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🔗 Architecture

Star lifting is any of several hypothetical processes by which a sufficiently advanced civilization (specifically, one of Kardashev-II or higher) could remove a substantial portion of a star's matter which can then be re-purposed, while possibly optimizing the star's energy output and lifespan at the same time. The term appears to have been coined by David Criswell.

Stars already lose a small flow of mass via solar wind, coronal mass ejections, and other natural processes. Over the course of a star's life on the main sequence this loss is usually negligible compared to the star's total mass; only at the end of a star's life when it becomes a red giant or a supernova is a large proportion of material ejected. The star lifting techniques that have been proposed would operate by increasing this natural plasma flow and manipulating it with magnetic fields.

Stars have deep gravity wells, so the energy required for such operations is large. For example, lifting solar material from the surface of the Sun to infinity requires 2.1 × 10¹¹ J/kg. This energy could be supplied by the star itself, collected by a Dyson sphere; using 10% of the Sun's total power output would allow 5.9 × 10²¹ kilograms of matter to be lifted per year (0.0000003% of the Sun's total mass), or 8% of the mass of Earth's moon.

🔗 Film 🔗 Film/Filmmaking

Soundies are three-minute American musical films, produced between 1940 and 1947, each displaying a song, dance, and/or band or orchestral number. Produced professionally on 35 mm black-and-white film, like theatrical motion pictures, they were printed on the more portable and economical 16 mm film.

The films were shown in a coin-operated "movie jukebox" named the Panoram, manufactured by the Mills Novelty Company of Chicago. Each Panoram housed a 16 mm RCA film projector, with eight Soundies films threaded in an endless-loop arrangement. A system of mirrors flashed the image from the lower half of the cabinet onto a front-facing screen in the top half. Each film cost 10 cents to play, with no choice of song; the patron saw whatever film was next in the queue. Panorams could be found in public amusement centers, nightclubs, taverns, restaurants, and factory lounges, and the films were changed weekly. The completed Soundies were generally made available within a few weeks of their filming, by the Soundies Distributing Corporation of America.

Several production companies filmed the Soundies shorts in New York City, Hollywood, and Chicago: James Roosevelt's Globe Productions (1940–41), Cinemasters (1940–41), Minoco Productions (owned by Mills Novelty, 1941–43), RCM Productions (1941–46), LOL Productions (1943), Glamourettes (1943), Filmcraft Productions (1943–46), and Alexander Productions (1946) led by William D. Alexander). The performers recorded the music in advance, and mimed to the soundtrack during filming.

The movie-jukebox idea developed several imitations and variations of the technical design; the most successful of these imitators were the Techniprocess company (managed by Rudy Vallee) and the Featurettes company, which used original novelty songs and usually unknown talent (17-year-old Gwen Verdon appears in a couple of the Featurettes as "Gwen Verdun"). As Soundies quickly gained most of the market for jukebox films, the other companies disbanded, and some sold their films to the Soundies concern.

🔗 Meteorology 🔗 Paranormal

New England's Dark Day occurred on May 19, 1780, when an unusual darkening of the day sky was observed over the New England states and parts of Canada. The primary cause of the event is believed to have been a combination of smoke from forest fires, a thick fog, and cloud cover. The darkness was so complete that candles were required from noon on. It did not disperse until the middle of the next night.

🔗 Visual arts 🔗 Morocco

Zellige (Arabic: [zˈliʑ]; Arabic: الزليج‎; also zelige or zellij or zileej) is mosaic tilework made from individually chiseled geometric tiles set into a plaster base. This form of Islamic art is one of the main characteristics of Moroccan architecture. It consists of geometrically patterned mosaics, used to ornament walls, ceilings, fountains, floors, pools and tables. The Moroccan traditional patterns and styles are found inside famous buildings such as Al-Qarawiyyin Mosque in Fez, the Alhambra in Granada, Spain, the Great Mosque of Cordoba, the Ben Youssef Madrasa in Marrakech, and the Hassan II mosque in Casablanca, which adds a new color palette with traditional designs.

🔗 Computing 🔗 Computing/Software 🔗 Computing/Computer science 🔗 Cryptography 🔗 Cryptography/Computer science 🔗 Computing/Computer Security

Post-quantum cryptography (sometimes referred to as quantum-proof, quantum-safe or quantum-resistant) refers to cryptographic algorithms (usually public-key algorithms) that are thought to be secure against an attack by a quantum computer. As of 2019, this is not true for the most popular public-key algorithms, which can be efficiently broken by a sufficiently strong quantum computer. The problem with currently popular algorithms is that their security relies on one of three hard mathematical problems: the integer factorization problem, the discrete logarithm problem or the elliptic-curve discrete logarithm problem. All of these problems can be easily solved on a sufficiently powerful quantum computer running Shor's algorithm. Even though current, publicly known, experimental quantum computers lack processing power to break any real cryptographic algorithm, many cryptographers are designing new algorithms to prepare for a time when quantum computing becomes a threat. This work has gained greater attention from academics and industry through the PQCrypto conference series since 2006 and more recently by several workshops on Quantum Safe Cryptography hosted by the European Telecommunications Standards Institute (ETSI) and the Institute for Quantum Computing.

