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๐ Beflix (Bell Labs Flicks)
BEFLIX is the name of the first embedded domain-specific language for computer animation, invented by Ken Knowlton at Bell Labs in 1963. The name derives from a combination of Bell Flicks. Ken Knowlton used BEFLIX to create animated films for educational and engineering purposes. He also collaborated with the artist Stan Vanderbeek at Bell Labs to create a series of computer-animated films called Poemfields between 1966 and 1969.
BEFLIX was developed on the IBM 7090 mainframe computer using a Stromberg-Carlson SC4020 microfilm recorder for output. The programming environment targeted by BEFLIX consisted of a FORTRAN II implementation with FORTRAN II Assembly Program (FAP) macros. The first version of BEFLIX was implemented through the FAP macro facility. A later version targeting FORTRAN IV resembled a more traditional subroutine library and lost some of the unique flavor to the language.
Pixels are produced by writing characters to the screen of the microfilm recorder with a defocused electron beam. The SC4020 used a charactron tube to expose microfilm. In BEFLIX, the electron beam is defocused to draw pixels as blurred character shapes. Characters are selected to create a range of grayscale values for pixels. The microfilm recorder is not connected directly to the 7090, but communicates through magnetic tape. BEFLIX writes the magnetic tape output on the 7090 and the film recorder reads the tape to create the film output. BEFLIX also supports a preview mode where selected frames of the output are written to the line printer.
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- "Beflix (Bell Labs Flicks)" | 2024-10-18 | 16 Upvotes 5 Comments
๐ Firefox Wikipedia Page Contains Recursive Screenshot of Itself
Mozilla Firefox or simply Firefox, is a free and open-source web browser developed by the Mozilla Foundation and its subsidiary, the Mozilla Corporation. Firefox uses the Gecko rendering engine to display web pages, which implements current and anticipated web standards. In 2017, Firefox began incorporating new technology under the code name Quantum to promote parallelism and a more intuitive user interface. Firefox is available for Windows 7 or Windows 10, macOS, and Linux. Its unofficial ports are available for various Unix and Unix-like operating systems including FreeBSD, OpenBSD, NetBSD, illumos, and Solaris Unix. Firefox is also available for Android and iOS. However, the iOS version uses the WebKit layout engine instead of Gecko due to platform requirements, as with all other iOS web browsers. An optimized version of Firefox is also available on the Amazon Fire TV, as one of the two main browsers available with Amazon's Silk Browser.
Firefox was created in 2002 under the code name "Phoenix" by the Mozilla community members who desired a standalone browser, rather than the Mozilla Application Suite bundle. During its beta phase, Firefox proved to be popular with its testers and was praised for its speed, security, and add-ons compared to Microsoft's then-dominant Internet Explorerย 6. Firefox was released on November 9, 2004, and challenged Internet Explorer's dominance with 60ย million downloads within nine months. Firefox is the spiritual successor of Netscape Navigator, as the Mozilla community was created by Netscape in 1998 before their acquisition by AOL.
Firefox usage share grew to a peak of 32.21% at the end of 2009, with Firefox 3.5 overtaking Internet Explorer 7, although not all versions of Internet Explorer as a whole. Usage then declined in competition with Google Chrome. As of Augustย 2021, according to StatCounter, Firefox has 7.62% usage share as a "desktop" web browser, making it the fourth-most popular web browser after Google Chrome (68.76%), Safari (9.7%) and Microsoft Edge (8.1%), while its usage share across all platforms is lower at 3.45% in third place (after Google Chrome with 65.27% and Safari with 18.34%).
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- "Firefox Wikipedia Page Contains Recursive Screenshot of Itself" | 2021-10-06 | 74 Upvotes 5 Comments
๐ Program Synthesis
In computer science, program synthesis is the task to construct a program that provably satisfies a given high-level formal specification. In contrast to program verification, the program is to be constructed rather than given; however, both fields make use of formal proof techniques, and both comprise approaches of different degrees of automation. In contrast to automatic programming techniques, specifications in program synthesis are usually non-algorithmic statements in an appropriate logical calculus.
