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🔗 Tang Ping
Tang ping (Chinese: 躺平; pinyin: tǎng píng; lit. 'lying flat') is a lifestyle choice and social protest movement in China by some young people who reject societal pressures on hard work or even overwork (such as the 996 working hour system, which is generally regarded as a rat race with ever diminishing returns), and instead choose to "lie down flat and get over the beatings" via a low-desire, more indifferent attitude towards life. Novelist Liao Zenghu described "lying flat" as a resistance movement, and The New York Times called it part of a nascent Chinese counterculture. It has also been compared to the Great Resignation that began in America (and the western world) around the same time.
Unlike the hikikomori in Japan (who are socially withdrawn), these young Chinese people who subscribe to "lying flat" are not socially isolated, but merely choose to lower their professional and economic ambitions and simplify their goals, still being fiscally productive for their own essential needs, and prioritize psychological health over economic materialism.
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- "Tang ping, social protest movement to “lie down flat and get over the beatings”" | 2022-01-10 | 35 Upvotes 5 Comments
- "Tang Ping" | 2021-11-20 | 17 Upvotes 4 Comments
🔗 Clashes between web and X11 colors in the CSS color scheme
In computing, on the X Window System, X11 color names are represented in a simple text file, which maps certain strings to RGB color values. It was traditionally shipped with every X11 installation, hence the name, and is usually located in <X11root>/lib/X11/rgb.txt. The web colors list is descended from it but differs for certain color names.
Color names are not standardized by Xlib or the X11 protocol. The list does not show continuity either in selected color values or in color names, and some color triplets have multiple names. Despite this, graphic designers and others got used to them, making it practically impossible to introduce a different list. In earlier releases of X11 (prior to the introduction of Xcms), server implementors were encouraged to modify the RGB values in the reference color database to account for gamma correction.
As of X.Org Release 7.4 rgb.txt is no longer included in the roll up release, and the list is built directly into the server. The optional module xorg/app/rgb contains the stand-alone rgb.txt file.
The list first shipped with X10 release 3 (X10R3) on 7 June 1986, having been checked into RCS by Jim Gettys in 1985. The same list was in X11R1 on 18 September 1987. Approximately the full list as is available today shipped with X11R4 on 29 January 1989, with substantial additions by Paul Ravelling (who added colors based on Sinclair Paints samples), John C. Thomas (who added colors based on a set of 72 Crayola crayons he had on hand) and Jim Fulton (who reconciled contributions to produce the X11R4 list). The project was running DEC VT240 terminals at the time, so would have worked to that device.
In some applications multipart names are written with spaces, in others joined together, often in camel case. They are usually matched insensitive of case and the X Server source code contains spaced aliases for most entries; this article uses spaces and uppercase initials except where variants with spaces are not specified in the actual code.
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- "Clashes between web and X11 colors in the CSS color scheme" | 2025-07-13 | 66 Upvotes 28 Comments
🔗 Trivialism
Trivialism (from Latin trivialis 'found everywhere') is the logical theory that all statements (also known as propositions) are true and that all contradictions of the form "p and not p" (e.g. the ball is red and not red) are true. In accordance with this, a trivialist is a person who believes everything is true.
In classical logic, trivialism is in direct violation of Aristotle's law of noncontradiction. In philosophy, trivialism is considered by some to be the complete opposite of skepticism. Paraconsistent logics may use "the law of non-triviality" to abstain from trivialism in logical practices that involve true contradictions.
Theoretical arguments and anecdotes have been offered for trivialism to contrast it with theories such as modal realism, dialetheism and paraconsistent logics.
Discussed on
- "Trivialism" | 2021-06-07 | 28 Upvotes 12 Comments
🔗 1989 California Medfly Attack
In 1989, a sudden invasion of Mediterranean fruit flies (Ceratitis capitata, "medflies") appeared in California and began devastating crops. Scientists were puzzled and said that the sudden appearance of the insects "defies logic", and some speculated "biological terrorists" were responsible. Analysis suggested that an outside hand played a role in the dense infestation.
A person or group calling itself "The Breeders" took responsibility for the bioterrorist attack, as financial retaliation for the environmental damage caused by the state's Malathion aerial spraying; the group's members were never identified. Subsequently, three months after "The Breeders" announced the medfly release, the state ended its decade-long Malathion program and sought alternate ways to handle destructive insects.
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- "1989 California Medfly Attack" | 2020-05-29 | 213 Upvotes 99 Comments
🔗 Connes Embedding Problem
Connes' embedding problem, formulated by Alain Connes in the 1970s, is a major problem in von Neumann algebra theory. During that time, the problem was reformulated in several different areas of mathematics. Dan Voiculescu developing his free entropy theory found that Connes' embedding problem is related to the existence of microstates. Some results of von Neumann algebra theory can be obtained assuming positive solution to the problem. The problem is connected to some basic questions in quantum theory, which led to the realization that it also has important implications in computer science.
The problem admits a number of equivalent formulations. Notably, it is equivalent to the following long standing problems:
- Kirchberg's QWEP conjecture in C*-algebra theory
- Tsirelson's problem in quantum information theory
- The predual of any (separable) von Neumann algebra is finitely representable in the trace class.
In January 2020, Ji, Natarajan, Vidick, Wright, and Yuen announced a result in quantum complexity theory that implies a negative answer to Connes' embedding problem. However, an error was discovered in September 2020 in an earlier result they used; a new proof avoiding the earlier result was published as a preprint in September. A broad outline was published in Communications of the ACM in November 2021, and an article explaining the connection between MIP*=RE and the Connes Embedding Problem appeared in October 2022.
