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🔗 Economics 🔗 European history

The Price Revolution, sometimes known as the Spanish Price Revolution, was a series of economic events that occurred between the second half of the 15th century and the first half of the 17th century, and most specifically linked to the high rate of inflation that occurred during this period across Western Europe. Prices rose on average roughly sixfold over 150 years. This level of inflation amounts to 1–1.5% per year, a relatively low inflation rate for modern-day standards, but rather high given the monetary policy in place in the 16th century.

Generally it is thought that this high inflation was caused by the large influx of gold and silver from the Spanish treasure fleet from the New World, including Mexico, Peru, and the rest of the Spanish Empire.

Specie flowed through Spain, increasing Spanish prices, and then spread over Western Europe as a result of Spanish balance of payments deficit. This enlarged the monetary supply and price levels of many European countries. Combined with this influx of gold and silver, population growth and urbanization perpetuated the price revolution. According to this theory, too many people with too much money chased too few goods.

🔗 Soviet Union 🔗 Russia 🔗 Russia/technology and engineering in Russia 🔗 Spaceflight 🔗 Russia/science and education in Russia 🔗 Russia/history of Russia

Sputnik 1 ( or ; "Satellite-1", or "PS-1", Простейший Спутник-1 or Prosteyshiy Sputnik-1, "Elementary Satellite 1") was the first artificial Earth satellite. The Soviet Union launched it into an elliptical low Earth orbit on 4 October 1957, orbiting for three weeks before its batteries died, then silently for two more months before falling back into the atmosphere. It was a 58 cm (23 in) diameter polished metal sphere, with four external radio antennas to broadcast radio pulses. Its radio signal was easily detectable by radio amateurs, and the 65° inclination and duration of its orbit made its flight path cover virtually the entire inhabited Earth. The satellite's unanticipated success precipitated the American Sputnik crisis and triggered the Space Race, a part of the Cold War. The launch was the beginning of a new era of political, military, technological, and scientific developments. The name "Sputnik" is Russian for spouse/traveling companion or satellite when interpreted in an astronomical context.

Tracking and studying Sputnik 1 from Earth provided scientists with valuable information. The density of the upper atmosphere could be deduced from its drag on the orbit, and the propagation of its radio signals gave data about the ionosphere.

Sputnik 1 was launched during the International Geophysical Year from Site No.1/5, at the 5th Tyuratam range, in Kazakh SSR (now known as the Baikonur Cosmodrome). The satellite travelled at about 29,000 kilometres per hour (18,000 mph; 8,100 m/s), taking 96.2 minutes to complete each orbit. It transmitted on 20.005 and 40.002 MHz, which were monitored by radio operators throughout the world. The signals continued for 21 days until the transmitter batteries ran out on 26 October 1957. Sputnik burned up on 4 January 1958 while reentering Earth's atmosphere, after three months, 1440 completed orbits of the Earth, and a distance travelled of about 70 million km (43 million mi).

🔗 Death 🔗 Italy 🔗 Hungary 🔗 Austria 🔗 Netherlands 🔗 Jewish history

A Stolperstein (pronounced [ˈʃtɔlpɐˌʃtaɪn] (listen); plural Stolpersteine; literally "stumbling stone", metaphorically a "stumbling block") is a sett-size, ten-centimetre (3.9 in) concrete cube bearing a brass plate inscribed with the name and life dates of victims of Nazi extermination or persecution.

The Stolpersteine project, initiated by the German artist Gunter Demnig in 1992, aims to commemorate individuals at exactly the last place of residency—or, sometimes, work—which was freely chosen by the person before he or she fell victim to Nazi terror, euthanasia, eugenics, deportation to a concentration or extermination camp, or escaped persecution by emigration or suicide. As of December 2019, 75,000 Stolpersteine have been laid, making the Stolpersteine project the world's largest decentralized memorial.

The majority of Stolpersteine commemorate Jewish victims of the Holocaust. Others have been placed for Sinti and Romani people (then also called "gypsies"), homosexuals, the physically or mentally disabled, Jehovah's Witnesses, black people, members of the Communist Party, the Social Democratic Party, and the anti-Nazi Resistance, the Christian opposition (both Protestants and Catholics), and Freemasons, along with International Brigade soldiers in the Spanish Civil War, military deserters, conscientious objectors, escape helpers, capitulators, "habitual criminals", looters, and others charged with treason, military disobedience, or undermining the Nazi military, as well as Allied soldiers.

🔗 Palaeontology

The cat gap is a period in the fossil record of approximately 25 to 18.5 million years ago in which there are few fossils of cats or cat-like species found in North America. The cause of the "cat gap" is disputed, but may have been caused by changes in the climate (global cooling), changes in the habitat and environmental ecosystem, the increasingly hypercarnivorous trend of the cats (especially the nimravids), volcanic activity, evolutionary changes in dental morphology of the Canidae species present in North America, or a periodicity of extinctions called van der Hammen cycles.

