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πŸ”— YIMBY Movement

πŸ”— Architecture πŸ”— Urban studies and planning πŸ”— Effective Altruism

The YIMBY movement (short for "yes in my back yard") is a pro-infrastructure development movement mostly focusing on public housing policy, real estate development, public transportation, and pedestrian safety in transportation planning, in contrast and in opposition to the NIMBY ("not in my back yard") movement that generally opposes most forms of urban development in order to maintain the status quo. As a popular organized movement in the United States, it began in the San Francisco Bay Area in the 2010s amid a major housing affordability crisis and has subsequently become a potent political force in state and local politics across the United States.

The YIMBY position supports increasing the supply of housing within cities where housing costs have escalated to unaffordable levels. They have also supported infrastructure development projects like improving housing development (especially for affordable housing or trailer parks), high-speed rail lines, homeless shelters, day cares, schools, universities and colleges, bike lanes, and transportation planning that promotes pedestrian safety infrastructure. YIMBYs often seek rezoning that would allow denser housing to be produced or the repurposing of obsolete buildings, such as shopping malls, into housing. Some YIMBYs have also supported public-interest projects like clean energy or alternative transport.

The YIMBY movement has supporters across the political spectrum, including left-leaning adherents who believe housing production is a social justice issue, free-market libertarian proponents who think the supply of housing should not be regulated by the government, and environmentalists who believe land use reform will slow down exurban development into natural areas. YIMBYs argue cities can be made increasingly affordable and accessible by building more infill housing,:β€Š1β€Š and that greenhouse gas emissions will be reduced by denser cities.

πŸ”— Hundredth monkey effect

πŸ”— Skepticism πŸ”— Primates

The hundredth monkey effect is a hypothetical phenomenon in which a new behaviour or idea is said to spread rapidly by unexplained means from one group to all related groups once a critical number of members of one group exhibit the new behaviour or acknowledge the new idea.

One of the primary factors in the promulgation of the story is that many authors quote secondary, tertiary or post-tertiary sources which have themselves misrepresented the original observations.

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πŸ”— Lambda lifting

πŸ”— Computing

Lambda lifting is a meta-process that restructures a computer program so that functions are defined independently of each other in a global scope. An individual "lift" transforms a local function into a global function. It is a two step process, consisting of;

  • Eliminating free variables in the function by adding parameters.
  • Moving functions from a restricted scope to broader or global scope.

The term "lambda lifting" was first introduced by Thomas Johnsson around 1982 and was historically considered as a mechanism for implementing functional programming languages. It is used in conjunction with other techniques in some modern compilers.

Lambda lifting is not the same as closure conversion. It requires all call sites to be adjusted (adding extra arguments to calls) and does not introduce a closure for the lifted lambda expression. In contrast, closure conversion does not require call sites to be adjusted but does introduce a closure for the lambda expression mapping free variables to values.

The technique may be used on individual functions, in code refactoring, to make a function usable outside the scope in which it was written. Lambda lifts may also be repeated, in order to transform the program. Repeated lifts may be used to convert a program written in lambda calculus into a set of recursive functions, without lambdas. This demonstrates the equivalence of programs written in lambda calculus and programs written as functions. However it does not demonstrate the soundness of lambda calculus for deduction, as the eta reduction used in lambda lifting is the step that introduces cardinality problems into the lambda calculus, because it removes the value from the variable, without first checking that there is only one value that satisfies the conditions on the variable (see Curry's paradox).

Lambda lifting is expensive on processing time for the compiler. An efficient implementation of lambda lifting is O ( n 2 ) {\displaystyle O(n^{2})} on processing time for the compiler.

In the untyped lambda calculus, where the basic types are functions, lifting may change the result of beta reduction of a lambda expression. The resulting functions will have the same meaning, in a mathematical sense, but are not regarded as the same function in the untyped lambda calculus. See also intensional versus extensional equality.

The reverse operation to lambda lifting is lambda dropping.

Lambda dropping may make the compilation of programs quicker for the compiler, and may also increase the efficiency of the resulting program, by reducing the number of parameters, and reducing the size of stack frames. However it makes a function harder to re-use. A dropped function is tied to its context, and can only be used in a different context if it is first lifted.

