tests, as well as noise and icing tests, over the following three months.


title: Airbus A330neo

text: As of 10 April 2018, the two test aircraft had logged over 200 flights and more than 700 hours, testing −27 °C cold weather, natural icing, crosswind landing, 37 °C and hot and high operations.


title: Airbus A330neo

text: The first TAP Air Portugal aircraft made its first flight on 15 May 2018; it joined the two previous test aircraft to check the cabin systems: air conditioning, crew rest, etc.


title: Airbus A330neo

text: It started the final certification step on 18 June: function and reliability tests or route proving, including ETOPS, diversion airport landing, and testing ground handling over 150 flight test hours, as the flight test programme reached 1,000 hours.


title: Airbus A330neo

text: Entry into service was planned for the third quarter of 2018 and ETOPS was to be approved in October for 330min.


title: Airbus A330neo

text: EASA granted the A330-941 type certificate on 26 September 2018, with ETOPS not yet approved. ETOPS 180 min was approved on 14 November, restricted to engines with fewer than 500 flight cycles.


title: Airbus A330neo

text: Airbus expects the FAA type certification with 180 min ETOPS by the end of 2018 and 330 min ETOPS in the first half of 2019.


title: Airbus A330neo

text: The maiden flight of the -800 took place on 6 November 2018; the 4h 4min flight inaugurated a 350h test program aiming for mid-2019 type certification, for delivery in the first half of 2020 to launch operator Kuwait Airways.


title: Airbus A330neo

text: By late March 2019, it was halfway through the 300 hours flight-test programme, having completed 44 flights in 149 hours. The -800 received EASA type certification with 180-minute ETOPS on 13 February 2020; ETOPS clearance beyond 180 minutes was awarded on 2 April.


title: Airbus A330neo

text: Leased from Avolon, the first A330-900 was delivered to TAP Air Portugal on 26 November 2018, featuring 298 seats: 34 full-flat business, 96 economy plus and 168 economy seats, and to be deployed from Portugal to the Americas and Africa.


title: Airbus A330neo

text: TAP made its first commercial flight on 15 December from Lisbon to São Paulo. The airline should receive 15 more A330neos in 2019 and fly the A330-900 from Lisbon to Chicago O'Hare and Washington Dulles from June 2019, both five times a week.


title: Airbus A330neo

text: On the occasion of the 19 October 2017 first flight, an increase to MTOW by mid-2020 was announced, with a few changes to the landing gear and brakes, increasing its range by compared to the current A330neo or A330ceo.


title: Airbus A330neo

text: Airbus was expecting a short 30–40h test campaign, as multiple tests were conducted with the previous variant adapted to higher weight, including flight performance and noise assessment.


title: Airbus A330neo

text: The heavier structure allows a transpacific range, and is balanced by a weight-reduction effort, keeping the same empty weight and payload.


title: Airbus A330neo

text: On 8 October 2020, the 251 t A330-900 was EASA-certified, before introduction by Corsair International.


title: Airbus A330neo

text: Retaining 99% spares commonality, it offers more payload while strengthening the landing-gear and extending the time before overhaul interval from 10 to 12 years.


title: Airbus A330neo

text: On 31 March 2021, Corsair took delivery of the first 251t Airbus A330-900 in a three-class, 352-seat configuration.


title: Airbus A330neo

text: The larger 112-inch Trent 7000 is 11% more efficient than the 97.5-inch Trent 700 engine, with a 2% loss due to increased weight and 1% due to additional drag from the larger engine, but the sharklets and aero optimization regains 4% for a 12% fuel advantage per trip. Furthermore, fuel consumption per seat is improved by 2% due to the rearranged cabin (Space-Flex and Smart-Lav) with increased seating, offering a 14% fuel burn reduction per seat for the new −900 compared to the previous 235-tonne −300 version. The newer 242-tonne −300 is already 2% more efficient.


title: Airbus A330neo

text: Airbus unveiled a distinctive cockpit windscreen to be featured on the A330neo, similar to that on the A350, and promised a new interior concept offering a better passenger experience on the A330neo. Initially based on the largest 242t MTOW A330, Airbus is studying an improvement to MTOW for the A330neo, which would match the figure originally given for the Airbus A350-800 before it was sidelined in favor of the A330neo. This would give the -900 a range to better compete with the 787-9’s


title: Airbus A330neo

text: Since the fan is enlarged from , the nacelles are mounted higher, necessitating extensive CFD analysis to avoid supersonic shock wave interference drag, as is the first slat's dog-tooth. The wing twist and belly fairings are tweaked to approach the lowest drag elliptical span-wise pressure distribution changed by the larger sharklets, like the flap track fairings shape to lower form drag.


title: Airbus A330neo

text: On the -800 at FL400, cruise fuel flow at Mach 0.82 and low weight is per hour at a higher weight and Mach 0.83.


title: Airbus A330neo

text: Candidate engines included variants of Rolls-Royce's Trent 1000 and General Electric's GEnx-1B. Both engine makers were reportedly interested in winning an exclusive deal should a re-engined A330 be offered. The Trent 1000 TEN (Thrust, Efficiency, New Technology) engine is under development for the 787-10, but Rolls-Royce intends to offer a broad power range.


title: Airbus A330neo

text: The A330neo uses the Rolls-Royce Trent 7000 engine, which is an electronic controlled bleed air variant of the Trent 1000 used on the Boeing 787-10. It will have a diameter fan and a 10:1 bypass ratio. They deliver a thrust of .


title: Airbus A330neo

text: The Trent is the exclusive powerplant, as Rolls-Royce offered better terms to obtain exclusivity. Customers bemoan the loss of competition among engine makers: Steven Udvar-Hazy, CEO of Air Lease Corporation, said that he wants a choice of engines, but Airbus has pointed out that equipping a commercial aircraft to handle more than one type of engine adds several hundred million dollars to the development cost. The head of Pratt and Whitney said: "Engines are no longer commodities...the optimization of the engine and the aircraft becomes more relevant."


title: Airbus A330neo

text: The decision to offer the aircraft with only one engine option is not unique to Airbus; the Boeing 777X will come equipped exclusively with General Electric GE9X engines, after Rolls Royce made a bid with its Advance configuration but was not selected.