🔗 International relations 🔗 Mass surveillance 🔗 Internet 🔗 History 🔗 Computing 🔗 Internet culture 🔗 Economics 🔗 Law 🔗 Business 🔗 Politics 🔗 International relations/International law 🔗 Sociology 🔗 Futures studies 🔗 Capitalism 🔗 Globalization 🔗 Google

Surveillance capitalism has a number of meanings around the commodification of personal information. Since 2014, social psychologist Shoshana Zuboff has used and popularized the term.

🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Books 🔗 Military history/Intelligence 🔗 Military history/Maritime warfare 🔗 Military history/Military historiography

Blind Man's Bluff: The Untold Story of American Submarine Espionage (ISBN 0-06-103004-X) by Sherry Sontag, Christopher Drew, and Annette Lawrence Drew, published in 1998 by PublicAffairs, is a non-fiction book about U.S. Navy submarine operations during the Cold War. Several operations are described in the book, such as the use of USS Parche to tap Soviet undersea communications cables and USS Halibut to do the same in Operation Ivy Bells.

The book also contains an extensive list of collisions between Western and Soviet submarines and U.S. submarine awards.

🔗 Internet

Do Not Track (DNT) was a proposed HTTP header field, designed to allow internet users to opt-out of tracking by websites—which includes the collection of data regarding a user's activity across multiple distinct contexts, and the retention, use, or sharing of data derived from that activity outside the context in which it occurred.

The Do Not Track header was originally proposed in 2009 by researchers Christopher Soghoian, Sid Stamm, and Dan Kaminsky. Efforts to standardize Do Not Track by the W3C in the Tracking Preference Expression (DNT) Working Group did not make it past the Candidate Recommendation stage and ended in September 2018 due to insufficient deployment and support.Mozilla Firefox became the first browser to implement the feature, while Internet Explorer, Apple's Safari, Opera and Google Chrome all later added support.

DNT is not widely adopted by the industry, with companies citing the lack of legal mandates for its use, as well as unclear standards and guidelines for how websites are to interpret the header. Thus, it is not guaranteed that enabling DNT will actually have any effect at all. The W3C disbanded its DNT working group in January 2019, citing insufficient support and adoption. Apple discontinued support for DNT the following month.

🔗 Death 🔗 Visual arts 🔗 Latin

Memento mori (Latin for 'remember that you [have to] die') is an artistic or symbolic trope acting as a reminder of the inevitability of death. The concept has its roots in the philosophers of classical antiquity and Christianity, and appeared in funerary art and architecture from the medieval period onwards.

The most common motif is a skull, often accompanied by one or more bones. Often this alone is enough to evoke the trope, but other motifs such as a coffin, hourglass and wilting flowers signified the impermanence of human life. Often these function within a work whose main subject is something else, such as a portrait, but the vanitas is an artistic genre where the theme of death is the main subject. The Danse Macabre and Death personified with a scythe as the Grim Reaper are even more direct evocations of the trope.

🔗 Robotics

An eigenface () is the name given to a set of eigenvectors when used in the computer vision problem of human face recognition. The approach of using eigenfaces for recognition was developed by Sirovich and Kirby (1987) and used by Matthew Turk and Alex Pentland in face classification. The eigenvectors are derived from the covariance matrix of the probability distribution over the high-dimensional vector space of face images. The eigenfaces themselves form a basis set of all images used to construct the covariance matrix. This produces dimension reduction by allowing the smaller set of basis images to represent the original training images. Classification can be achieved by comparing how faces are represented by the basis set.

🔗 Technology 🔗 Spaceflight 🔗 Solar System/Mars 🔗 Solar System

Terraforming of Mars is a procedure that would comprise of planetary engineering project or concurrent projects, with the goal of transforming the planet from one hostile to terrestrial life to one that can sustainably host humans and other lifeforms free of protection or mediation. The process would presumably involve the rehabilitation of the planet's extant climate, atmosphere, and surface through a variety of resource-intensive initiatives, and the installation of a novel ecological system or systems.

Justifications for choosing Mars over other potential terraforming targets include the presence of water and a geological history that suggests it once harbored a dense atmosphere similar to Earth’s. Hazards and difficulties include low gravity, low light levels relative to Earth’s, and the lack of a magnetic field.

Objections to the project include questions about its feasibility, general ethical concerns about terraforming, and the considerable cost that such an undertaking would involve. Reasons for terraforming the planet include allaying concerns about resource use and depletion on Earth and arguments that the altering and subsequent or concurrent settlement of other planets decreases the odds of humanity's extinction.

Disagreement exists about whether current technology could render the planet habitable.