In contrast to the threat quantum computing poses to current public-key algorithms, most current symmetric cryptographic algorithms and hash functions are considered to be relatively secure against attacks by quantum computers. While the quantum Grover's algorithm does speed up attacks against symmetric ciphers, doubling the key size can effectively block these attacks. Thus post-quantum symmetric cryptography does not need to differ significantly from current symmetric cryptography. See section on symmetric-key approach below.

🔗 Iran 🔗 Alternative Views 🔗 Iraq

The Baghdad Battery or Parthian Battery is a set of three artifacts which were found together: a ceramic pot, a tube of copper, and a rod of iron. It was discovered in modern Khujut Rabu, Iraq, close to the metropolis of Ctesiphon, the capital of the Parthian (150 BC – 223 AD) and Sasanian (224–650 AD) empires of Persia, and it is considered to date from either of these periods.

Its origin and purpose remain unclear. It was hypothesized by some researchers that the object functioned as a galvanic cell, possibly used for electroplating, or some kind of electrotherapy, but there is no electroplated object known from this period. An alternative explanation is that it functioned as a storage vessel for sacred scrolls.

🔗 Technology 🔗 Electronics 🔗 Engineering 🔗 Industrial design

Muntzing is the practice and technique of reducing the components inside an electronic appliance to the minimum required for it to sufficiently function in most operating conditions, reducing design margins above minimum requirements toward zero. The term is named after the man who invented it, Earl "Madman" Muntz, a car and electronics salesman, who was not formally educated or trained in any science or engineering discipline.

In the 1940s and 1950s, television receivers were relatively new to the consumer market, and were more complex pieces of equipment than the radios which were then in popular use. TVs often contained upwards of 30 vacuum tubes, as well as transformers, rheostats, and other electronics. The consequence of high cost was high sales pricing, limiting potential for high-volume sales. Muntz expressed suspicion of complexity in circuit designs, and determined through simple trial and error that he could remove a significant number of electronic components from a circuit design and still end up with a monochrome TV that worked sufficiently well in urban areas, close to transmission towers where the broadcast signal was strong. He carried a pair of wire clippers, and when he felt that one of his builders was overengineering a circuit, he would begin snipping out some of the electronics components. When the TV stopped functioning, he would have the technician reinsert the last removed part. He would repeat the snipping in other portions of the circuit until he was satisfied in his simplification efforts, and then leave the TV as it was without further testing in more adverse conditions for signal reception.

As a result, he reduced his costs and increased his profits at the expense of poorer performance at locations more distant from urban centers. He reasoned that population density was higher in and near the urban centers where the TVs would work, and lower further out where the TVs would not work, so the Muntz TVs were adequate for a very large fraction of his customers. And for those further out, where the Muntz TVs did not work, those could be returned at the customer's additional effort and expense, and not Muntz's. He focused less resources in the product, intentionally accepting bare minimum performance quality, and focused more resources on advertising and sales promotions.

🔗 Computing 🔗 Computing/Computer hardware

Millipede memory is a form of non-volatile computer memory. It promised a data density of more than 1 terabit per square inch (1 gigabit per square millimeter), which is about the limit of the perpendicular recording hard drives. Millipede storage technology was pursued as a potential replacement for magnetic recording in hard drives and a means of reducing the physical size of the technology to that of flash media.

IBM demonstrated a prototype millipede storage device at CeBIT 2005, and was trying to make the technology commercially available by the end of 2007. However, because of concurrent advances in competing storage technologies, no commercial product has been made available since then.

🔗 Death 🔗 Agriculture 🔗 China 🔗 Skepticism 🔗 Alternative medicine 🔗 Arab world 🔗 Agriculture/Beekeeping

A mellified man, or a human mummy confection, was a legendary medicinal substance created by steeping a human cadaver in honey. The concoction is detailed in Chinese medical sources, most significantly the Bencao Gangmu of the 16th-century Chinese medical doctor and pharmacologist Li Shizhen. Relying on a second-hand account, Li reports a story that some elderly men in Arabia, nearing the end of their lives, would submit themselves to a process of mummification in honey to create a healing confection.

This process differed from a simple body donation because of the aspect of self-sacrifice; the mellification process would ideally start before death. The donor would stop eating any food other than honey, going as far as to bathe in the substance. Shortly, his feces (and even his sweat, according to legend) would consist of honey. When this diet finally proved fatal, the donor's body would be placed in a stone coffin filled with honey.

After a century or so, the contents would have turned into a sort of confection reputedly capable of healing broken limbs and other ailments. This confection would then be sold in street markets as a hard to find item with a hefty price.

🔗 Finance & Investment 🔗 Economics 🔗 Food and drink 🔗 Food and drink/Foodservice 🔗 Retailing 🔗 Globalization

The Big Mac Index is a price index published by The Economist as an informal way of measuring the purchasing power parity (PPP) between two currencies and provides a test of the extent to which market exchange rates result in goods costing the same in different countries. It "seeks to make exchange-rate theory a bit more digestible."

The index, created in 1986, takes its name from the Big Mac, a hamburger sold at McDonald's restaurants.