title: Airbus A330neo

text: The A330-900 retains the fuselage length of the A330-300 and the similarly sized four-engined A340-300. Cabin optimisation allows ten additional seats on the A330-900 (310 passengers) with 18-inch-wide economy seats. The -900 should travel 6550 nmi (12,130 km) with 287 passengers (440 max).


title: Airbus A330neo

text: Delta expects a 20 percent reduction in operating cost per seat over the Boeing 767-300ER aircraft it replaces.


title: Airbus A330neo

text: Further reconfiguration of cabin facilities enables the –900 to seat up to 460 passengers in an all-economy layout. This exceeds the existing 440-seat maximum exit limit allowed by the type certificate, and requires a modification of the Type-A exit doors to meet emergency exit requirements.


title: Airbus A330neo

text: In November 2019, maximum accommodation increased to 460 seats, through the installation of new 'Type-A+' exits, with a dual-lane evacuation slide.


title: Airbus A330neo

text: The A330-800 retains the fuselage length of the A330-200, but can seat six more passengers (for a total of 252) with an optimised cabin featuring 18-inch-wide economy seats. The -800 should have a range of 7500 nmi (13,900 km) with 257 passengers (406 max).


title: Airbus A330neo

text: After the first flight of the -900 on 19 October 2017, Hawaiian Airlines (then the only customer for the -800) considered changing its order for six -800s,


title: Airbus A330neo

text: seeking to best fit its current network to Asia and North America whilst allowing for future growth, possibly to Europe.


title: Airbus A330neo

text: Demand for the -800 fell to 3%, whereas the -200 commanded 40% of the ceo deliveries: its range advantage has eroded with the increased capabilities of the -900, and although it offers lower fuel per trip, fuel per seat is higher.


title: Airbus A330neo

text: Demand for the -800 is limited by low fuel prices and the fact that the -200s it might replace after 2020 are still young (nine years on average). The Boeing 767-300/400s that the -800 might replace are 15 years older, and while Boeing considered relaunching production of the 767-300ER, mainly as an interim for American and United airlines, this was complicated by a 30-year-old design including obsolete cabin amenities.


title: Airbus A330neo

text: Before the introduction of the Boeing NMA, expected no earlier than 2027, the 95 A330 operators offer opportunities, and long-haul low-cost carriers could be interested in high density nine-abreast layouts for 386 seats over at the MTOW, more than a similarly loaded 787-8 and with up to 30 more seats.


title: Airbus A330neo

text: Production of the -800 beyond the prototype was in doubt, as Hawaiian was choosing between the Airbus A350-900 and the Boeing 787-8/9.


title: Airbus A330neo

text: In February 2018, Hawaiian was thought to be cancelling its order for six A330-800s, replacing them with Boeing 787-9s priced at less than $100–115m, close to their production cost of $80–90m, while Boeing Capital released Hawaiian from three 767-300ER leases well in advance.


title: Airbus A330neo

text: Hawaiian denied that the order for the A330-800 had been cancelled, but did not dismiss a new deal with Boeing.


title: Airbus A330neo

text: In March 2018, Hawaiian confirmed the cancellation of its order for six A330-800s and ordered ten B787-9s instead.


title: Airbus A330neo

text: In July 2018 a new memorandum of understanding from Uganda Airlines for two -800s revived interest in the shorter variant. A firm order from Kuwait Airways for eight A330-800s followed in October 2018, making it the largest customer of the type; it was subsequently confirmed that Kuwait Airways would be the launch customer for the -800, with certification expected in mid-2019 and first deliveries in the first half of 2020.


title: Airbus A330neo

text: Compared to the competing 787-8 with similar engines, the A330-800 has a 1% fuel-per-trip disadvantage (−5% for being heavier but +4% for the longer wingspan) but consumes 4% less fuel per seat with 13 more seats in an eight-abreast configuration, and 8% less with 27 more seats at nine-abreast with wide seats and aisles: the -800 is longer by 4 rows or 2.5 m (130 in).


title: Airbus A330neo

text: Airbus could limit its MTOW to and derate its engines to to optimise for the shorter routes to be targeted by the Boeing NMA, with the A321XLR tackling the lower end of the same niche.


title: Airbus A330neo

text: The first aircraft, configured with 226 seats including 23 in business class, was to be delivered to Kuwait Airways in March, but the airline postponed delivery until the third quarter of 2020 amid the COVID-19 pandemic. On 29 October, the first two A330-800s were delivered to Kuwait Airways; the airline has six more -800s on order. The A330-800 then operated its first revenue flight on 20 November, flying the short distance between Kuwait and Dubai. Uganda Airlines received their first A330-800 on 21 December, with the second unit expected in January 2021.


title: Airbus A330neo

text: Amazon Air and UPS Airlines pushed for a freighter version, stretching the A330-900 to carry more cargo over a shorter range, but retired 767s and A330s provide a lot of conversion potential.


title: Airbus A330neo

text: Development cost would be lower than for a new program as much of the engineering has already been done for the A330-200F, and more volume would be more appealing to express carriers.


title: Airbus A330neo

text: Third party analysis for a 3,350 nmi transatlantic flight shows that the 787-9 has a slight advantage over the A330-900 in cash cost per available seat miles, while the Airbus outperforms the Boeing once capital costs are included, based on the A330-900 cost an estimated $10.6m less.


title: Airbus A330neo

text: An A330-900 is worth $115 million in 2018, while a new B787-9 valuation is $145 million, up from $135 million in 2014, but it may have been sold for $110–15 million to prevent A330neo sales.


title: Airbus A330neo

text: Between the 2004 launch of the Dreamliner and the A330neo launch in 2014, the market was split almost equally between both, with between 900 and 920 A330ceos sold against 950 to 1,000 787-8/9s.


title: Airbus A330neo

text: Between 2014 and the neo first flight in October 2017, the A330/A330neo had 440 orders (excluding freighters) compared to 272 for the 787-8/9 (excluding the -10), or since the 787 launch, 1211 A330ceo/neos compared to 1106 787-8/9s.


