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🔗 Gilbert U-238 Atomic Energy Laboratory

🔗 Education 🔗 Toys

The Gilbert U-238 Atomic Energy Lab is a toy lab set that was produced by Alfred Carlton Gilbert, who was an American athlete, magician, toy-maker, business man, and inventor of the well-known Erector Set. The Atomic Energy Lab was released by the A. C. Gilbert Company in 1950. The kit's intention was to allow children to create and watch nuclear and chemical reactions using radioactive material.

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🔗 Claude Shannon

🔗 United States 🔗 Biography 🔗 Computer science 🔗 Telecommunications 🔗 Systems 🔗 Biography/science and academia 🔗 Cryptography 🔗 Cryptography/Computer science 🔗 Electronics 🔗 Systems/Systems theory 🔗 Telecommunications/Bell System 🔗 Cycling

Claude Elwood Shannon (April 30, 1916 – February 24, 2001) was an American mathematician, electrical engineer, and cryptographer known as "the father of information theory". Shannon is noted for having founded information theory with a landmark paper, "A Mathematical Theory of Communication", that he published in 1948.

He is also well known for founding digital circuit design theory in 1937, when—as a 21-year-old master's degree student at the Massachusetts Institute of Technology (MIT)—he wrote his thesis demonstrating that electrical applications of Boolean algebra could construct any logical numerical relationship. Shannon contributed to the field of cryptanalysis for national defense during World War II, including his fundamental work on codebreaking and secure telecommunications.

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🔗 Nicolas Bourbaki: The Greatest Mathematician That Never Existed

🔗 Mathematics 🔗 France

Nicolas Bourbaki (French pronunciation: ​[nikɔla buʁbaki]) is the collective pseudonym of a group of mathematicians, predominantly French alumni of the École normale supérieure (ENS). Founded in 1934–1935, the Bourbaki group originally intended to prepare a new textbook in analysis. Over time the project became much more ambitious, growing into a large series of textbooks published under the Bourbaki name, meant to treat modern pure mathematics. The series is known collectively as the Éléments de mathématique (Elements of Mathematics), the group's central work. Topics treated in the series include set theory, abstract algebra, topology, analysis, Lie groups and Lie algebras.

Bourbaki was founded in response to the effects of the First World War which caused the death of a generation of French mathematicians; as a result, young university instructors were forced to use dated texts. While teaching at the University of Strasbourg, Henri Cartan complained to his colleague André Weil of the inadequacy of available course material, which prompted Weil to propose a meeting with others in Paris to collectively write a modern analysis textbook. The group's core founders were Cartan, Claude Chevalley, Jean Delsarte, Jean Dieudonné and Weil; others participated briefly during the group's early years, and membership has changed gradually over time. Although former members openly discuss their past involvement with the group, Bourbaki has a custom of keeping its current membership secret.

The group's namesake derives from the 19th century French general Charles-Denis Bourbaki, who had a career of successful military campaigns before suffering a dramatic loss in the Franco-Prussian War. The name was therefore familiar to early 20th century French students. Weil remembered an ENS student prank in which an upperclassman posed as a professor and presented a "theorem of Bourbaki"; the name was later adopted.

The Bourbaki group holds regular private conferences for the purpose of drafting and expanding the Éléments. Topics are assigned to subcommittees, drafts are debated, and unanimous agreement is required before a text is deemed fit for publication. Although slow and labor-intensive, the process results in a work which meets the group's standards for rigour and generality. The group is also associated with the Séminaire Bourbaki, a regular series of lectures presented by members and non-members of the group, also published and disseminated as written documents. Bourbaki maintains an office at the ENS.

Nicolas Bourbaki was influential in 20th century mathematics, particularly during the middle of the century when volumes of the Éléments appeared frequently. The group is noted among mathematicians for its rigorous presentation and for introducing the notion of a mathematical structure, an idea related to the broader, interdisciplinary concept of structuralism. Bourbaki's work informed the New Math, a trend in elementary math education during the 1960s. Although the group remains active, its influence is considered to have declined due to infrequent publication of new volumes of the Éléments. However the collective's most recent publication appeared in 2016, treating algebraic topology.

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🔗 The Machine Stops

🔗 Novels 🔗 Radio 🔗 Novels/Science fiction 🔗 Novels/Short story

"The Machine Stops" is a science fiction short story (12,300 words) by E. M. Forster. After initial publication in The Oxford and Cambridge Review (November 1909), the story was republished in Forster's The Eternal Moment and Other Stories in 1928. After being voted one of the best novellas up to 1965, it was included that same year in the populist anthology Modern Short Stories. In 1973 it was also included in The Science Fiction Hall of Fame, Volume Two.

The story, set in a world where humanity lives underground and relies on a giant machine to provide its needs, predicted technologies similar to instant messaging and the Internet.

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🔗 Nutraloaf

🔗 United States 🔗 Food and drink 🔗 Correction and Detention Facilities

Nutraloaf (also known as Meal Loaf, prison loaf, disciplinary loaf, food loaf, lockup loaf, confinement loaf, seg loaf, grue or special management meal) is a food served in prisons in the United States and formerly Canada to inmates who have misbehaved; for example, assaulting prison guards or fellow prisoners. It is similar to meatloaf in texture, but has a wider variety of ingredients. Prison loaf is usually bland, perhaps even unpleasant, but prison wardens argue that nutraloaf provides enough nutrition to keep prisoners healthy without requiring utensils to be issued.

