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πŸ”— Computus – The calculation to determine the day of Easter

πŸ”— Time πŸ”— Christianity

The computus (Latin for 'computation') is a calculation that determines the calendar date of Easter. Easter is traditionally celebrated on the first Sunday after the Paschal full moon, which is the first full moon on or after 21 March (an approximation of the March equinox). Determining this date in advance requires a correlation between the lunar months and the solar year, while also accounting for the month, date, and weekday of the calendar. The calculations produce different results depending on whether the Julian calendar or the Gregorian calendar is used.

In late antiquity, it was feasible for the entire Christian church to receive the date of Easter each year through an annual announcement from the Pope. By the early third century, however, communications had deteriorated to the point that the church put great value in a system that would allow the clergy to independently and consistently determine the date for themselves. Additionally, the church wished to eliminate dependencies on the Hebrew calendar, by deriving Easter directly from the vernal equinox.

In The Reckoning of Time (725), Bede uses computus as a general term for any sort of calculation, although he refers to the Easter cycles of Theophilus as a "Paschal computus." By the end of the 8th century, computus came to refer specifically to the calculation of time.

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πŸ”— Pi Calculus

πŸ”— Computing πŸ”— Computer science

In theoretical computer science, the Ο€-calculus (or pi-calculus) is a process calculus. The Ο€-calculus allows channel names to be communicated along the channels themselves, and in this way it is able to describe concurrent computations whose network configuration may change during the computation.

The Ο€-calculus is simple, it has few terms and so is a small, yet expressive language (see #Syntax). Functional programs can be encoded into the Ο€-calculus, and the encoding emphasises the dialogue nature of computation, drawing connections with game semantics. Extensions of the Ο€-calculus, such as the spi calculus and applied Ο€, have been successful in reasoning about cryptographic protocols. Beside the original use in describing concurrent systems, the Ο€-calculus has also been used to reason about business processes and molecular biology.

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πŸ”— Paradox of hedonism: Pursuing happiness leads to misery

πŸ”— Philosophy πŸ”— Philosophy/Logic πŸ”— Philosophy/Ethics

The paradox of hedonism, also called the pleasure paradox, refers to the practical difficulties encountered in the pursuit of pleasure. For the hedonist, constant pleasure-seeking may not yield the most actual pleasure or happiness in the long runβ€”or even in the short run, when consciously pursuing pleasure interferes with experiencing it.

The utilitarian philosopher Henry Sidgwick was first to note in The Methods of Ethics that the paradox of hedonism is that pleasure cannot be acquired directly. Variations on this theme appear in the realms of ethics, philosophy, psychology, and economics.

πŸ”— Interactive EasyFlow

Interactive EasyFlow was one of the first diagramming and flow charting software packages available for personal computers. This product was the flagship software produced by HavenTree Software Limited, of Kingston, Ontario Canada. HavenTree software, formed in 1981, offered predecessor non-interactive products "EasyFlow" (1983) and "EasyFlow-Plus" (1984). Interactive EasyFlow - so named to distinguish it from the preceding products - was offered from 1985 until the early 1990s, when the company dropped the "Interactive" adjective in favour of simply "HavenTree EasyFlow". It offered the software for sale until it filed for protection under Canada's Bankruptcy and Insolvency Act in April 1996. The assets of the company were purchased by SPSS Inc. in 1998.

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πŸ”— Cassowary

πŸ”— Australia πŸ”— Birds

Casuarius is a genus of birds in the order Casuariiformes, whose members are the cassowaries (Tok Pisin: muruk, Indonesian: kasuari). It is classified as a ratite (flightless bird without a keel on its sternum bone) and is native to the tropical forests of New Guinea (Papua New Guinea and East Indonesia), Aru Islands (Maluku), and northeastern Australia.

Three species are extant: The most common, the southern cassowary, is the third-tallest and second-heaviest living bird, smaller only than the ostrich and emu. The other two species are represented by the northern cassowary and the dwarf cassowary; the northern cassowary is the most recently discovered and the most threatened. A fourth but extinct species is represented by the pygmy cassowary.

Cassowaries feed mainly on fruit, although all species are truly omnivorous and take a range of other plant foods, including shoots and grass seeds, in addition to fungi, invertebrates, and small vertebrates. Cassowaries are very wary of humans, but if provoked, they are capable of inflicting serious, even fatal, injuries to both dogs and people. The cassowary has often been labeled "the world's most dangerous bird".

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πŸ”— List of people claimed to be Jesus

πŸ”— Biography πŸ”— Lists πŸ”— Christianity πŸ”— Christianity/Jesus

This is a partial list of notable people who have been claimed, either by themselves or by their followers, in some way to be the reincarnation or incarnation of Jesus, or the Second Coming of Christ.