title: Airbus A330neo

text: Teal Group's Richard Aboulafia believes that the A330neo should dominate the lower range and lower capacity end of the twin aisle market because the 787-8 has the high operating economics and unit price associated with its 8,000-nm range.


title: Airbus A330neo

text: Flightglobal Ascend Consultancy forecast 600 deliveries including 10% of -800 variants, less optimistic than Airbus' 1,000.


title: Airbus A330neo

text: At entry into service in 2018, sales were disappointing and A330 production was to be cut to 50 in 2019 down from 67 in 2017: while it was the widebody with the largest operator base with 1,390 deliveries since 1993, the fleet was still very young with only 46 aircraft retired. Airbus believed A330 operators would start fleet renewal beginning in 2020. With the exception of Delta, industry-leading airlines preferred the Boeing 787.


title: Airbus A330neo

text: Between January 2014 and November 2019, the A330/A330neo had 477 net orders (net of cancellations) compared to a total of 407 for all three variants of the 787. The A330neo program was the best-selling Airbus widebody over the same period.


title: Airbus A330neo

text: Airbus believes there is potential for the A330neo in the growing long-haul, low-cost carrier sector. While Airbus expected a market for over 1,000 A330neos, one pessimistic forecast reported in 2018 came in as low as 400 sales, in that the A330neo was late to the market and fuel prices had declined markedly over the years, reducing demand. 19% of A330 operators are already 787 customers though some A330 operators have been dual sourcing from both Boeing and Airbus. Leeham News, on the one hand considered the A330-800 does not really cover the upper end of New Midsize Airplane studied by Boeing for some years, on the other hand stated that the A330-800 provides Airbus a cost-effective entry to the upper end of the middle of the market. In May 2019, Airbus's chief commercial officer made clear the company has a “rock”, the A321neo, and a “hard place”, the A330-800, for any airframer intending to bring a new airplane into the middle of the market at a time when Boeing was mired in the 737 MAX crisis.


title: Airbus A330neo

text: Compared to a 283-seat, 9-abreast 787-9, Airbus claims a 1% lower fuel burn for the -900: 3% higher due to the higher OEW, but 4% lower due to the wider wingspan, and 3% lower fuel burn per seat in a 287-seat, 8-abreast configuration, reaching 7% with a 303-seat, 9-abreast layout.


title: Airbus A330neo

text: The five largest operators of A330neo are TAP Air Portugal (19), Delta Air Lines (19), Lion Air (8), Azul Brazilian Airlines (5) and Corsair International (5).


The Academy of Motion Picture Arts and Sciences (AMPAS, often pronounced ; also known as simply the Academy or the Motion Picture Academy) is a professional honorary organization with the stated goal of advancing the arts and sciences of motion pictures. The Academy's corporate management and general policies are overseen by a board of governors, which includes representatives from each of the craft branches.


title: Academy of Motion Picture Arts and Sciences

text: As of April 2020, the organization was estimated to consist of around 9,921 motion picture professionals. The Academy is an international organization and membership is open to qualified filmmakers around the world.


text: The Academy is known around the world for its annual Academy Awards, now officially and popularly known as "The Oscars".


text: In addition, the Academy holds the Governors Awards annually for lifetime achievement in film; presents Scientific and Technical Awards annually; gives Student Academy Awards annually to filmmakers at the undergraduate and graduate level; awards up to five Nicholl Fellowships in Screenwriting annually; and operates the Margaret Herrick Library (at the Fairbanks Center for Motion Picture Study) in Beverly Hills, California, and the Pickford Center for Motion Picture Study in Hollywood, Los Angeles. The Academy opened the Academy Museum of Motion Pictures in Los Angeles in 2021.


text: The notion of the Academy of Motion Picture Arts and Sciences (AMPAS) began with Louis B. Mayer, head of Metro-Goldwyn-Mayer (MGM). He said he wanted to create an organization that would mediate labor disputes without unions and improve the film industry's image. He met with actor Conrad Nagel, director Fred Niblo, and the head of the Association of Motion Picture Producers, Fred Beetson to discuss these matters. The idea of this elite club having an annual banquet was discussed, but no mention of awards at that time. They also established that membership into the organization would only be open to people involved in one of the five branches of the industry: actors, directors, writers, technicians, and producers.


text: After their brief meeting, Mayer gathered up a group of thirty-six people involved in the film industry and invited them to a formal banquet at the Ambassador Hotel in Los Angeles on January 11, 1927. That evening Mayer presented to those guests what he called the International Academy of Motion Picture Arts and Sciences. Everyone in the room that evening became a founder of the Academy. Between that evening and when the official Articles of Incorporation for the organization were filed on May 4, 1927, the "International" was dropped from the name, becoming the "Academy of Motion Picture Arts and Sciences".


text: Several organizational meetings were held prior to the first official meeting held on May 6, 1927. Their first organizational meeting was held on May 11 at the Millennium Biltmore Hotel. At that meeting Douglas Fairbanks, Sr. was elected as the first president of the Academy, while Fred Niblo was the first vice-president, and their first roster, composed of 230 members, was printed. That night, the Academy also bestowed its first honorary membership, to Thomas Edison. Initially, the Academy was broken down into five main groups, or branches, although this number of branches has grown over the years. The original five were: Producers, Actors, Directors, Writers and Technicians.


text: The initial concerns of the group had to do with labor." However, as time went on, the organization moved "further away from involvement in labor-management arbitrations and negotiations." One of several committees formed in those initial days was for "Awards of Merit," but it was not until May 1928 that the committee began to have serious discussions about the structure of the awards and the presentation ceremony. By July 1928, the board of directors had approved a list of 12 awards to be presented. During July the voting system for the Awards was established, and the nomination and selection process began. This "award of merit for distinctive achievement" is what we know now as the Academy Awards.


text: The initial location of the organization was 6912 Hollywood Boulevard. In November 1927, the Academy moved to the Roosevelt Hotel at 7010 Hollywood Boulevard, which was also the month the Academy's library began compiling a complete collection of books and periodicals dealing with the industry from around the world. In May 1928, the Academy authorized the construction of a state of the art screening room, to be located in the Club lounge of the hotel. The screening room was not completed until April 1929.