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🔗 Mycorrhizal Network

🔗 Fungi 🔗 Plants

A mycorrhizal network (also known as a common mycorrhizal network or CMN) is an underground network found in forests and other plant communities, created by the hyphae of mycorrhizal fungi joining with plant roots. This network connects individual plants together. Mycorrhizal relationships are most commonly mutualistic, with both partners benefiting, but can be commensal or parasitic, and a single partnership may change between any of the three types of symbiosis at different times. Mycorrhizal networks were discovered in 1997 by Suzanne Simard, professor of forest ecology at the University of British Columbia in Canada. Simard grew up in Canadian forests where her family had made a living as foresters for generations. Her field studies revealed that trees are linked to neighboring trees by an underground network of fungi that resembles the neural networks in the brain. In one study, Simard watched as a Douglas fir that had been injured by insects appeared to send chemical warning signals to a ponderosa pine growing nearby. The pine tree then produced defense enzymes to protect against the insect.

The formation and nature of these networks is context-dependent, and can be influenced by factors such as soil fertility, resource availability, host or mycosymbiont genotype, disturbance and seasonal variation. Some plant species, such as buckhorn plantain, a common lawn and agricultural weed, benefit from mycorrhizal relationships in conditions of low soil fertility, but are harmed in higher soil fertility. Both plants and fungi associate with multiple symbiotic partners at once, and both plants and fungi are capable of preferentially allocating resources to one partner over another.

Mycorrhizal associations have profoundly impacted the evolution of plant life on Earth ever since the initial adaptation of plant life to land. In evolutionary biology, mycorrhizal symbiosis has prompted inquiries into the possibility that symbiosis, not competition, is the main driver of evolution.

Referencing an analogous function served by the World Wide Web in human communities, the many roles that mycorrhizal networks appear to play in woodland have earned them a colloquial nickname: the "Wood Wide Web". Many of the claims made about common mycorrhizal networks, including that they are ubiquitous in forests, that resources are transferred between plants through them, and that they are used to transfer warnings between trees, have been criticised as being not strongly supported by evidence.

🔗 Atari Video Music

🔗 Video games 🔗 Visual arts

The Atari Video Music (Model C240) is the earliest commercial electronic music visualizer released. It was manufactured by Atari, Inc., and released in 1977 for $169.95. The system creates an animated visual display that responds to musical input from a Hi-Fi stereo system for the visual entertainment of consumers.

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🔗 The Einstein–Szilárd Letter

🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Military history/Military science, technology, and theory 🔗 Physics 🔗 Military history/World War II 🔗 Physics/History

The Einstein–Szilárd letter was a letter written by Leó Szilárd and signed by Albert Einstein that was sent to the United States President Franklin D. Roosevelt on August 2, 1939. Written by Szilárd in consultation with fellow Hungarian physicists Edward Teller and Eugene Wigner, the letter warned that Germany might develop atomic bombs and suggested that the United States should start its own nuclear program. It prompted action by Roosevelt, which eventually resulted in the Manhattan Project developing the first atomic bombs.

🔗 Nothing-up-my-sleeve number

🔗 Cryptography 🔗 Cryptography/Computer science

In cryptography, nothing-up-my-sleeve numbers are any numbers which, by their construction, are above suspicion of hidden properties. They are used in creating cryptographic functions such as hashes and ciphers. These algorithms often need randomized constants for mixing or initialization purposes. The cryptographer may wish to pick these values in a way that demonstrates the constants were not selected for a nefarious purpose, for example, to create a backdoor to the algorithm. These fears can be allayed by using numbers created in a way that leaves little room for adjustment. An example would be the use of initial digits from the number π as the constants. Using digits of π millions of places after the decimal point would not be considered trustworthy because the algorithm designer might have selected that starting point because it created a secret weakness the designer could later exploit—though even with natural-seeming selections, enough entropy exists in the possible choices that the utility of these numbers has been questioned.

Digits in the positional representations of real numbers such as π, e, and irrational roots are believed to appear with equal frequency (see normal number). Such numbers can be viewed as the opposite extreme of Chaitin–Kolmogorov random numbers in that they appear random but have very low information entropy. Their use is motivated by early controversy over the U.S. Government's 1975 Data Encryption Standard, which came under criticism because no explanation was supplied for the constants used in its S-box (though they were later found to have been carefully selected to protect against the then-classified technique of differential cryptanalysis). Thus a need was felt for a more transparent way to generate constants used in cryptography.

"Nothing up my sleeve" is a phrase associated with magicians, who sometimes preface a magic trick by holding open their sleeves to show they have no objects hidden inside.

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🔗 The If-by-whiskey fallacy

🔗 Philosophy 🔗 Philosophy/Logic

In political discourse, if-by-whiskey is a relativist fallacy in which the speaker's position is contingent on the listener's opinion. An if-by-whiskey argument implemented through doublespeak appears to affirm both sides of an issue, and agrees with whichever side the listener supports, in effect taking a position without taking a position. The statement typically uses words with strongly positive or negative connotations (e.g., terrorist as negative and freedom fighter as positive).

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