Random Articles (Page 6)

Have a deep view into what people are curious about.

πŸ”— Secure Remote Password protocol

πŸ”— Computing πŸ”— Computing/Networking

The Secure Remote Password protocol (SRP) is an augmented password-authenticated key agreement (PAKE) protocol, specifically designed to work around existing patents.

Like all PAKE protocols, an eavesdropper or man in the middle cannot obtain enough information to be able to brute force guess a password without further interactions with the parties for each guess. Furthermore, being an augmented PAKE protocol, the server does not store password-equivalent data. This means that an attacker who steals the server data cannot masquerade as the client unless they first perform a brute force search for the password.

In layman's terms, during SRP (or any other PAKE protocol) authentication, one party (the "client" or "user") demonstrates to another party (the "server") that they know the password, without sending the password itself nor any other information from which the password can be derived. The password never leaves the client and is unknown to the server.

Furthermore, the server also needs to know about the password (but not the password itself) in order to instigate the secure connection. This means that the server also authenticates itself to the client, without reliance on the user parsing complex URLs. This prevents Phishing.

Discussed on

πŸ”— Albert Stevens

πŸ”— Biography

Albert Stevens (1887–1966), also known as patient CAL-1, was a victim of a human radiation experiment, and survived the highest known accumulated radiation dose in any human. On May 14, 1945, he was injected with 131 kBq (3.55 Β΅Ci) of plutonium without his knowledge or informed consent.

Plutonium remained present in his body for the remainder of his life, the amount decaying slowly through radioactive decay and biological elimination. Stevens died of heart disease some 20 years later, having accumulated an effective radiation dose of 64 Sv (6400 rem) over that period, i.e. an average of 3 Sv per year or 350Β ΞΌSv/h. The current annual permitted dose for a radiation worker in the United States is 0.05 Sv (or 5 rem), i.e. an average of 5.7 ΞΌSv/h.

Discussed on

πŸ”— The Population Bomb (1968)

πŸ”— Environment πŸ”— Books πŸ”— Futures studies πŸ”— Molecular Biology πŸ”— Molecular Biology/Genetics

The Population Bomb is a 1968 book co-authored by former Stanford University professor Paul R. Ehrlich and former Stanford senior researcher in conservation biology Anne H. Ehrlich. From the opening page, it predicted worldwide famines due to overpopulation, as well as other major societal upheavals, and advocated immediate action to limit population growth. Fears of a "population explosion" existed in the mid-20th century baby boom years, but the book and its authors brought the idea to an even wider audience.

The book has been criticized since its publication for an alarmist tone, and over the subsequent decades, for inaccurate assertions and failed predictions. For instance, regional famines have occurred since the publication of the book, but not world famines. The Ehrlichs themselves still stand by the book despite the flaws identified by its critics, with Paul stating in 2009 that "perhaps the most serious flaw in The Bomb was that it was much too optimistic about the future," despite having predicted catastrophic global famines that never came to pass. They believe that it achieved their goals because "it alerted people to the importance of environmental issues and brought human numbers into the debate on the human future."

πŸ”— Gompertz Function

πŸ”— Mathematics πŸ”— Statistics

The Gompertz curve or Gompertz function is a type of mathematical model for a time series, named after Benjamin Gompertz (1779–1865). It is a sigmoid function which describes growth as being slowest at the start and end of a given time period. The right-side or future value asymptote of the function is approached much more gradually by the curve than the left-side or lower valued asymptote. This is in contrast to the simple logistic function in which both asymptotes are approached by the curve symmetrically. It is a special case of the generalised logistic function. The function was originally designed to describe human mortality, but since has been modified to be applied in biology, with regard to detailing populations.

πŸ”— Ulugh Beg Observatory

πŸ”— Astronomy πŸ”— Central Asia πŸ”— Museums πŸ”— Central Asia/Uzbekistan

The Ulugh Beg Observatory is an observatory in Samarkand, Uzbekistan. Built in the 1420s by the Timurid astronomer Ulugh Beg. Islamic astronomers who worked at the observatory include Al-Kashi, Ali Qushji, and Ulugh Beg himself. The observatory was destroyed in 1449 and rediscovered in 1908.

Discussed on

πŸ”— Rapatronic Camera

πŸ”— Military history πŸ”— Military history/Military science, technology, and theory πŸ”— Military history/Weaponry πŸ”— Engineering πŸ”— Photography πŸ”— Photography/History of photography

The rapatronic camera (a portmanteau of rapid action electronic) is a high-speed camera capable of recording a still image with an exposure time as brief as 10 nanoseconds.

The camera was developed by Harold Edgerton in the 1940s and was first used to photograph the rapidly changing matter in nuclear explosions within milliseconds of detonation, using exposures of several microseconds. To overcome the speed limitation of a conventional camera's mechanical shutter, the rapatronic camera uses two polarizing filters and a Faraday cell (or in some variants a Kerr cell). The two filters are mounted with their polarization angles at 90Β° to each other, to block all incoming light. The Faraday cell sits between the filters and changes the polarization plane of light passing through it depending on the level of magnetic field applied, acting as a shutter when it is energized at the right time for a very short amount of time, allowing the film to be properly exposed.

