Have a deep view into what people are curious about.

🔗 Technology 🔗 Military history 🔗 Military history/Military science, technology, and theory 🔗 Military history/Maritime warfare

Communication with submarines is a field within military communications that presents technical challenges and requires specialized technology. Because radio waves do not travel well through good electrical conductors like salt water, submerged submarines are cut off from radio communication with their command authorities at ordinary radio frequencies. Submarines can surface and raise an antenna above the sea level, then use ordinary radio transmissions, however this makes them vulnerable to detection by anti-submarine warfare forces. Early submarines during World War II mostly traveled on the surface because of their limited underwater speed and endurance; they dove mainly to evade immediate threats. During the Cold War, however, nuclear-powered submarines were developed that could stay submerged for months. Transmitting messages to these submarines is an active area of research. Very low frequency (VLF) radio waves can penetrate seawater a few hundred feet, and many navies use powerful VLF transmitters for submarine communications. A few nations have built transmitters which use extremely low frequency (ELF) radio waves, which can penetrate seawater to reach submarines at operating depths, but these require huge antennas. Other techniques that have been used include sonar and blue lasers.

🔗 United States 🔗 Law

In re Bilski, 545 F.3d 943, 88 U.S.P.Q.2d 1385 (Fed. Cir. 2008), was an en banc decision of the United States Court of Appeals for the Federal Circuit (CAFC) on the patenting of method claims, particularly business methods. The Federal Circuit court affirmed the rejection of the patent claims involving a method of hedging risks in commodities trading. The court also reiterated the machine-or-transformation test as the (meaning sole) applicable test for patent-eligible subject matter, and stated that the test in State Street Bank v. Signature Financial Group should no longer be relied upon.

The Supreme Court of the United States issued an opinion on appeal (as Bilski v. Kappos) that affirmed the judgment of the CAFC, but revised many aspects of the CAFC's decision. In its decision, handed down on June 28, 2010, the Supreme Court rejected the machine-or-transformation test as the sole test of process patent eligibility based on an interpretation of the language of § 101. The majority, however, had high praise for the Federal Circuit opinions, advising that "[s]tudents of patent law would be well advised to study these scholarly opinions."

🔗 Horse racing

Potoooooooo or variations of Pot-8-Os (1773 – November 1800) was an 18th-century thoroughbred racehorse who won over 30 races and defeated some of the greatest racehorses of the time. He went on to be a sire. He is now best known for the unusual spelling of his name, pronounced 'Potatoes'.

🔗 Finance & Investment 🔗 Economics

A perpetual bond, also known colloquially as a perpetual or perp, is a bond with no maturity date, therefore allowing it to be treated as equity, not as debt. Issuers pay coupons on perpetual bonds forever, and they do not have to redeem the principal. Perpetual bond cash flows are, therefore, those of a perpetuity.

🔗 Architecture 🔗 Greece 🔗 Urban studies and planning 🔗 Greece/Athens

The Athens Charter (French: Charte d'Athènes, Greek: Χάρτα των Αθηνών) was a 1933 document about urban planning published by the Swiss architect Le Corbusier. The work was based upon Le Corbusier’s Ville Radieuse (Radiant City) book of 1935 and urban studies undertaken by the Congrès International d'Architecture Moderne (CIAM) in the early 1930s.

The Charter got its name from location of the fourth CIAM conference in 1933, which, due to the deteriorating political situation in Russia, took place on the S.S. Patris bound for Athens from Marseille. This conference is documented in a film commissioned by Sigfried Giedion and made by his friend Laszlo Moholy-Nagy: "Architects' Congress."

The Charter had a significant impact on urban planning after World War II.

🔗 Mathematics

The number e is a mathematical constant approximately equal to 2.71828 and is the base of the natural logarithm: the unique number whose natural logarithm is equal to one. It is the limit of (1 + 1/n)ⁿ as n approaches infinity, an expression that arises in the study of compound interest. It can also be calculated as the sum of the infinite series

${\displaystyle e=\sum \limits _{n=0}^{\infty }{\frac {1}{n!}}={\frac {1}{1}}+{\frac {1}{1}}+{\frac {1}{1\cdot 2}}+{\frac {1}{1\cdot 2\cdot 3}}+\cdots }$

The constant can be characterized in many different ways. For example, it can be defined as the unique positive number a such that the graph of the function y = a^x has unit slope at x = 0. The function f(x) = e^x is called the (natural) exponential function, and is the unique exponential function equal to its own derivative. The natural logarithm, or logarithm to base e, is the inverse function to the natural exponential function. The natural logarithm of a number k > 1 can be defined directly as the area under the curve y = 1/x between x = 1 and x = k, in which case e is the value of k for which this area equals one (see image). There are alternative characterizations.

e is sometimes called Euler's number after the Swiss mathematician Leonhard Euler (not to be confused with γ, the Euler–Mascheroni constant, sometimes called simply Euler's constant), or as Napier's constant. However, Euler's choice of the symbol e is said to have been retained in his honor. The constant was discovered by the Swiss mathematician Jacob Bernoulli while studying compound interest.