text: With the publication of Academy Reports (No. 1): "Incandescent Illumination" in July 1928, the Academy began a long history of publishing books to assist its members. Research Council of the Academy of Motion Picture Arts and Sciences trained Signal Corps officers, during World War II, who later won two Oscars, for "Seeds of Destiny" and "Toward Independence".


text: In 1929, Academy members, in a joint venture with the University of Southern California, created America's first film school to further the art and science of moving pictures. The school's founding faculty included Fairbanks (President of the Academy), D. W. Griffith, William C. deMille, Ernst Lubitsch, Irving Thalberg, and Darryl F. Zanuck.


text: 1930 saw another move, to 7046 Hollywood Boulevard, in order to accommodate the enlarging staff, and by December of that year the library was acknowledged as "having one of the most complete collections of information on the motion picture industry anywhere in existence." They remained at that location until 1935 when further growth caused them to move once again. This time, the administrative offices moved to one location, to the Taft Building at the corner of Hollywood and Vine, while the library moved to 1455 North Gordon Street.


text: In 1934, the Academy began publication of the "Screen Achievement Records Bulletin", which today is known as the "Motion Picture Credits Database". This is a list of film credits up for an Academy Award, as well as other films released in Los Angeles County, using research materials from the Academy's Margaret Herrick Library. Another publication of the 1930s was the first annual "Academy Players Directory" in 1937. The Directory was published by the Academy until 2006 when it was sold to a private concern. The Academy had been involved in the technical aspects of film making since its founding in 1927, and by 1938, the Science and Technology Council consisted of 36 technical committees addressing technical issues related to sound recording and reproduction, projection, lighting, film preservation, and cinematography.


text: In 2009, the inaugural Governors Awards were held, at which the Academy awards the Academy Honorary Award, the Jean Hersholt Humanitarian Award and the Irving G. Thalberg Memorial Award.


text: In 2016, the Academy became the target of criticism for its failure to recognize the achievements of minority professionals. For the second year in a row, all 20 nominees in the major acting categories were white. The president of the Academy Cheryl Boone Isaacs, the first African American and third woman to lead the Academy, denied in 2015 that there was a problem. When asked if the Academy had difficulty with recognizing diversity, she replied "Not at all. Not at all." When the nominations for acting were all white for a second year in a row Gil Robertson IV, president of the African American Film Critics Association called it "offensive." The actors' branch is "overwhelmingly white" and the question is raised whether conscious or unconscious racial biases played a role.


text: Spike Lee, interviewed shortly after the all-white nominee list was published, pointed to Hollywood leadership as the root problem, "We may win an Oscar now and then, but an Oscar is not going to fundamentally change how Hollywood does business. I'm not talking about Hollywood stars. I'm talking about executives. We're not in the room." Boone Isaacs also released a statement, in which she said "I am both heartbroken and frustrated about the lack of inclusion. This is a difficult but important conversation, and it's time for big changes." After Boone Isaac's statement, prominent African-Americans such as director Spike Lee, actors Will Smith and Jada Pinkett Smith, and activist Rev. Al Sharpton called for a boycott of the 2016 Oscars for failing to recognize minority achievements, the board voted to make "historic" changes to its membership. The Academy stated that by 2020 it would double its number of women and minority members. While the Academy has addressed a higher profile for African-Americans, it has yet to raise the profile of other people of color artists, in front of and behind the camera.


text: In 2020, "Parasite" became the first non-English language film to win Best Picture. In June 2022, Bill Kramer was named the CEO of the Academy. Also in 2022, Janet Yang was elected as the first Asian American President of the Academy.


text: The Academy's numerous and diverse operations are housed in three facilities in the Los Angeles area: the headquarters building in Beverly Hills, which was constructed specifically for the Academy, and two Centers for Motion Picture Study – one in Beverly Hills, the other in Hollywood – which were existing structures restored and transformed to contain the Academy's Library, Film Archive and other departments and programs.


text: The Academy Headquarters Building in Beverly Hills once housed two galleries that were open free to the public. The Grand Lobby Gallery and the Fourth Floor Gallery offered changing exhibits related to films, film-making and film personalities. These galleries have since been closed in preparation for the opening of the Academy Museum of Motion Pictures in 2020.


text: The building includes the Samuel Goldwyn Theater, which seats 1,012, and was designed to present films at maximum technical accuracy, with state-of-the-art projection equipment and sound system. The theater is busy year-round with the Academy's public programming, members-only screenings, movie premieres and other special activities (including the live television broadcast of the Academy Awards nominations announcement every January). The building once housed the Academy Little Theater, a 67-seat screening facility, but this was converted to additional office space in a building remodel.


text: The Pickford Center for Motion Picture Study, located in central Hollywood and named for legendary actress and Academy founder Mary Pickford, houses several Academy departments, including the Academy Film Archive, the Science and Technology Council, Student Academy Awards and Grants, and the Nicholl Fellowships in Screenwriting. The building, originally dedicated on August 18, 1948, is the oldest surviving structure in Hollywood that was designed specifically with television in mind. Additionally, it is the location of the Linwood Dunn Theater, which seats 286 people.


text: The Fairbanks Center for Motion Picture Study is located at 333 S. La Cienega Boulevard in Beverly Hills. It is home to the Academy's Margaret Herrick Library, a world-renowned, non-circulating reference and research collection devoted to the history and development of the motion picture as an art form and an industry. Established in 1928, the library is open to the public and used year-round by students, scholars, historians and industry professionals. The library is named for Margaret Herrick, the Academy's first librarian who also played a major role in the Academy's first televised broadcast, helping to turn the Oscar ceremony into a major annual televised event.


text: The building itself was built in 1928, where it was originally built to be a water treatment plant for Beverly Hills. Its "bell tower" held water-purifying hardware.


text: The Academy Museum of Motion Pictures, a Los Angeles museum, is the newest facility associated with the Academy. Its scheduled opening was on September 30, 2021, and it contains over of galleries, exhibition spaces, movie theaters, educational areas, and special event spaces.


text: The Academy also has a New York City-based East Coast showcase theater, the Academy Theater at Lighthouse International. The 220-seat venue was redesigned in 2011 by renowned theater designer Theo Kalomirakis, including an extensive installation of new audio and visual equipment. The theater is in the East 59th Street headquarters of the non-profit vision loss organization, Lighthouse International. In July 2015, it was announced that the Academy was forced to move out, due to Lighthouse International selling the property the theater was in.


