Random Articles (Page 49)
Have a deep view into what people are curious about.
π Hacker Koan
The Jargon File is a glossary and usage dictionary of slang used by computer programmers. The original Jargon File was a collection of terms from technical cultures such as the MIT AI Lab, the Stanford AI Lab (SAIL) and others of the old ARPANET AI/LISP/PDP-10 communities, including Bolt, Beranek and Newman, Carnegie Mellon University, and Worcester Polytechnic Institute. It was published in paperback form in 1983 as The Hacker's Dictionary (edited by Guy Steele), revised in 1991 as The New Hacker's Dictionary (ed. Eric S. Raymond; third edition published 1996).
The concept of the file began with the Tech Model Railroad Club (TMRC) that came out of early PDP-1 and TX-0 hackers in the 1950s, where the term hacker emerged and the ethic, philosophies and some of the nomenclature emerged.
Discussed on
- "Hacker Koan" | 2014-03-23 | 15 Upvotes 15 Comments
- "Hacker Koan" | 2010-07-31 | 50 Upvotes 7 Comments
π Railway Time
Railway time was the standardised time arrangement first applied by the Great Western Railway in England in November 1840, the first recorded occasion when different local mean times were synchronised and a single standard time applied. The key goals behind introducing railway time were to overcome the confusion caused by having non-uniform local times in each town and station stop along the expanding railway network and to reduce the incidence of accidents and near misses, which were becoming more frequent as the number of train journeys increased.
Railway time was progressively taken up by all railway companies in Great Britain over the following seven years. The schedules by which trains were organised and the time station clocks displayed were brought in line with the local mean time for London or "London Time", the time set at Greenwich by the Royal Observatory, which was already widely known as Greenwich Mean Time (GMT).
The development of railway networks in North America in the 1850s, India in around 1860, and in Europe, prompted the introduction of standard time influenced by geography, industrial development, and political governance.
The railway companies sometimes faced concerted resistance from local people who refused to adjust their public clocks to bring them into line with London Time. As a consequence, two different times would be displayed in the town and in use, with the station clocks and the times published in train timetables differing by several minutes from that on other clocks. Despite this early reluctance, railway time rapidly became adopted as the default time across the whole of Great Britain, although it took until 1880 for the government to legislate on the establishment of a single standard time and a single time zone for the country.
Some contemporary commentators referred to the influence of railway time on encouraging greater precision in daily tasks and the demand for punctuality.
Discussed on
- "Railway Time" | 2023-10-07 | 94 Upvotes 45 Comments
π Baumol Effect
Baumol's cost disease (or the Baumol effect) is the rise of salaries in jobs that have experienced no or low increase of labor productivity, in response to rising salaries in other jobs that have experienced higher labor productivity growth. This pattern seemingly goes against the theory in classical economics in which real wage growth is closely tied to labor productivity changes. The phenomenon was described by William J. Baumol and William G. Bowen in the 1960s.
The rise of wages in jobs without productivity gains is from the requirement to compete for employees with jobs that have experienced gains and so can naturally pay higher salaries, just as classical economics predicts. For instance, if the retail sector pays its managers 19th-century-style salaries, the managers may decide to quit to get a job at an automobile factory, where salaries are higher because of high labor productivity. Thus, managers' salaries are increased not by labor productivity increases in the retail sector but by productivity and corresponding wage increases in other industries.
Discussed on
- "Baumol Effect" | 2020-10-17 | 123 Upvotes 99 Comments
- "Baumol Effect" | 2019-07-15 | 91 Upvotes 62 Comments
- "Baumol's Cost Disease: Why Artists are Always Poor" | 2009-12-02 | 39 Upvotes 14 Comments
π Decline in Insect Populations
An increasing number of scientific studies are reporting substantial declines in insect populations worldwide. Most commonly, the declines involve reductions in abundance, though in some cases entire species are going extinct. The declines are far from uniform. In some localities, there have been reports of increases in overall insect population, and some types of insects appear to be increasing in abundance across the world.
Some of the insects most affected include bees, butterflies, moths, beetles, dragonflies and damselflies. Anecdotal evidence has been offered of much greater apparent abundance of insects in the 20th century; recollections of the windscreen phenomenon are an example.
Possible causes are similar to other biodiversity loss, with studies identifying: habitat destruction, including intensive agriculture; the use of pesticides (particularly insecticides); urbanization, and industrialization; introduced species; and climate change. Not all insect orders are affected in the same way; many groups are the subject of limited research, and comparative figures from earlier decades are often not available.
In response to the reported declines, increased insect related conservation measures have been launched. In 2018 the German government initiated an "Action Programme for Insect Protection", and in 2019 a group of 27 British entomologists and ecologists wrote an open letter calling on the research establishment in the UK "to enable intensive investigation of the real threat of ecological disruption caused by insect declines without delay".