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- "Connes Embedding Problem" | 2026-02-12 | 19 Upvotes 2 Comments
🔗 Band-e Kaisar – “Caesar's dam”
The Band-e Kaisar (Persian: بند قیصر, "Caesar's dam"), Pol-e Kaisar ("Caesar's bridge"), Bridge of Valerian or Shadirwan was an ancient arch bridge in Shushtar, Iran, and the first in the country to combine it with a dam. Built by the Sassanids, using Roman prisoners of war as workforce, in the 3rd century AD on Sassanid order, it was also the most eastern example of Roman bridge design and Roman dam, lying deep in Persian territory. Its dual-purpose design exerted a profound influence on Iranian civil engineering and was instrumental in developing Sassanid water management techniques.
The approximately 500 m long overflow dam over the Karun, Iran's most effluent river, was the core structure of the Shushtar Historical Hydraulic System (سازههای آبی شوشتر) from which the city derived its agricultural productivity, and which has been designated by the UNESCO as Iran's 10th World Heritage Site in 2009. The arched superstructure carried across the important road between Pasargadae and the Sassanid capital Ctesiphon. Many times repaired in the Islamic period, the dam bridge remained in use until the late 19th century.
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- "Band-e Kaisar – “Caesar's dam”" | 2016-01-03 | 16 Upvotes 2 Comments
🔗 The Analytical Language of John Wilkins
"The Analytical Language of John Wilkins" (Spanish: "El idioma analítico de John Wilkins") is a short essay by Argentine writer Jorge Luis Borges, first printed in La Nación on 8 February 1942 and subsequently published in Otras Inquisiciones (1937–1952). It is a critique of the English natural philosopher and writer John Wilkins's proposal for a universal language and of the representational capacity of language generally. In it, Borges imagines a bizarre and whimsical (and fictional) Chinese taxonomy later quoted by Michel Foucault, David Byrne, and others.
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- "The Analytical Language of John Wilkins" | 2024-04-25 | 37 Upvotes 8 Comments
- "The Analytical Language of John Wilkins" | 2023-02-06 | 26 Upvotes 1 Comments
🔗 Cherenkov radiation – Faster then light in water
Cherenkov radiation (; Russian: Эффект Вавилова — Черенкова, Vavilov-Cherenkov effect) is electromagnetic radiation emitted when a charged particle (such as an electron) passes through a dielectric medium at a speed greater than the phase velocity (speed of propagation of a wavefront in a medium) of light in that medium. A classic example of Cherenkov radiation is the characteristic blue glow of an underwater nuclear reactor. Its cause is similar to the cause of a sonic boom, the sharp sound heard when faster-than-sound movement occurs. The phenomenon is named after Soviet physicist Pavel Cherenkov.
🔗 Project Orion (nuclear propulsion)
Project Orion was a study of a spacecraft intended to be directly propelled by a series of explosions of atomic bombs behind the craft (nuclear pulse propulsion). Early versions of this vehicle were proposed to take off from the ground (with significant associated nuclear fallout); later versions were presented for use only in space. Six non-nuclear tests were conducted using models. The project was eventually abandoned for multiple reasons such as the Partial Test Ban Treaty which banned nuclear explosions in space as well as concerns over nuclear fallout.
The idea of rocket propulsion by combustion of explosive substance was first proposed by Russian explosives expert Nikolai Kibalchich in 1881, and in 1891 similar ideas were developed independently by German engineer Hermann Ganswindt. Robert A. Heinlein mentions powering spaceships with nuclear bombs in his 1940 short story "Blowups Happen." Real life proposals of nuclear propulsion were first made by Stanislaw Ulam in 1946, and preliminary calculations were made by F. Reines and Ulam in a Los Alamos memorandum dated 1947. The actual project, initiated in 1958, was led by Ted Taylor at General Atomics and physicist Freeman Dyson, who at Taylor's request took a year away from the Institute for Advanced Study in Princeton to work on the project.
The Orion concept offered high thrust and high specific impulse, or propellant efficiency, at the same time. The unprecedented extreme power requirements for doing so would be met by nuclear explosions, of such power relative to the vehicle's mass as to be survived only by using external detonations without attempting to contain them in internal structures. As a qualitative comparison, traditional chemical rockets—such as the Saturn V that took the Apollo program to the Moon—produce high thrust with low specific impulse, whereas electric ion engines produce a small amount of thrust very efficiently. Orion would have offered performance greater than the most advanced conventional or nuclear rocket engines then under consideration. Supporters of Project Orion felt that it had potential for cheap interplanetary travel, but it lost political approval over concerns with fallout from its propulsion.
The Partial Test Ban Treaty of 1963 is generally acknowledged to have ended the project. However, from Project Longshot to Project Daedalus, Mini-Mag Orion, and other proposals which reach engineering analysis at the level of considering thermal power dissipation, the principle of external nuclear pulse propulsion to maximize survivable power has remained common among serious concepts for interstellar flight without external power beaming and for very high-performance interplanetary flight. Such later proposals have tended to modify the basic principle by envisioning equipment driving detonation of much smaller fission or fusion pellets, in contrast to Project Orion's larger nuclear pulse units (full nuclear bombs) based on less speculative technology.
To Mars by A-Bomb: The Secret History of Project Orion was a 2003 BBC documentary film about the project.
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- "Project Orion" | 2023-03-16 | 126 Upvotes 69 Comments
- "Project Orion (nuclear propulsion)" | 2015-02-10 | 32 Upvotes 11 Comments