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πŸ”— Abelian sandpile model

πŸ”— Mathematics πŸ”— Physics πŸ”— Systems πŸ”— Systems/Dynamical systems

The Abelian sandpile model, also known as the Bak–Tang–Wiesenfeld model, was the first discovered example of a dynamical system displaying self-organized criticality. It was introduced by Per Bak, Chao Tang and Kurt Wiesenfeld in a 1987 paper.

The model is a cellular automaton. In its original formulation, each site on a finite grid has an associated value that corresponds to the slope of the pile. This slope builds up as "grains of sand" (or "chips") are randomly placed onto the pile, until the slope exceeds a specific threshold value at which time that site collapses transferring sand into the adjacent sites, increasing their slope. Bak, Tang, and Wiesenfeld considered process of successive random placement of sand grains on the grid; each such placement of sand at a particular site may have no effect, or it may cause a cascading reaction that will affect many sites.

The model has since been studied on the infinite lattice, on other (non-square) lattices, and on arbitrary graphs (including directed multigraphs). It is closely related to the dollar game, a variant of the chip-firing game introduced by Biggs.

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πŸ”— Elite Overproduction

πŸ”— Sociology

Elite overproduction is a concept developed by Peter Turchin, which describes the condition of a society which is producing too many potential elite-members relative to its ability to absorb them into the power structure. This, he hypothesizes, is a cause for social instability, as those left out of power feel aggrieved by their relatively low socioeconomic status.

Turchin said that this situation explained social disturbances during the late Roman empire and the French Wars of Religion, and predicted in 2010 that this situation would cause social unrest in the United States of America during the 2020s. According to Turchin and Jack Goldstone, periods of political instability have throughout human history been due to the purely self-interested behavior of the elite. When the economy faced a surge in the workforce, which exerted a downward pressure on wages, the elite generally kept much of the wealth generated to themselves, resisting taxation and income redistribution. In the face of intensifying competition, they also sought to restrict the window of opportunity, to preserve their power and status for their descendants. These actions exacerbated inequality, a key driver of sociopolitical turbulence due to the proneness of the relatively well-off to radicalism. Widespread progressive political beliefs among university graduates, for instance, can be due to widespread underemployment rather than from exposure to progressive ideas or experiences during their studies.

In the case of the United States, by the 2010s, it became clear that the cost of higher education has ballooned over the previous three to four decadesβ€”faster than inflation, in factβ€”thanks to growing demand. For this prediction, Turchin used current data and the structural-demographic theory, a mathematical model of how population changes affect the behavior of the state, the elite, and the commons, created by Jack Goldstone. Goldstone himself predicted using his model that in the twenty-first century, the United States would elect a national populist leader. Elite overproduction has been cited as a root cause of political tension in the U.S., as so many well-educated Millennials are either unemployed, underemployed, or otherwise not achieving the high status they expect. Even then, the nation continued to produce excess PhD holders before the COVID-19 pandemic hit, especially in the humanities and social sciences, for which employment prospects were dim. Moreover, according to projections by the U.S. Census Bureau, the share of people in their 20s continued to grow till the end of the 2010s, meaning the youth bulge would likely not fade away before the 2020s. As such the gap between the supply and demand in the labor market would likely not fall before then, and falling or stagnant wages generate sociopolitical stress.

In the United Kingdom, there was simply not enough working-class Britons disenchanted with the status quo to support the Brexit movement, which was also buoyed by many highly educated voters.

However, Turchin's model cannot foretell precisely how a crisis will unfold; it can only yield probabilities. Turchin likened this to the accumulation of deadwood in a forest over many years, paving the way for a cataclysmic forest fire later on. It is possible to predict a massive conflagration, but not what causes it.

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πŸ”— Lenin was a mushroom

πŸ”— Soviet Union πŸ”— Russia πŸ”— Russia/mass media in Russia πŸ”— Television πŸ”— Russia/history of Russia

Lenin was a mushroom (Russian: Π›Π΅Π½ΠΈΠ½ β€” Π³Ρ€ΠΈΠ±) was a highly influential televised hoax by Soviet musician Sergey Kuryokhin and reporter Sergey Sholokhov. It was first broadcast on 17 May 1991 on Leningrad Television.

The hoax took the form of an interview on the television program Pyatoe Koleso (The Fifth Wheel). In the interview, Kuryokhin, impersonating a historian, narrated his findings that Vladimir Lenin consumed large quantities of psychedelic mushrooms and eventually became a mushroom himself. Kuryokhin arrived at his conclusion through a long series of logical fallacies and appeals to the authority of various "sources" (such as Carlos Castaneda, the Massachusetts Institute of Technology, and Konstantin Tsiolkovsky), creating the illusion of a reasoned and plausible logical chain.