π Mauryan Polish
Mauryan polish describes one of the frequent characteristics of architecture and sculptures of the Maurya Empire in India (325 to 185 BCE), which gives a very smooth and shiny surface to the stone material, generally of sandstone or granite. Mauryan polish is found especially in the Ashoka Pillars as well as in some constructions like the Barabar Caves. The technique did not end with the empire, but continued to be "used on occasion up to the first or second century A.D.", although the presence of the polish sometimes complicates dating, as with the Didarganj Yakshi. According to the archaeologist John Marshall: the "extraordinary precision and accuracy which characterizes all Mauryan works, and which has never, we venture to say, been surpassed even by the finest workmanship on Athenian buildings".
Discussed on
- "Mauryan Polish" | 2021-05-22 | 67 Upvotes 26 Comments
π Kaktovik numerals β A base-20 number system that is visually easy too
Kaktovik numerals are a featural positional numeral system created by Alaskan IΓ±upiat.
Arabic numeral notation, which was designed for a base-10 numeral system, is inadequate for the Inuit languages, which use a base-20 numeral system. Students in Kaktovik, Alaska, invented a base-20 numeral notation in 1994 to rectify this issue, and this system spread among the Alaskan IΓ±upiat and has been considered in other countries where Inuit languages are spoken.
The image at right shows the digits 0 to 19. Twenty is written as a one and a zero (\Ι€), forty as a two and a zero (VΙ€), four hundred as a one and two zeros (\Ι€Ι€), eight hundred as a two and two zeros (VΙ€Ι€), etc.
Discussed on
- "Kaktovik Numerals" | 2023-01-25 | 180 Upvotes 70 Comments
- "Kaktovik numerals β A base-20 number system that is visually easy too" | 2021-03-04 | 39 Upvotes 2 Comments
π Zero to the Power of Zero
Zero to the power of zero, denoted by 00, is a mathematical expression with no agreed-upon value. The most common possibilities are 1 or leaving the expression undefined, with justifications existing for each, depending on context. In algebra and combinatorics, the generally agreed upon value isΒ 00 = 1, whereas in mathematical analysis, the expression is sometimes left undefined. Computer programs also have differing ways of handling this expression.
Discussed on
- "Zero to the Power of Zero" | 2020-05-14 | 38 Upvotes 27 Comments
π Capgras Delusion
Capgras delusion is a psychiatric disorder in which a person holds a delusion that a friend, spouse, parent, or other close family member (or pet) has been replaced by an identical impostor. It is named after Joseph Capgras (1873β1950), a French psychiatrist.
The Capgras delusion is classified as a delusional misidentification syndrome, a class of delusional beliefs that involves the misidentification of people, places, or objects. It can occur in acute, transient, or chronic forms. Cases in which patients hold the belief that time has been "warped" or "substituted" have also been reported.
The delusion most commonly occurs in individuals diagnosed with paranoid schizophrenia but has also been seen in brain injury, dementia with Lewy bodies, and other dementia. It presents often in individuals with a neurodegenerative disease, particularly at an older age. It has also been reported as occurring in association with diabetes, hypothyroidism, and migraine attacks. In one isolated case, the Capgras delusion was temporarily induced in a healthy subject by the drug ketamine. It occurs more frequently in females, with a female to male ratio of approximately 3 to 2.
Discussed on
- "Capgras Delusion" | 2010-03-30 | 16 Upvotes 3 Comments
π Utility Monster
The utility monster is a thought experiment in the study of ethics created by philosopher Robert Nozick in 1974 as a criticism of utilitarianism.
Discussed on
- "Utility Monster" | 2020-05-14 | 59 Upvotes 67 Comments
π Ulam Spiral
The Ulam spiral or prime spiral is a graphical depiction of the set of prime numbers, devised by mathematician StanisΕaw Ulam in 1963 and popularized in Martin Gardner's Mathematical Games column in Scientific American a short time later. It is constructed by writing the positive integers in a square spiral and specially marking the prime numbers.
Ulam and Gardner emphasized the striking appearance in the spiral of prominent diagonal, horizontal, and vertical lines containing large numbers of primes. Both Ulam and Gardner noted that the existence of such prominent lines is not unexpected, as lines in the spiral correspond to quadratic polynomials, and certain such polynomials, such as Euler's prime-generating polynomial x2βββxβ+β41, are believed to produce a high density of prime numbers. Nevertheless, the Ulam spiral is connected with major unsolved problems in number theory such as Landau's problems. In particular, no quadratic polynomial has ever been proved to generate infinitely many primes, much less to have a high asymptotic density of them, although there is a well-supported conjecture as to what that asymptotic density should be.
In 1932, more than thirty years prior to Ulam's discovery, the herpetologist Laurence Klauber constructed a triangular, non-spiral array containing vertical and diagonal lines exhibiting a similar concentration of prime numbers. Like Ulam, Klauber noted the connection with prime-generating polynomials, such as Euler's.
Discussed on
- "Ulam Spiral" | 2021-08-06 | 64 Upvotes 19 Comments
- "Ulam Spiral" | 2016-06-06 | 71 Upvotes 13 Comments
- "Ulam spiral" | 2013-11-09 | 90 Upvotes 27 Comments