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πŸ”— Karatsuba Algorithm

πŸ”— Computing πŸ”— Mathematics πŸ”— Computing/Software πŸ”— Computing/Computer science

The Karatsuba algorithm is a fast multiplication algorithm. It was discovered by Anatoly Karatsuba in 1960 and published in 1962. It reduces the multiplication of two n-digit numbers to at most n log 2 ⁑ 3 β‰ˆ n 1.58 {\displaystyle n^{\log _{2}3}\approx n^{1.58}} single-digit multiplications in general (and exactly n log 2 ⁑ 3 {\displaystyle n^{\log _{2}3}} when n is a power of 2). It is therefore faster than the classical algorithm, which requires n 2 {\displaystyle n^{2}} single-digit products. For example, the Karatsuba algorithm requires 310 = 59,049 single-digit multiplications to multiply two 1024-digit numbers (n = 1024 = 210), whereas the classical algorithm requires (210)2 = 1,048,576 (a speedup of 17.75 times).

The Karatsuba algorithm was the first multiplication algorithm asymptotically faster than the quadratic "grade school" algorithm. The Toom–Cook algorithm (1963) is a faster generalization of Karatsuba's method, and the SchΓΆnhage–Strassen algorithm (1971) is even faster, for sufficiently large n.

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πŸ”— SchΓΆningen Spears

πŸ”— Germany πŸ”— Anthropology πŸ”— Palaeontology πŸ”— Archaeology

The SchΓΆningen spears are a set of eight wooden throwing spears from the Palaeolithic Age that were excavated between 1994 and 1998 in the open-cast lignite mine in SchΓΆningen, Helmstedt district, Germany, together with an associated cache of approximately 16,000 animal bones. The excavations took place under the management of Hartmut Thieme of the Lower Saxony State Service for Cultural Heritage (NLD).

Originally assessed as being between 380,000 and 400,000 years old, they represent the oldest completely preserved hunting weapons of prehistoric Europe so far discovered. As such they predate the age of Neanderthal Man (by convention taken to have emerged 300,000 years ago), and are associated with Homo heidelbergensis. The spears support the practice of hunting by archaic humans in Europe in the late Lower Paleolithic.

The age of the spears was estimated from their stratigraphic position, "sandwiched between deposits of the Elsterian and Saalian glaciations, and situated within a well-studied sedimentary sequence." More recently, thermoluminescence dating of heated flints in a deposit beneath that which contained the spears suggested that the spears were between 337,000 and 300,000 years old.

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πŸ”— Jim Lovell Has Died

πŸ”— Biography πŸ”— Aviation πŸ”— Spaceflight πŸ”— Military history πŸ”— Military history/Military aviation πŸ”— Military history/North American military history πŸ”— Military history/United States military history πŸ”— Biography/science and academia πŸ”— Military history/Military biography πŸ”— Biography/military biography πŸ”— Aviation/aerospace biography πŸ”— Military history/Cold War πŸ”— Pritzker Military Library πŸ”— Scouting πŸ”— Ohio πŸ”— Spaceflight/adopt an astronaut πŸ”— Cleveland

James Arthur Lovell Jr. ( LUV-Ι™l; March 25, 1928 – August 7, 2025) was an American astronaut, naval aviator, test pilot and mechanical engineer. In 1968, as command module pilot of Apollo 8, he became, with Frank Borman and William Anders, one of the first three astronauts to fly to and orbit the Moon. He then commanded the Apollo 13 lunar mission in 1970 which, after a critical failure en route, looped around the Moon and returned safely to Earth. He acted in a few movies, such as The Man Who Fell to Earth (1976) and Apollo 13 (1995; uncredited).

A graduate of the United States Naval Academy in Annapolis, Maryland, in the class of 1952, Lovell flew F2H Banshee night fighters. This included a Western Pacific deployment aboard the aircraft carrier USSΒ Shangri-La. In January 1958, he entered a six-month test pilot training course at the Naval Air Test Center at Naval Air Station Patuxent River, Maryland, with Class 20 and graduated at the top of the class. He was then assigned to Electronics Test, working with radar, and in 1960 he became the Navy's McDonnell Douglas F-4 Phantom II program manager. The following year he became a flight instructor and safety engineering officer at Naval Air Station Oceana in Virginia Beach, Virginia, and completed Aviation Safety School at the University of Southern California.

Lovell was not selected by NASA as one of the Mercury Seven astronauts due to a temporarily high bilirubin count. He was accepted in September 1962 as one of the second group of astronauts needed for the Gemini and Apollo programs. Prior to Apollo, Lovell flew in space on two Gemini missions, Gemini 7 (with Borman) in 1965 and Gemini 12 in 1966. He was the first person to fly into space four times. One of 24 people to have flown to the Moon, Lovell was the first to fly to the moon twice, and the only human to have done so without landing. He was a recipient of the Congressional Space Medal of Honor and the Presidential Medal of Freedom. He co-authored the 1994 book Lost Moon, on which the 1995 film Apollo 13 was based. Lovell was featured in a cameo appearance in the film.

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πŸ”— Heilmeier's Catechism: questions for every startup, every project.

πŸ”— Biography πŸ”— Biography/science and academia πŸ”— University of Pennsylvania

George Harry Heilmeier (May 22, 1936 – April 21, 2014) was an American engineer, manager, and a pioneering contributor to liquid crystal displays (LCDs), for which he was inducted into the National Inventors Hall of Fame. Heilmeier's work is an IEEE Milestone.