The number e has eminent importance in mathematics, alongside 0, 1, π, and i. All five of these numbers play important and recurring roles across mathematics, and these five constants appear in one formulation of Euler's identity. Like the constant π, e is also irrational (i.e. it cannot be represented as ratio of integers) and transcendental (i.e. it is not a root of any non-zero polynomial with rational coefficients). The numerical value of e truncated to 50 decimal places is

🔗 United States 🔗 Religion 🔗 Islam 🔗 Discrimination 🔗 African diaspora 🔗 United States/Texas 🔗 Religion/Interfaith 🔗 Dallas-Fort Worth 🔗 Islam/Islam and Controversy

On September 14, 2015, 14-year-old Ahmed Mohamed was arrested at MacArthur High School in Irving, Texas, for bringing a disassembled digital clock to school. The incident ignited allegations of racial profiling and Islamophobia from many media sources and commentators.

The episode arose when Mohamed reassembled the parts of a digital clock in an 8-inch (20 cm) pencil container and brought it to school to show his teachers. His English teacher thought the device resembled a bomb, confiscated it, and reported him to the principal. The local police were called, and they questioned him for an hour and a half. He was handcuffed, taken into custody and transported to a juvenile detention facility, where he was fingerprinted and his mug shot was taken. He was then released to his parents. According to local police, they arrested him because they initially suspected he may have purposely caused a bomb scare. The case was not pursued further by the juvenile justice authorities, but he was suspended from school.

Following the incident, the police determined Mohamed had no malicious intent, and he was not charged with any crime. News of the incident went viral – initially on Twitter – with allegations by commentators that the actions of the school officials and police were due to their stereotyping of Mohamed based on his Sudanese ancestry and Muslim faith. Afterwards, U.S. President Barack Obama as well as other politicians, activists, technology company executives, and media personalities commented about the incident. Many of them praised Mohamed for his ingenuity and creativity, and he was invited to participate in a number of high-profile events related to encouraging youth interest in science and technology. Although Mohamed was cleared in the final police investigation, he became the subject of conspiracy theories – many of them contradictory, citing no evidence, and conflicting with established facts – which claimed that the incident was a deliberate hoax.

On November 23, 2015, Ahmed's family threatened to sue the City of Irving and the school district for civil rights violations and physical and mental anguish unless they received written apologies and compensation of $15 million. This lawsuit was dismissed in May 2017 for lack of evidence. The family also sued conservative talk show hosts Glenn Beck, Ben Shapiro, and another Fox News commentator for lesser amounts on the grounds of defamation of character. Both cases were dismissed with prejudice for First Amendment free speech reasons. In late 2015, his family decided to accept a scholarship from the Qatar Foundation and move to Qatar.

🔗 Politics 🔗 Socialism 🔗 Holidays 🔗 Organized Labour 🔗 Neopaganism

May Day is a public holiday in some regions, usually celebrated on 1 May or the first Monday of May. It is an ancient festival marking the first day of summer, and a current traditional spring holiday in many European cultures. Dances, singing, and cake are usually part of the festivities.

In 1889, May Day was chosen as the date for International Workers' Day by the socialists and communists of the Second International, as well as anarchists, labor activists, and leftists in general around the world, to commemorate the Haymarket affair in Chicago and the struggle for an eight-hour working day. International Workers' Day is also called "May Day", but it is a different celebration from the traditional May Day.

🔗 Biography 🔗 Philosophy 🔗 Biography/science and academia 🔗 Philosophy/Philosophers 🔗 Norway 🔗 Philosophy/Ethics

Arne Dekke Eide Næss ( AR-nə NESS; Norwegian: [ˈnɛsː]; 27 January 1912 – 12 January 2009) was a Norwegian philosopher who coined the term "deep ecology" and was an important intellectual and inspirational figure within the environmental movement of the late twentieth century. Næss cited Rachel Carson's 1962 book Silent Spring as being a key influence in his vision of deep ecology. Næss combined his ecological vision with Gandhian nonviolence and on several occasions participated in direct action.

Næss averred that while western environmental groups of the early post-war period had raised public awareness of the environmental issues of the time, they had largely failed to have insight into and address what he argued were the underlying cultural and philosophical background to these problems. Naess believed that the environmental crisis of the twentieth century had arisen due to certain unspoken philosophical presuppositions and attitudes within modern western developed societies which remained unacknowledged.

He thereby distinguished between what he called deep and shallow ecological thinking. In contrast to the prevailing utilitarian pragmatism of western businesses and governments, he advocated that a true understanding of nature would give rise to a point of view that appreciates the value of biological diversity, understanding that each living thing is dependent on the existence of other creatures in the complex web of interrelationships that is the natural world.

🔗 Time 🔗 Switzerland 🔗 Trains 🔗 Trains/Stations

The Swiss railway clock was designed in 1944 by Hans Hilfiker, a Swiss engineer and Swiss Federal Railways (SBB) employee, together with Moser-Baer, a Swiss clock manufacturer, for use by the SBB as a station clock. In 1953, Hilfiker added a red second hand in the shape of the baton used by train dispatch staff., giving the clock its current appearance.