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🔗 Color

Impossible colors (forbidden, non-physical, unrealizable or chimerical colors) are supposed colors that do not appear in ordinary visual functioning. Non-physical colors are those notionally resulting from combinations of retinal outputs which cannot arise in normal vision. Chimerical colors are perceived, typically transiently, through contrast effects.

🔗 United States/U.S. Government 🔗 United States 🔗 Human rights 🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Medicine 🔗 Skepticism 🔗 Politics 🔗 Psychology 🔗 Military history/Intelligence 🔗 Alternative Views 🔗 Military history/Cold War 🔗 Politics/American politics 🔗 U.S. Congress 🔗 Psychoactive and Recreational Drugs 🔗 Drug Policy 🔗 United States/U.S. history 🔗 Science Policy

Project MKUltra was an illegal human experiments program designed and undertaken by the U.S. Central Intelligence Agency (CIA) to develop procedures and identify drugs that could be used during interrogations to weaken people and force confessions through brainwashing and psychological torture. It began in 1953 and was halted in 1973. MKUltra used numerous methods to manipulate its subjects' mental states and brain functions, such as the covert administration of high doses of psychoactive drugs (especially LSD) and other chemicals without the subjects' consent, electroshocks, hypnosis, sensory deprivation, isolation, verbal and sexual abuse, and other forms of torture.

MKUltra was preceded by Project Artichoke. It was organized through the CIA's Office of Scientific Intelligence and coordinated with the United States Army Biological Warfare Laboratories. The program engaged in illegal activities, including the use of U.S. and Canadian citizens as unwitting test subjects.^: 74 MKUltra's scope was broad, with activities carried out under the guise of research at more than 80 institutions aside from the military, including colleges and universities, hospitals, prisons, and pharmaceutical companies. The CIA operated using front organizations, although some top officials at these institutions were aware of the CIA's involvement.

MKUltra was revealed to the public in 1975 by the Church Committee of the United States Congress and Gerald Ford's United States President's Commission on CIA activities within the United States (the Rockefeller Commission). Investigative efforts were hampered by CIA Director Richard Helms's order that all MKUltra files be destroyed in 1973; the Church Committee and Rockefeller Commission investigations relied on the sworn testimony of direct participants and on the small number of documents that survived Helms's order. In 1977, a Freedom of Information Act request uncovered a cache of 20,000 documents relating to MKUltra, which led to Senate hearings. Some surviving information about MKUltra was declassified in 2001.

🔗 Mathematics

The Trachtenberg system is a system of rapid mental calculation. The system consists of a number of readily memorized operations that allow one to perform arithmetic computations very quickly. It was developed by the Russian Jewish engineer Jakow Trachtenberg in order to keep his mind occupied while being in a Nazi concentration camp.

The rest of this article presents some methods devised by Trachtenberg. Some of the algorithms Trachtenberg developed are ones for general multiplication, division and addition. Also, the Trachtenberg system includes some specialised methods for multiplying small numbers between 5 and 13.

The section on addition demonstrates an effective method of checking calculations that can also be applied to multiplication.

🔗 Physics 🔗 Astronomy

Entropic gravity, also known as emergent gravity, is a theory in modern physics that describes gravity as an entropic force—a force with macro-scale homogeneity but which is subject to quantum-level disorder—and 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 weak—levels seen only at interstellar distances—it 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 1.2×10⁻¹⁰ 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 12 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.

🔗 Mass surveillance 🔗 History 🔗 United Kingdom

The modern capabilities and legal framework for mass surveillance in the United Kingdom developed under successive governments of the United Kingdom since the late 20th century.

🔗 United States 🔗 United States/North Carolina 🔗 Appalachia 🔗 Tennessee

In the Appalachian Mountains of the eastern United States, balds are mountain summits or crests covered primarily by thick vegetation of native grasses or shrubs occurring in areas where heavy forest growth would be expected.