text: Membership in the Academy is by invitation only. Invitation comes from the Board of Governors. Membership eligibility may be achieved by earning a competitive Oscar nomination, or by the sponsorship of two current Academy members from the same branch to which the candidate seeks admission.


text: New membership proposals are considered annually in the spring. Press releases announce the names of those who have recently been invited to join. Membership in the Academy does not expire, even if a member struggles later in his or her career.


text: Academy membership is divided into 17 branches, representing different disciplines in motion pictures. Members may not belong to more than one branch. Members whose work does not fall within one of the branches may belong to a group known as "Members at Large". Members at Large have all the privileges of branch membership except for representation on the Board. Associate members are those closely allied to the industry but not actively engaged in motion picture production. They are not represented on the Board and do not vote on Academy Awards.


text: According to a February 2012 study conducted by the "Los Angeles Times" (sampling over 5,000 of its 5,765 members), the Academy at that time was 94% white, 77% male, 86% age 50 or older, and had a median age of 62. A third of members were previous winners or nominees of Academy Awards themselves. Of the Academy's 54-member Board of Governors, 25 are female.


text: On June 29, 2016, a paradigm shift began in the Academy's selection process, resulting in a new class comprising 46% women and 41% people of color. The effort to diversify the Academy was led by social activist and Broadway Black managing-editor April Reign. Reign created the Twitter hashtag #OscarsSoWhite as a means of criticizing the dearth of non-white nominees for the 2015 Academy Awards. Though the hashtag drew widespread media attention, the Academy remained obstinate on the matter of adopting a resolution that would make demonstrable its efforts to increase diversity. With the 2016 Academy Awards, many, including April Reign, were dismayed by the Academy's indifference about representation and inclusion, as the 2016 nominees were once again entirely white. April Reign revived #OscarsSoWhite, and renewed her campaign efforts, which included multiple media appearances and interviews with reputable news outlets. As a result of Reign's campaign, the discourse surrounding representation and recognition in film spread beyond the United States and became a global discussion . Faced with mounting pressure to expand the Academy membership, the Academy capitulated and instituted new policies to ensure that future Academy membership invitations would better represent the demographics of modern film-going audiences. The A2020 initiative was announced in January 2016 to double the number of women and people of color in membership by 2020.


text: Members are able to see many new films for free at the Samuel Goldwyn Theater within two weeks of their debut, and sometimes before release; in addition, some of the screeners are available through iTunes to its members.


text: Five people are known to have been expelled from the Academy. Academy officials acknowledge that other members have been expelled in the past, most for selling their Oscar tickets, but no numbers are available.


text: , the Board of Governors consists of 54 governors: three governors from each of the 17 Academy branches and three governors-at-large. The Makeup Artists and Hairstylists Branch, created in 2006, had only one governor until July 2013. The Casting Directors Branch, created in 2013, elected its first three governors in Fall 2013.


text: The Board of Governors is responsible for corporate management, control, and general policies. The Board of Governors also appoints a CEO and a COO to supervise the administrative activities of the Academy.


text: From the original formal banquet, which was hosted by Louis B. Mayer in 1927, everyone invited became a founder of the Academy:


text: Presidents are elected for one-year terms and may not be elected for more than four consecutive terms.


title: Flour

text: Flour is a powder made by grinding raw grains, roots, beans, nuts, or seeds. Flours are used to make many different foods. Cereal flour, particularly wheat flour, is the main ingredient of bread, which is a staple food for many cultures. Corn flour has been important in Mesoamerican cuisine since ancient times and remains a staple in the Americas. Rye flour is a constituent of bread in central and northern Europe.


title: Flour

text: Cereal flour consists either of the endosperm, germ, and bran together (whole-grain flour) or of the endosperm alone (refined flour). "Meal" is either differentiable from flour as having slightly coarser particle size (degree of comminution) or is synonymous with flour; the word is used both ways. For example, the word "cornmeal" often connotes a grittier texture whereas corn flour connotes fine powder, although there is no codified dividing line.


title: Flour

text: The CDC has cautioned not to eat raw flour doughs or batters. Raw flour can contain bacteria like "E. coli" and needs to be cooked like other foods.


title: Flour

text: The English word "flour" is originally a variant of the word "flower", and both words derive from the Old French "fleur" or "flour", which had the literal meaning "blossom", and a figurative meaning "the finest". The phrase "fleur de farine" meant "the finest part of the meal", since flour resulted from the elimination of coarse and unwanted matter from the grain during milling. "Meal" is either differentiable from flour as having slightly coarser particle size (degree of comminution) or is synonymous with flour; the word is used both ways. For example, the word "cornmeal" often connotes a grittier texture whereas corn flour connotes fine powder, although there is no codified dividing line.


title: Flour

text: Corn flour has been important in Mesoamerican cuisine since ancient times and remains a staple in the Americas. Rye flour is a constituent of bread in central and northern Europe. Archaeological evidence for making flour (wheat seeds crushed between simple millstones) dates to at least 6000 BC. In 2018, archaeologists reported finding evidence of bread making at Shubayqa 1, a Natufian hunter-gatherer site more than 14,000 years old in northwest Jordan. The Romans were the first to grind seeds on cone mills. In 1786, at the beginning of the Industrial Era, the first steam-powered flour mill, Albion Mills, Southwark, was completed in London. In the 1930s, some flour began to be enriched with iron, niacin, thiamine and riboflavin. In the 1940s, mills started to enrich flour and folic acid was added to the list in the 1990s.


title: Flour

text: An important problem of the industrial revolution was the preservation of flour. Transportation distances and a relatively slow distribution system collided with natural shelf life. The reason for the limited shelf life is the fatty acids of the germ, which react from the moment they are exposed to oxygen. This occurs when grain is milled; the fatty acids oxidize and flour starts to become rancid. Depending on climate and grain quality, this process takes six to nine months. In the late 19th century, this process was too short for an industrial production and distribution cycle. As vitamins, micronutrients and amino acids were completely or relatively unknown in the late 19th century, removing the germ was an effective solution. Without the germ, flour cannot become rancid. Degermed flour became standard. Degermation started in densely populated areas and took approximately one generation to reach the countryside.