The primary application of program synthesis is to relieve the programmer of the burden of writing correct, efficient code that satisfies a specification. However, program synthesis also has applications to superoptimization and inference of loop invariants.
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- "Program Synthesis" | 2024-04-13 | 54 Upvotes 19 Comments
๐ Alcubierre drive
The Alcubierre drive, Alcubierre warp drive, or Alcubierre metric (referring to metric tensor) is a speculative idea based on a solution of Einstein's field equations in general relativity as proposed by Mexican theoretical physicist Miguel Alcubierre, by which a spacecraft could achieve apparent faster-than-light travel if a configurable energy-density field lower than that of vacuum (that is, negative mass) could be created.
Rather than exceeding the speed of light within a local reference frame, a spacecraft would traverse distances by contracting space in front of it and expanding space behind it, resulting in effective faster-than-light travel. Objects cannot accelerate to the speed of light within normal spacetime; instead, the Alcubierre drive shifts space around an object so that the object would arrive at its destination faster than light would in normal space without breaking any physical laws.
Although the metric proposed by Alcubierre is consistent with the Einstein field equations, construction of such a drive is not necessarily possible. The proposed mechanism of the Alcubierre drive implies a negative energy density and therefore requires exotic matter. So if exotic matter with the correct properties cannot exist, then the drive could not be constructed. At the close of his original article, however, Alcubierre argued (following an argument developed by physicists analyzing traversable wormholes) that the Casimir vacuum between parallel plates could fulfill the negative-energy requirement for the Alcubierre drive.
Another possible issue is that, although the Alcubierre metric is consistent with Einstein's equations, general relativity does not incorporate quantum mechanics. Some physicists have presented arguments to suggest that a theory of quantum gravity (which would incorporate both theories) would eliminate those solutions in general relativity that allow for backwards time travel (see the chronology protection conjecture) and thus make the Alcubierre drive invalid.
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- "Alcubierre drive" | 2018-08-12 | 166 Upvotes 125 Comments
๐ Portable soup
Portable soup was a kind of dehydrated food used in the 18th and 19th centuries. It was a precursor of meat extract and bouillon cubes, and of industrially dehydrated food. It is also known as pocket soup or veal glew. It is a cousin of the glace de viande of French cooking. It was long a staple of seamen and explorers, for it would keep for many months or even years. In this context, it was a filling and nutritious dish. Portable soup of less extended vintage was, according to the 1881 Household Cyclopedia, "exceedingly convenient for private families, for by putting one of the cakes in a saucepan with about a quart of water, and a little salt, a basin of good broth may be made in a few minutes."
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- "Portable soup" | 2016-02-09 | 17 Upvotes 1 Comments
๐ Mathematical Universe Hypothesis
In physics and cosmology, the mathematical universe hypothesis (MUH), also known as the ultimate ensemble theory, is a speculative "theory of everything" (TOE) proposed by cosmologist Max Tegmark.
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- "Mathematical Universe Hypothesis" | 2023-06-30 | 13 Upvotes 3 Comments
๐ Keynesian beauty contest
A Keynesian beauty contest is a concept developed by John Maynard Keynes and introduced in Chapter 12 of his work, The General Theory of Employment, Interest and Money (1936), to explain price fluctuations in equity markets.
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- "Keynesian beauty contest" | 2011-06-12 | 81 Upvotes 27 Comments
๐ Entropic Gravity
Entropic gravity, also known as emergent gravity, is a theory in modern physics that describes gravity as an entropic forceโa force with macro-scale homogeneity but which is subject to quantum-level disorderโand not a fundamental interaction. The theory, based on string theory, black hole physics, and quantum information theory, describes gravity as an emergent phenomenon that springs from the quantum entanglement of small bits of spacetime information. As such, entropic gravity is said to abide by the second law of thermodynamics under which the entropy of a physical system tends to increase over time.