The timing of the hoax played a large role in its success, coming as it did during the Glasnost period when the ebbing of censorship in the Soviet Union led to many revelations about the country's history, often presented in sensational form. Furthermore, Soviet television had, up to that point, been regarded by its audience as conservative in style and content. As a result, a large number of Soviet citizens (one estimate puts the number at 11,250,000 audience members) took the deadpan "interview" at face value, in spite of the absurd claims presented.

Sholokhov has said that perhaps the most notable result of the show was an appeal by a group of party members to the Leningrad Regional Committee of the CPSU to clarify the veracity of Kuryokhin's claim. According to Sholokhov, in response to the request one of the top regional functionaries stated that "Lenin could not have been a mushroom" because "a mammal cannot be a plant." Modern taxonomy classifies mushrooms as fungi, a separate kingdom from plants.

The incident has served as a watershed moment in Soviet (and Russian) culture and has often been used as proof of the gullibility of the masses.

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πŸ”— Kirkbride Plan

πŸ”— Architecture πŸ”— Psychology πŸ”— Sociology πŸ”— Correction and Detention Facilities πŸ”— Urban studies and planning πŸ”— Hospitals

The Kirkbride Plan was a system of mental asylum design advocated by American psychiatrist Thomas Story Kirkbride (1809–1883) in the mid-19th century. The asylums built in the Kirkbride design, often referred to as Kirkbride Buildings (or simply Kirkbrides), were constructed during the mid-to-late-19th century in the United States. The structural features of the hospitals as designated by Kirkbride were contingent on his theories regarding the healing of the mentally ill, in which environment and exposure to natural light and air circulation were crucial. The hospitals built according to the Kirkbride Plan would adopt various architectural styles, but had in common the "bat wing" style floor plan, housing numerous wings that sprawl outward from the center.

The first hospital designed under the Kirkbride Plan was the Trenton State Hospital in Trenton, New Jersey, constructed in 1848. Throughout the remainder of the nineteenth century, numerous psychiatric hospitals were designed under the Kirkbride Plan across the United States. By the twentieth century, popularity of the design had waned, largely due to the economic pressures of maintaining the immense facilities, as well as contestation of Kirkbride's theories amongst the medical community.

Numerous Kirkbride structures still exist, though many have been demolished or partially-demolished and repurposed. At least 30 of the original Kirkbride buildings have been registered with the National Register of Historic Places in the United States, either directly or through their location on hospital campuses or in historic districts.

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πŸ”— Fast inverse square root

πŸ”— Video games πŸ”— Computer science πŸ”— Mathematics

Fast inverse square root, sometimes referred to as Fast InvSqrt() or by the hexadecimal constant 0x5F3759DF, is an algorithm that estimates ​1β„βˆšx, the reciprocal (or multiplicative inverse) of the square root of a 32-bit floating-point number x in IEEE 754 floating-point format. This operation is used in digital signal processing to normalize a vector, i.e., scale it to length 1. For example, computer graphics programs use inverse square roots to compute angles of incidence and reflection for lighting and shading. The algorithm is best known for its implementation in 1999 in the source code of Quake III Arena, a first-person shooter video game that made heavy use of 3D graphics. The algorithm only started appearing on public forums such as Usenet in 2002 or 2003. At the time, it was generally computationally expensive to compute the reciprocal of a floating-point number, especially on a large scale; the fast inverse square root bypassed this step.

The algorithm accepts a 32-bit floating-point number as the input and stores a halved value for later use. Then, treating the bits representing the floating-point number as a 32-bit integer, a logical shift right by one bit is performed and the result subtracted from the number 0x5F3759DF, which is a floating point representation of an approximation of √2127. This results in the first approximation of the inverse square root of the input. Treating the bits again as a floating-point number, it runs one iteration of Newton's method, yielding a more precise approximation.

The algorithm was originally attributed to John Carmack, but an investigation showed that the code had deeper roots in both the hardware and software side of computer graphics. Adjustments and alterations passed through both Silicon Graphics and 3dfx Interactive, with Gary Tarolli's implementation for the SGI Indigo as the earliest known use. It is not known how the constant was originally derived, though investigation has shed some light on possible methods.

With subsequent hardware advancements, especially the x86 SSE instruction rsqrtss, this method is not generally applicable to modern computing, though it remains an interesting example both historically and for more limited machines.

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πŸ”— Toyetic

πŸ”— Film πŸ”— Marketing & Advertising πŸ”— Film/Filmmaking πŸ”— Media πŸ”— Toys πŸ”— Games

Toyetic is a term referring to the suitability of a media property, such as a cartoon or movie, for merchandising tie-in lines of licensed toys, games and novelties. The term is attributed to Bernard Loomis, a toy development executive for Kenner Toys, in discussing the opportunities for marketing the film Close Encounters of the Third Kind, telling its producer Steven Spielberg that the movie wasn't "toyetic" enough, leading Loomis towards acquiring the lucrative license for the upcoming Star Wars properties.