title: Flour

text: Heat-processed flour is flour where the germ is first separated from the endosperm and bran, then processed with steam, dry heat or microwave and blended into flour again.


title: Flour

text: Milling of flour is accomplished by grinding grain between stones or steel wheels. Today, "stone-ground" usually means that the grain has been ground in a mill in which a revolving stone wheel turns over a stationary stone wheel, vertically or horizontally with the grain in between.


title: Flour

text: Roller mills soon replaced stone grist mills as the production of flour has historically driven technological development, as attempts to make gristmills more productive and less labor-intensive led to the watermill and windmill. These terms are now applied more broadly to uses of water and wind power for purposes other than milling. More recently, the Unifine mill, an impact-type mill, was developed in the mid-20th century.


title: Flour

text: Modern farm equipment allows livestock farmers to do some or all of their own milling when it comes time to convert their own grain crops to coarse meal for livestock feed. This capability is economically important because the profit margins are often thin enough in commercial farming that saving expenses is vital to staying in business.


title: Flour

text: Flour contains a high proportion of starches, which are a subset of complex carbohydrates also known as polysaccharides. The kinds of flour used in cooking include all-purpose flour (known as plain outside North America), self-rising flour, and cake flour including bleached flour. The higher the protein content the harder and stronger the flour, and the more it will produce crusty or chewy breads. The lower the protein the softer the flour, which is better for cakes, cookies, and pie crusts. Cereal flour consists either of the endosperm, germ, and bran together (whole-grain flour) or of the endosperm alone (refined flour).


title: Flour

text: "Bleached flour" is "refined" flour with a chemical whitening (bleaching) agent added. "Refined" flour has had the germ and bran, containing much of the nutritional fibre and vitamins, removed and is often referred to as "white flour".


title: Flour

text: Bleached flour is artificially aged using a "bleaching" agent, a "maturing" agent, or both. A bleaching agent affects the carotenoids responsible for the natural colour of the flour; a "maturing" agent also affects gluten development. A maturing agent may either strengthen or weaken gluten development.


title: Flour

text: "Cake flour" in particular is nearly always chlorinated. At least one flour labeled "unbleached cake flour blend" (marketed by King Arthur Flour) is not bleached, and the protein content is much higher than typical cake flour at about 9.4% protein (cake flour is usually around 6% to 8%). According to King Arthur, this flour is a blend of a more finely milled unbleached wheat flour and cornstarch, which makes a better result than unbleached wheat flour alone (cornstarch blended with all-purpose flour is commonly substituted for cake flour when the latter is unavailable). The end product, however, is denser than would result from lower-protein, chlorinated cake flour.


title: Flour

text: All bleaching and maturing agents (with the possible exception of ascorbic acid) have been banned in the United Kingdom.


title: Flour

text: Bromination of flour in the US has fallen out of favor, and while it is not yet actually banned anywhere, few retail flours available to the home baker are bromated anymore.


title: Flour

text: Many varieties of flour packaged specifically for commercial bakeries are still bromated. Retail bleached flour marketed to the home baker is now treated mostly with either peroxidation or chlorine gas. Current information from Pillsbury is that their varieties of bleached flour are treated both with benzoyl peroxide and chlorine gas. Gold Medal states that their bleached flour is treated either with benzoyl peroxide or chlorine gas, but no way exists to tell which process has been used when buying the flour at the grocery store.


title: Flour

text: During the process of making flour, specifically as a result of the bleaching process, nutrients are lost. Some of these nutrients may be replaced during refining – the result is known as "enriched" flour.


title: Flour

text: Cake flour is the lowest in gluten protein content, with 6-7% (5-8% from second source) protein to produce minimal binding so the cake "crumbles" easily.


title: Flour

text: Pastry flour has the second-lowest gluten protein content, with 7.5-9.5% (8-9% from second source) protein to hold together with a bit more strength than cakes, but still produce flaky crusts rather than hard or crispy ones.


title: Flour

text: All-purpose, or "AP flour", or plain flour is medium in gluten protein content at 9.5-11.5% (10-12% from second source) protein content. It has adequate protein content for many bread and pizza bases, though bread flour and special 00 grade Italian flour are often preferred for these purposes, respectively, especially by artisan bakers. Some biscuits are also prepared using this type of flour. "Plain" refers not only to AP flour's middling gluten content but also to its lack of any added leavening agent (as in self-rising flour).


title: Flour

text: Bread flour is typically made from red hard wheat planted in the fall and harvested in the spring (winter wheat). Hard wheat is high in gluten, a protein that makes dough stretchy. Hard wheat is 11.5-13.5% (12-14% from second source) protein. The increased protein binds to the flour to entrap carbon dioxide released by the yeast fermentation process, resulting in a better rise and chewier texture.


title: Flour

text: Hard is a general term for flours with high gluten protein content, commonly refers to extra strong flour, with 13.5-16% (or 14-15% from some sources) protein (16% is a theoretically possible protein content). This flour may be used where a recipe adds ingredients that require the dough to be extra strong to hold together in their presence, or when strength is needed for constructions of bread (e.g., some centerpiece displays).


title: Flour

text: Gluten flour is refined gluten protein, or a theoretical 100% protein (though practical refining never achieves a full 100%). It is used to strengthen flour as needed. For example, adding approximately one teaspoon per cup of AP flour gives the resulting mix the protein content of bread flour. It is commonly added to whole grain flour recipes to overcome the tendency of greater fiber content to interfere with gluten development, needed to give the bread better rising (gas holding) qualities and chew.


title: Flour

text: Unbleached flour is simply flour that has not undergone bleaching and therefore does not have the color of "white" flour. An example is graham flour, whose namesake, Sylvester Graham, was against using bleaching agents, which he considered unhealthy.