At its simplest, the theory holds that when gravity becomes vanishingly weakโlevels seen only at interstellar distancesโit diverges from its classically understood nature and its strength begins to decay linearly with distance from a mass.
Entropic gravity provides the underlying framework to explain Modified Newtonian Dynamics, or MOND, which holds that at a gravitational acceleration threshold of approximately 1.2ร10โ10ย m/s2, gravitational strength begins to vary inversely (linearly) with distance from a mass rather than the normal inverse-square law of the distance. This is an exceedingly low threshold, measuring only 12ย trillionths gravity's strength at earth's surface; an object dropped from a height of one meter would fall for 36 hours were earth's gravity this weak. It is also 3,000 times less than exists at the point where Voyager 1 crossed our solar system's heliopause and entered interstellar space.
The theory claims to be consistent with both the macro-level observations of Newtonian gravity as well as Einstein's theory of general relativity and its gravitational distortion of spacetime. Importantly, the theory also explains (without invoking the existence of dark matter and its accompanying math featuring new free parameters that are tweaked to obtain the desired outcome) why galactic rotation curves differ from the profile expected with visible matter.
The theory of entropic gravity posits that what has been interpreted as unobserved dark matter is the product of quantum effects that can be regarded as a form of positive dark energy that lifts the vacuum energy of space from its ground state value. A central tenet of the theory is that the positive dark energy leads to a thermal-volume law contribution to entropy that overtakes the area law of anti-de Sitter space precisely at the cosmological horizon.
The theory has been controversial within the physics community but has sparked research and experiments to test its validity.
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- "Entropic Gravity" | 2019-09-02 | 193 Upvotes 111 Comments
๐ List of assets owned by The Walt Disney Company
The following is a list of assets owned and operated by The Walt Disney Company, unless otherwise indicated.
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- "List of assets owned by The Walt Disney Company" | 2020-02-25 | 17 Upvotes 5 Comments
๐ Belyayev's Fox Experiment
Dmitry Konstantinovich Belyayev (Russian: ะะผะธฬััะธะน ะะพะฝััะฐะฝัะธฬะฝะพะฒะธั ะะตะปัฬะตะฒ, 17 July 1917 โ 14 November 1985) was a Russian geneticist and academician who served as director of the Institute of Cytology and Genetics (IC&G) of the USSR Academy of Sciences, Novosibirsk, from 1959 to 1985. His decades-long effort to breed domesticated foxes was described by The New York Times as โarguably the most extraordinary breeding experiment ever conducted.โ A 2010 article in Scientific American stated that Belyayev โmay be the man most responsible for our understanding of the process by which wolves were domesticated into our canine companions.โ
Beginning in the 1950s, in order to uncover the genetic basis of the distinctive behavioral and physiological attributes of domesticated animals, Belyayev and his team spent decades breeding the wild silver fox (Vulpes vulpes) and selecting for reproduction only those individuals in each generation that showed the least fear of humans. After several generations of controlled breeding, a majority of the silver foxes no longer showed any fear of humans and often wagged their tails and licked their human caretakers to show affection. They also began to display spotted coats, floppy ears, curled tails, as well as other physical attributes often found in domesticated animals, thus confirming Belyayevโs hypothesis that both the behavioral and physical traits of domesticated animals could be traced to "a collection of genes that conferred a propensity to tamenessโa genotype that the foxes perhaps shared with any species that could be domesticated".
Belyayevโs experiments were the result of a politically motivated demotion, in response to defying the now discredited non-Mendellian theories of Lysenkoism, which were politically accepted in the Soviet Union at the time. Belyayev has since been vindicated in recent years by major scientific journals, and by the Soviet establishment as a pioneering figure in modern genetics.
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- "Belyayev's Fox Experiment" | 2020-01-25 | 109 Upvotes 30 Comments