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πŸ”— Karatsuba Algorithm

πŸ”— Computing πŸ”— Mathematics πŸ”— Computing/Software πŸ”— Computing/Computer science

The Karatsuba algorithm is a fast multiplication algorithm. It was discovered by Anatoly Karatsuba in 1960 and published in 1962. It reduces the multiplication of two n-digit numbers to at most n log 2 ⁑ 3 β‰ˆ n 1.58 {\displaystyle n^{\log _{2}3}\approx n^{1.58}} single-digit multiplications in general (and exactly n log 2 ⁑ 3 {\displaystyle n^{\log _{2}3}} when n is a power of 2). It is therefore faster than the classical algorithm, which requires n 2 {\displaystyle n^{2}} single-digit products. For example, the Karatsuba algorithm requires 310 = 59,049 single-digit multiplications to multiply two 1024-digit numbers (n = 1024 = 210), whereas the classical algorithm requires (210)2 = 1,048,576 (a speedup of 17.75 times).

The Karatsuba algorithm was the first multiplication algorithm asymptotically faster than the quadratic "grade school" algorithm. The Toom–Cook algorithm (1963) is a faster generalization of Karatsuba's method, and the SchΓΆnhage–Strassen algorithm (1971) is even faster, for sufficiently large n.

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πŸ”— The Sokal Hoax

πŸ”— Skepticism πŸ”— History of Science πŸ”— Sociology

The Sokal affair, also called the Sokal hoax, was a scholarly publishing sting perpetrated by Alan Sokal, a physics professor at New York University and University College London. In 1996, Sokal submitted an article to Social Text, an academic journal of postmodern cultural studies. The submission was an experiment to test the journal's intellectual rigor and, specifically, to investigate whether "a leading North American journal of cultural studiesβ€”whose editorial collective includes such luminaries as Fredric Jameson and Andrew Rossβ€”[would] publish an article liberally salted with nonsense if (a) it sounded good and (b) it flattered the editors' ideological preconceptions".

The article, "Transgressing the Boundaries: Towards a Transformative Hermeneutics of Quantum Gravity", was published in the Social Text spring/summer 1996 "Science Wars" issue. It proposed that quantum gravity is a social and linguistic construct. At that time, the journal did not practice academic peer review and it did not submit the article for outside expert review by a physicist. Three weeks after its publication in May 1996, Sokal revealed in Lingua Franca that the article was a hoax.

The hoax sparked a debate about the scholarly merit of commentary on the physical sciences by those in the humanities; the influence of postmodern philosophy on social disciplines in general; academic ethics, including whether Sokal was wrong to deceive the editors and readers of Social Text; and whether Social Text had exercised appropriate intellectual rigor.

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πŸ”— List of Generation Z Slang

πŸ”— Internet culture πŸ”— Lists πŸ”— Languages

This is a list of slang used by Generation Z (Gen Z), generally those born between the late 1990s and the late 2000s in the Western world.

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πŸ”— Tunnel of Eupalinos

πŸ”— Architecture πŸ”— Greece

The Tunnel of Eupalinos or Eupalinian aqueduct (Greek: Ευπαλίνιον ΟŒΟΟ…Ξ³ΞΌΞ±, romanized:Β Efpalinion orygma) is a tunnel of 1,036Β m (3,399Β ft) length running through Mount Kastro in Samos, Greece, built in the 6th century BC to serve as an aqueduct. The tunnel is the second known tunnel in history which was excavated from both ends (Ancient Greek: ἀμφίστομον, romanized:Β amphistomon, "having two openings"), and the first with a geometry-based approach in doing so. Today it is a popular tourist attraction.

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πŸ”— Red Mercury

πŸ”— Military history πŸ”— Military history/Military science, technology, and theory πŸ”— Military history/Weaponry πŸ”— Elements πŸ”— Military history/Cold War

Red mercury is purportedly a substance of uncertain composition used in the creation of nuclear weapons, as well as other weapons systems. Because of the great secrecy surrounding the development and manufacture of nuclear weapons, there is no proof that red mercury exists. However, all samples of alleged "red mercury" analyzed in the public literature have proven to be well-known, common red substances of no interest to weapons makers.

Red mercury is therefore considered a hoax, perpetrated by con artists who sought to take advantage of gullible buyers on the black market for arms. There have been reports of "red mercury" on the international black markets since 1979, but the hoax seems to have been most common in the early 1990s, with very high asking prices.

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πŸ”— Cryptomnesia

πŸ”— Psychology

Cryptomnesia occurs when a forgotten memory returns without its being recognized as such by the subject, who believes it is something new and original. It is a memory bias whereby a person may falsely recall generating a thought, an idea, a tune, a name, or a joke, not deliberately engaging in plagiarism but rather experiencing a memory as if it were a new inspiration.

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