In magneto-optical shutters, the active material of the Faraday cell (e.g. dense flint glass, which reacts well to a strong magnetic field) is located inside an electromagnet coil, formed by a few loops of thick wire. The coil is powered from a pulse forming network by discharging a high-voltage capacitor (e.g. 2 microfarads at 1000 volts), into the coil via a trigatron or a thyratron switch. In electro-optical shutters, the active material is a liquid, typically nitrobenzene, located in a cell between two electrodes. A brief impulse of high voltage is applied to rotate the polarization of the passing light.

For a film-like sequence of high-speed photographs, as used in the photography of nuclear and thermonuclear tests, arrays of up to 12 cameras were deployed, with each camera carefully timed to record sequentially. Each camera was capable of recording only one exposure on a single sheet of film. Therefore, in order to create time-lapse sequences, banks of four to ten cameras were set up to take photos in rapid succession. The average exposure time used was three microseconds.

Discussed on

πŸ”— Dril

πŸ”— Biography πŸ”— Internet culture πŸ”— Comedy πŸ”— Biography/arts and entertainment

@dril is a pseudonymous Twitter user best known for his idiosyncratic style of absurdist humor and non sequiturs. The account, its author, and the character associated with the tweets are all commonly referred to as dril (the handle without the at sign) or wint (the account's display name), both rendered lowercase but often capitalized by others. Since his first tweet in 2008, dril has become a popular and influential Twitter user with more than one million followers.

dril is one of the most notable accounts associated with "Weird Twitter", a subculture on the site that shares a surreal, ironic sense of humor. The character associated with dril is highly distinctive, often described as a bizarre reflection of a typical male American Internet user. Other social media users have repurposed dril's tweets for humorous or satiric effect in a variety of political and cultural contexts. Many of dril's tweets, phrases, and tropes have become familiar parts of Internet slang.

The author behind dril remained unknown for years, with the few available details about the author's life fueling speculation about his identity. In 2017, dril's author was "doxxed" (in other words, his identity was exposed) in a post that went viral and received media attention. After the doxxing, many Twitter users and journalists preferred to preserve dril's pseudonymity out of respect for the author's personal privacy and the character's mystique.

Beyond tweeting, dril has created animated short films and contributed illustrations and writing to other artists' collaborative projects. His first book, Dril Official "Mr. Ten Years" Anniversary Collection (2018), is a compilation of the account's "greatest hits" alongside new illustrations. In 2019 he announced the launch of a streaming web series called Truthpoint: Darkweb Rising, an InfoWars parody co-created with comedian Derek Estevez-Olsen for Adult Swim. Writers have praised dril for the originality and humor of his tweets; for example, the poet Patricia Lockwood called dril "a master of tone [and] character," and The A.V. Club dubbed him "arguably the most iconic Twitter account in the history of social media."

Discussed on

  • "Dril" | 2019-11-24 | 56 Upvotes 4 Comments

πŸ”— Matrioshka Brain

πŸ”— Technology πŸ”— Architecture

A Matrioshka brain is a hypothetical megastructure of immense computational capacity powered by a Dyson sphere. It was proposed in 1997 by Robert J. Bradbury (1956–2011). It is an example of a Class B stellar engine, employing the entire energy output of a star to drive computer systems. This concept derives its name from the nesting Russian Matryoshka dolls. The concept was deployed by Bradbury in the anthology Year Million: Science at the Far Edge of Knowledge.

Discussed on

πŸ”— Caproni Ca.60

πŸ”— Aviation πŸ”— Aviation/aircraft

The Caproni Ca.60 Transaereo, often referred to as the Noviplano (nine-wing) or Capronissimo, was the prototype of a large nine-wing flying boat intended to become a 100-passenger transatlantic airliner. It featured eight engines and three sets of triple wings.

Only one example of this aircraft, designed by Italian aviation pioneer Gianni Caproni, was built by the Caproni company. It was tested on Lake Maggiore in 1921: its brief maiden flight took place on February 12 or March 2. Its second flight was March 4; shortly after takeoff, the aircraft crashed on the water surface and broke up upon impact. The Ca.60 was further damaged when the wreck was towed to shore and, in spite of Caproni's intention to rebuild the aircraft, the project was soon abandoned because of its excessive cost. The few surviving parts are on display at the Gianni Caproni Museum of Aeronautics and at the Volandia aviation museum in Italy.

Discussed on

πŸ”— Nobel Disease

πŸ”— Skepticism πŸ”— Psychology πŸ”— Sociology πŸ”— Paranormal

Nobel disease or Nobelitis is the embracing of strange or scientifically unsound ideas by some Nobel Prize winners, usually later in life. It has been argued that the effect results, in part, from a tendency for Nobel winners to feel empowered by the award to speak on topics outside their specific area of expertise, although it is unknown whether Nobel Prize winners are more prone to this tendency than other individuals. Paul Nurse, co-winner of the 2001 Nobel Prize in Physiology or Medicine, warned later laureates against "believing you are expert in almost everything, and being prepared to express opinions about most issues with great confidence, sheltering behind the authority that the Nobel Prize can give you". Nobel disease has been described as a "tongue in cheek" term.

Discussed on