Balds are found primarily in the Southern Appalachians, where, even at the highest elevations, the climate is too warm to support an alpine zone, areas where trees fail to grow due to short or non-existent growing seasons. The difference between an alpine summit, such as Mount Washington in New Hampshire, and a bald, such as Gregory Bald in the Great Smoky Mountains, is that a lack of trees is normal for the colder climate of the former but abnormal for the warmer climate of the latter. One example of southern balds' abnormality can be found at Roan Mountain, where Roan High Knob (el. 6,285 ft/1,915 m) is coated with a dense stand of spruce-fir forest, whereas an adjacent summit, Round Bald (el. 5,826 ft/1,776 m), is almost entirely devoid of trees. Why some summits are bald and some are not is a mystery, though there are several hypotheses.

🔗 Russia 🔗 Physics 🔗 Physics/relativity 🔗 Russia/science and education in Russia

The Novikov self-consistency principle, also known as the Novikov self-consistency conjecture and Larry Niven's law of conservation of history, is a principle developed by Russian physicist Igor Dmitriyevich Novikov in the mid-1980s. Novikov intended it to solve the problem of paradoxes in time travel, which is theoretically permitted in certain solutions of general relativity that contain what are known as closed timelike curves. The principle asserts that if an event exists that would cause a paradox or any "change" to the past whatsoever, then the probability of that event is zero. It would thus be impossible to create time paradoxes.

🔗 Books

The Autumn of the Middle Ages, The Waning of the Middle Ages, or Autumntide of the Middle Ages (published in 1919 as Herfsttij der Middeleeuwen and translated into English in 1924, German in 1924, and French in 1932), is the best-known work by the Dutch historian Johan Huizinga.

In the book, Huizinga presents the idea that the exaggerated formality and romanticism of late medieval court society was a defense mechanism against the constantly increasing violence and brutality of general society. He saw the period as one of pessimism, cultural exhaustion, and nostalgia, rather than of rebirth and optimism.

His main conclusion is that the combination of required modernization of statehood governance, stuck in traditionalism, in combination with the exhausting inclusion of an ever-growing corpus of Catholic rites and popular beliefs in daily life, led to the implosion of late medieval society. This provided light to the rise of (religious) individualism, humanism and scientific progress: the renaissance.

The book was nominated for the 1939 Nobel Prize for Literature, but lost to the Finnish writer Frans Eemil Sillanpää.

Huizinga's work later came under some criticism, especially for relying too heavily on evidence from the rather exceptional case of the Burgundian court. Other criticisms include the writing of the book being "old-fashioned" and "too literary".

A new English translation of the book was published in 1996 because of perceived deficiencies in the original translation. The new translation, by Rodney Payton and Ulrich Mammitzsch, was based on the second edition of the Dutch publication in 1921 and compared with the German translation published in 1924.

To mark the centenary of Herfsttij, a new translation by Diane Webb appeared in 2020, published by Leiden University Press: Autumntide of the Middle Ages. According to Benjamin Kaplan, this translation "captures Huizinga's original voice better than either of the two previous English editions". This new English edition also includes for the first time 300 full-colour illustrations of all the works of art Huizinga mentions in his text.

In the 1970s, Radio Netherlands produced an audio series about the book, entitled "Autumn of the Middle Ages: A Six-part History in Words and Music from the Low Countries".

🔗 Finance & Investment 🔗 Economics 🔗 Business 🔗 Psychology

The Volfefe Index is a stock market index of volatility in market sentiment for US Treasury bonds caused by tweets by President Donald Trump.

Bloomberg News observed Volfefe was created due to the statistical significance of Trump tweets on bond prices. ABC News Online posited Volfefe could help analyze interest rate risk in the face of "unpredictable" activity on social media by Trump.

🔗 Astronomy 🔗 Astronomy/Astronomical objects

Hoag's Object is a non-typical galaxy of the type known as a ring galaxy. The galaxy is named after Arthur Hoag who discovered it in 1950 and identified it as either a planetary nebula or a peculiar galaxy with eight billion stars, spanning roughly 100,000 light years.