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πŸ”— Borax

πŸ”— Chemicals πŸ”— Occupational Safety and Health πŸ”— Food and drink πŸ”— Rocks and minerals πŸ”— Chemicals/Chemicals worklist

Borax, also known as sodium borate, sodium tetraborate, or disodium tetraborate, is an important boron compound, a mineral, and a salt of boric acid. Powdered borax is white, consisting of soft colorless crystals that dissolve in water. A number of closely related minerals or chemical compounds that differ in their crystal water content are referred to as borax, and the word is usually used to refer to the octahydrate. Commercially sold borax is partially dehydrated.

Borax is a component of many detergents, cosmetics, and enamel glazes. It is used to make buffer solutions in biochemistry, as a fire retardant, as an anti-fungal compound, in the manufacture of fiberglass, as a flux in metallurgy, neutron-capture shields for radioactive sources, a texturing agent in cooking, as a cross-linking agent in Slime, as an alkali in photographic developers, as a precursor for other boron compounds, and along with its inverse, boric acid, is useful as an insecticide.

In artisanal gold mining, borax is sometimes used as part of a process (as a flux) meant to eliminate the need for toxic mercury in the gold extraction process, although it cannot directly replace mercury. Borax was reportedly used by gold miners in parts of the Philippines in the 1900s.

Borax was first discovered in dry lake beds in Tibet and was imported via the Silk Road to the Arabian Peninsula in the 8th century AD. Borax first came into common use in the late 19th century when Francis Marion Smith's Pacific Coast Borax Company began to market and popularize a large variety of applications under the 20 Mule Team Borax trademark, named for the method by which borax was originally hauled out of the California and Nevada deserts.

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πŸ”— Daphne Caruana Galizia

πŸ”— Biography πŸ”— Women writers πŸ”— Biography/arts and entertainment πŸ”— Journalism πŸ”— Malta

Daphne Anne Caruana Galizia (nΓ©e Vella; 26 August 1964 – 16 October 2017) was a Maltese writer, journalist, blogger and anti-corruption activist, who reported on political events in Malta. In particular, she focused on investigative journalism, reporting on government corruption, nepotism, patronage, allegations of money laundering, links between Malta's online gambling industry and organized crime, Malta's citizenship-by-investment scheme, and payments from the government of Azerbaijan. Caruana Galizia's national and international reputation was built on her regular reporting of misconduct by Maltese politicians and politically exposed persons.

Caruana Galizia continued to publish articles for decades, despite intimidation and threats, libel suits and other lawsuits. She was arrested by the Malta Police Force on two occasions. Caruana Galizia's investigations were published via her personal blog Running Commentary, which she set up in 2008. She was a regular columnist with The Sunday Times of Malta and later The Malta Independent. Her blog consisted of investigative reporting and commentary, some of which was regarded as personal attacks on individuals, leading to a series of legal battles. In 2016 and 2017, she revealed controversially sensitive information and allegations relating to a number of Maltese politicians and the Panama Papers scandal.

On 16 October 2017, Caruana Galizia was killed close to her home when a car bomb was detonated inside her vehicle, attractingΒ widespread local and international condemnation of the attack. In December 2017, three men were arrested in connection with the car bomb attack. Police arrested Yorgen Fenech, the owner of the Dubai-based company 17 Black, on his yacht on 20 November 2019 in connection with her murder.

In April 2018, an international consortium of 45 journalists published The Daphne Project, a collaboration to complete her investigative work. The GUE/NGL Award for Journalists, Whistleblowers & Defenders of the Right to Information was established in 2018 in honour of Galizia.

πŸ”— Ramanujan's Lost Notebook

πŸ”— Mathematics πŸ”— India πŸ”— India/Tamil Nadu

Ramanujan's lost notebook is the manuscript in which the Indian mathematician Srinivasa Ramanujan recorded the mathematical discoveries of the last year (1919–1920) of his life. Its whereabouts were unknown to all but a few mathematicians until it was rediscovered by George Andrews in 1976, in a box of effects of G. N. Watson stored at the Wren Library at Trinity College, Cambridge. The "notebook" is not a book, but consists of loose and unordered sheets of paper described as "more than one hundred pages written on 138 sides in Ramanujan's distinctive handwriting. The sheets contained over six hundred mathematical formulas listed consecutively without proofs."

George Andrews and Bruce C. BerndtΒ (2005, 2009, 2012, 2013, 2018) have published several books in which they give proofs for Ramanujan's formulas included in the notebook. Berndt says of the notebook's discovery: "The discovery of this 'Lost Notebook' caused roughly as much stir in the mathematical world as the discovery of Beethoven’s tenth symphony would cause in the musical world."

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