title: Flour

text: In English-speaking countries, self-raising (or self-rising) flour is commercially available with chemical leavening agents already in the mix. In America, it is also likely to be pre-salted; in Britain this is not the case. The added ingredients are evenly distributed throughout the flour, which aids a consistent rise in baked goods. This flour is generally used for preparing sponge cakes, scones, muffins, etc. It was invented by Henry Jones and patented in 1845. If a recipe calls for self-raising flour, and this is not available, the following substitution is possible:


title: Flour

text: Wheat is the grain most commonly used to make flour. Certain varieties may be referred to as "clean" or "white". Flours contain differing levels of the protein gluten. "Strong flour" or "hard flour" has a higher gluten content than "weak" or "soft" flour. "Brown" and wholemeal flours may be made of hard or soft wheat.


title: Flour

text: When flours do not contain gluten, they are suitable for people with gluten-related disorders, such as coeliac disease, non-celiac gluten sensitivity or wheat allergy sufferers, among others. Contamination with gluten-containing cereals can occur during grain harvesting, transporting, milling, storing, processing, handling and/or cooking.


title: Flour

text: Flour also can be made from soybeans, arrowroot, taro, cattails, acorns, manioc, quinoa, and other non-cereal foodstuffs.


title: Flour

text: In some markets, the different available flour varieties are labeled according to the ash mass that remains after a sample is incinerated in a laboratory oven (typically at or , see international standards ISO 2171 and ICC 104/1). This is an easily verified indicator for the fraction of the whole grain remains in the flour, because the mineral content of the starchy endosperm is much lower than that of the outer parts of the grain. Flour made from all parts of the grain (extraction rate: 100%) leaves about ash or more per dry flour. Plain white flour with an extraction rate of 50–60% leaves about .


title: Flour

text: In the United States and the United Kingdom, no numbered standardized flour types are defined, and the ash mass is only rarely given on the label by flour manufacturers. However, the legally required standard nutrition label specifies the protein content of the flour, which is also a way for comparing the extraction rates of different available flour types.


title: Flour

text: In general, as the extraction rate of the flour increases, so do both the protein and the ash content. However, as the extraction rate approaches 100% (whole meal), the protein content drops slightly, while the ash content continues to rise.


title: Flour

text: The following table shows some typical examples of how protein and ash content relate to each other in wheat flour:


title: Flour

text: This table is only a rough guideline for converting bread recipes. Since flour types are not standardized in many countries, the numbers may differ between manufacturers. There is no French type corresponding to the lowest ash residue in the table. The closest is French Type 45.


title: Flour

text: There is no official Chinese name corresponding to the highest ash residue in the table. Usually such products are imported from Japan and the Japanese name Zenryufun (全粒粉) is used, or it is called QuanMaiMianFen (全麥麵粉).


title: Flour

text: It is possible to determine ash content from some US manufacturers. However, US measurements are based on wheat with a 14% moisture content. Thus, a US flour with 0.48% ash would approximate a French Type 55.


title: Flour

text: Other measurable properties of flour as used in baking can be determined using a variety of specialized instruments, such as the farinograph.


title: Flour

text: Flour dust suspended in air is explosive—as is any mixture of a finely powdered flammable substance with air ("see" dust explosion). Some devastating explosions have occurred at flour mills, including an explosion in 1878 at the Washburn "A" Mill in Minneapolis that killed 22 people.


title: Flour

text: The CDC has cautioned not to eat raw flour doughs or batters. Raw flour can contain bacteria like "E. coli" and needs to be cooked like other foods.


title: Flour

text: Bread, pasta, crackers, many cakes, and many other foods are made using flour. Wheat flour is also used to make a roux as a base for thickening gravy and sauces.


title: Flour

text: Cornstarch is a principal ingredient used to thicken many puddings or desserts, and is the main ingredient in packaged custard.


title: Quantum superposition

text: Quantum superposition is a fundamental principle of quantum mechanics. It states that, much like waves in classical physics, any two (or more) quantum states can be added together ("superposed") and the result will be another valid quantum state; and conversely, that every quantum state can be represented as a sum of two or more other distinct states. Mathematically, it refers to a property of solutions to the Schrödinger equation; since the Schrödinger equation is linear, any linear combination of solutions will also be a solution(s)


title: Quantum superposition

text: An example of a physically observable manifestation of the wave nature of quantum systems is the interference peaks from an electron beam in a double-slit experiment. The pattern is very similar to the one obtained by diffraction of classical waves.


title: Quantum superposition

text: Another example is a quantum logical qubit state, as used in quantum information processing, which is a quantum superposition of the "basis states" formula_1 and formula_2.


title: Quantum superposition

text: Here formula_1 is the Dirac notation for the quantum state that will always give the result 0 when converted to classical logic by a measurement. Likewise formula_2 is the state that will always convert to 1. Contrary to a classical bit that can only be in the state corresponding to 0 or the state corresponding to 1, a qubit may be in a superposition of both states. This means that the probabilities of measuring 0 or 1 for a qubit are in general neither 0.0 nor 1.0, and multiple measurements made on qubits in identical states will not always give the same result.


title: Quantum superposition

text: The principle of quantum superposition states that if a physical system may be in one of many configurations—arrangements of particles or fields—then the most general state is a combination of all of these possibilities, where the amount in each configuration is specified by a complex number.


title: Quantum superposition

text: The general principle of superposition of quantum mechanics applies to the states [that are theoretically possible without mutual interference or contradiction] ... of any one dynamical system. It requires us to assume that between these states there exist peculiar relationships such that whenever the system is definitely in one state we can consider it as being partly in each of two or more other states. The original state must be regarded as the result of a kind of superposition of the two or more new states, in a way that cannot be conceived on classical ideas. Any state may be considered as the result of a superposition of two or more other states, and indeed in an infinite number of ways. Conversely, any two or more states may be superposed to give a new state...


title: Quantum superposition

text: The non-classical nature of the superposition process is brought out clearly if we consider the superposition of two states, "A" and "B", such that there exists an observation which, when made on the system in state "A", is certain to lead to one particular result, "a" say, and when made on the system in state "B" is certain to lead to some different result, "b" say. What will be the result of the observation when made on the system in the superposed state? The answer is that the result will be sometimes "a" and sometimes "b", according to a probability law depending on the relative weights of "A" and "B" in the superposition process. It will never be different from both "a" and "b" [i.e., either "a" or "b"]. "The intermediate character of the state formed by superposition thus expresses itself through the probability of a particular result for an observation being intermediate between the corresponding probabilities for the original states, not through the result itself being intermediate between the corresponding results for the original states."


