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A Rubik's Cube, whose manipulations form the Rubik's Cube group

A group, in mathematics, is a set together with an operation that combines any two of its elements to form a third element, in such a way that the operation is associative, an identity element exists, and every element has an inverse. These three conditions, called group axioms, are familiar from number systems. The ubiquity of groups in numerous areas—both within and outside mathematics—makes them a central organizational tool in contemporary mathematics. The concept of a group arose from the study of polynomial equations, starting with Évariste Galois in the 1830s. After contributions from other fields such as number theory and geometry, the group notion was generalized and firmly established around 1870. Today, group theory is a very active mathematical discipline that studies groups in their own right. Symmetry groups are widely applied in molecular chemistry and various physical disciplines. (Full article...)

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Mephistopheles and Margaretta

... that the sculpture Mephistopheles and Margaretta (pictured) is best seen with a mirror behind it?
... that American lawyer and politician Armistead Abraham Lilly was also a principal owner of Ruffner Hotel in Charleston, West Virginia, and resided in its penthouse?
... that almost everyone and everything that travels to Antarctica has to travel through one of five gateway cities?
... that Jonas Grethlein turned down chaired professorships at the universities of St Andrews and Cambridge?
... that in addition to creating milkshake products, Keventers Milkshake was also a major supplier of various milk products to the Indian Army for several decades up until the 1970s?
... that author Harriet Connor Brown testified to the United States Congress in 1921 and 1922 to eliminate funding for the Chemical Warfare Service?
... that the 1711 Missa Sanctae Caeciliae, the first composition by Jan Dismas Zelenka, who had come from Prague to play in the Dresden court orchestra, is a 45-minute mass?
... that the interactive cartoon Cat Burglar takes about 15 minutes to watch, but features 90 minutes of animation?

In the news

Endurance in 1915

The discovery of the wreck of the Endurance (pictured), sunk during Ernest Shackleton's Imperial Trans-Antarctic Expedition, is announced.
Yoon Suk-yeol is elected president of South Korea.
Australian cricketer Shane Warne dies at the age of 52.
An attack at a mosque in Peshawar, Pakistan, kills at least 63 people and injures more than 190 others.
The Winter Paralympics is held in Beijing, China.

On this day

March 14: New Year's Day (Sikhism); Commonwealth Day in the Commonwealth of Nations (2022); White Day in parts of East Asia; Pi Day

Catherine Cornaro

1309 – On Eid al-Fitr, the citizens of Granada stormed palaces in the city, deposing Sultan Muhammad III and placing his half-brother Nasr on the throne.
1489 – Catherine Cornaro (pictured), Queen of Cyprus, was forced to abdicate and sell the administration of the island to the Republic of Venice.
1885 – The Mikado, Gilbert and Sullivan's most frequently performed Savoy opera, debuted at the Savoy Theatre in London.
1969 – Edward M. Burke, the longest-serving alderman in the history of the Chicago City Council, was sworn into office.
1984 – Gerry Adams, leader of Sinn Féin, was seriously wounded in an assassination attempt by Ulster Freedom Fighters in central Belfast, Northern Ireland.

Charles Ammi Cutter (b. 1837)
Phil Vincent (b. 1908)
Lies Noor (d. 1961)

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Charles Darwin

The Darwin Medal is one of the medals awarded by the Royal Society of London for "distinction in evolution, biological diversity and developmental, population and organismal biology". It was established in 1885 after the transfer of the International Darwin Memorial Fund to the Royal Society. The Darwin Medal commemorates the work of English biologist Charles Darwin (pictured). The medal was first awarded in 1890 to Alfred Russel Wallace. It has been awarded over 60 times. It is currently awarded along with a grant of £2,000. From 1890 till 2018, it was awarded biennially. Since then, it is awarded annually. The diameter of the medal is 2+1⁄4 inch (5.7 cm). Made of silver, the obverse has Darwin's portrait, while the reverse has a wreath of plants with Darwin's name in Latin, "Carolus Darwin". It is surrounded by the years of his birth and death in Roman numerals. All citizens who have been residents of either the United Kingdom, Commonwealth of Nations, or the Republic of Ireland for more than three years are eligible for the medal. (Full list...)

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Today's featured picture

Haliotis clathrata, the lovely abalone, is a species of sea snail in the abalone family. It has a shell whose shape forms a logarithmic spiral. The species occurs in the western Pacific Ocean, on the coasts of Australia and the islands and mainland of Southeast Asia, as well as islands in the Indian Ocean such as Madagascar and Mauritius, and stretches of the East African coast. Clockwise from top left, this picture shows an empty H. clathrata shell in dorsal, lateral, ventral, front and back views. The shell is 3.2 centimetres (1.3 inches) in length, and was found in the Philippines.

Photograph credit: H. Zell

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