title: Quantum superposition

text: Anton Zeilinger, referring to the prototypical example of the double-slit experiment, has elaborated regarding the creation and destruction of quantum superposition:


title: Quantum superposition

text: "[T]he superposition of amplitudes ... is only valid if there is no way to know, even in principle, which path the particle took. It is important to realize that this does not imply that an observer actually takes note of what happens. It is sufficient to destroy the interference pattern, if the path information is accessible in principle from the experiment or even if it is dispersed in the environment and beyond any technical possibility to be recovered, but in principle still ‘‘out there.’’ The absence of any such information is "the essential criterion" for quantum interference to appear.


title: Quantum superposition

text: For an equation describing a physical phenomenon, the superposition principle states that a combination of solutions to a linear equation is also a solution of it. When this is true the equation is said to obey the superposition principle. Thus, if state vectors , and each solve the linear equation on ψ, then would also be a solution, in which each is a coefficient. The Schrödinger equation is linear, so quantum mechanics follows this.


title: Quantum superposition

text: For example, consider an electron with two possible configurations: up and down. This describes the physical system of a qubit.


title: Quantum superposition

text: is the most general state. But these coefficients dictate probabilities for the system to be in either configuration. The probability for a specified configuration is given by the square of the absolute value of the coefficient. The probabilities must add to 1, since the electron must be in one of those two states.


title: Quantum superposition

text: Continuing with this example, if a particle can be in state  up and  down, it can also be in a state where it is an amount up and an amount down.


title: Quantum superposition

text: In this, the probability for up is formula_11. The probability for down is formula_12. Note that formula_13.


title: Quantum superposition

text: In the description, only the relative size of the different components matter, and their angle to each other on the complex plane. This is usually stated by declaring that two states which are a multiple of one another are the same as far as the description of the situation is concerned. Either of these describe the same state for any nonzero formula_14


title: Quantum superposition

text: The fundamental law of quantum mechanics is that the evolution is linear, meaning that if state A turns into A′ and B turns into B′ after 10 seconds, then after 10 seconds the superposition formula_16 turns into a mixture of A′ and B′ with the same coefficients as A and B.


title: Quantum superposition

text: In illustration, a particle can have any position, so that there are different configurations which have any value of the position . These are written:


title: Quantum superposition

text: The principle of superposition guarantees that there are states which are arbitrary superpositions of all the positions with complex coefficients:


title: Quantum superposition

text: This sum is defined only if the index  is discrete. If the index is over formula_22, then the sum is replaced by an integral. The quantity formula_23 is called the wavefunction of the particle.


title: Quantum superposition

text: If we consider a qubit with both position and spin, the state is a superposition of all possibilities for both:


title: Quantum superposition

text: The configuration space of a quantum mechanical system cannot be worked out without some physical knowledge. The input is usually the allowed different classical configurations, but without the duplication of including both position and momentum.


title: Quantum superposition

text: A pair of particles can be in any combination of pairs of positions. A state where one particle is at position x and the other is at position y is written formula_25. The most general state is a superposition of the possibilities:


title: Quantum superposition

text: The description of the two particles is much larger than the description of one particle—it is a function in twice the number of dimensions. This is also true in probability, when the statistics of two random variables are correlated. If two particles are uncorrelated, the probability distribution for their joint position is a product of the probability of finding one at one position and the other at the other position:


title: Quantum superposition

text: This means that the wave function formula_28 of the system can be represented as a product of the wave functions formula_29 and formula_30 of its parts:


title: Quantum superposition

text: In 1927, Heitler and London, attempted to quantitatively mechanically calculate the ground steady state of the H molecule. The calculations were based on the quantum superposition of the two hydrogen atoms that make up the system - H molecule. The success of this attempt became the basis for all further development of covalent bond.


title: Quantum superposition

text: In probability theory there is a similar principle. If a system has a probabilistic description, this description gives the probability of any configuration, and given any two different configurations, there is a state which is partly this and partly that, with positive real number coefficients, the probabilities, which say how much of each there is.


title: Quantum superposition

text: For example, if we have a probability distribution for where a particle is, it is described by the "state"


title: Quantum superposition

text: Where formula_33 is the probability density function, a positive number that measures the probability that the particle will be found at a certain location.


title: Quantum superposition

text: The evolution equation is also linear in probability, for fundamental reasons. If the particle has some probability for going from position "x" to "y", and from "z" to "y", the probability of going to "y" starting from a state which is half-"x" and half-"z" is a half-and-half mixture of the probability of going to "y" from each of the options. This is the principle of linear superposition in probability.


title: Quantum superposition

text: Quantum mechanics is different, because the numbers can be positive or negative. While the complex nature of the numbers is just a doubling, if you consider the real and imaginary parts separately, the sign of the coefficients is important. In probability, two different possible outcomes always add together, so that if there are more options to get to a point "z", the probability always goes up. In quantum mechanics, different possibilities can cancel.


title: Quantum superposition

text: In probability theory with a finite number of states, the probabilities can always be multiplied by a positive number to make their sum equal to one. For example, if there is a three state probability system:


title: Quantum superposition

text: The geometry of the state space is a revealed to be a triangle. In general it is a simplex. There are special points in a triangle or simplex corresponding to the corners, and these points are those where one of the probabilities is equal to 1 and the others are zero. These are the unique locations where the position is known with certainty.


title: Quantum superposition

text: In a quantum mechanical system with three states, the quantum mechanical wavefunction is a superposition of states again, but this time twice as many quantities with no restriction on the sign:


title: Quantum superposition

text: rescaling the variables so that the sum of the squares is 1, the geometry of the space is revealed to be a high-dimensional sphere


title: Quantum superposition

text: A sphere has a large amount of symmetry, it can be viewed in different coordinate systems or bases. So unlike a probability theory, a quantum theory has a large number of different bases in which it can be equally well described. The geometry of the phase space can be viewed as a hint that the quantity in quantum mechanics which corresponds to the probability is the "absolute square" of the coefficient of the superposition.