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🔗 Mathematics 🔗 Physics

The triple product rule, known variously as the cyclic chain rule, cyclic relation, cyclical rule, Euler's chain rule, or the reciprocity theorem, is a formula which relates partial derivatives of three interdependent variables. The rule finds application in thermodynamics, where frequently three variables can be related by a function of the form f(x, y, z) = 0, so each variable is given as an implicit function of the other two variables. For example, an equation of state for a fluid relates temperature, pressure, and volume in this manner. The triple product rule for such interrelated variables x, y, and z comes from using a reciprocity relation on the result of the implicit function theorem, and is given by

${\displaystyle \left({\frac {\partial x}{\partial y}}\right)\left({\frac {\partial y}{\partial z}}\right)\left({\frac {\partial z}{\partial x}}\right)=-1,}$

where each factor is a partial derivative of the variable in the numerator, considered to be a function of the other two.

The advantage of the triple product rule is that by rearranging terms, one can derive a number of substitution identities which allow one to replace partial derivatives which are difficult to analytically evaluate, experimentally measure, or integrate with quotients of partial derivatives which are easier to work with. For example,

${\displaystyle \left({\frac {\partial x}{\partial y}}\right)=-{\frac {\left({\frac {\partial z}{\partial y}}\right)}{\left({\frac {\partial z}{\partial x}}\right)}}}$

Various other forms of the rule are present in the literature; these can be derived by permuting the variables {x, y, z}.

🔗 History 🔗 Physics 🔗 Telecommunications 🔗 Skepticism 🔗 Astronomy 🔗 History of Science 🔗 Physics/History 🔗 Paranormal

The Wow! signal was a strong narrowband radio signal received on August 15, 1977, by Ohio State University's Big Ear radio telescope in the United States, then used to support the search for extraterrestrial intelligence. The signal appeared to come from the direction of the constellation Sagittarius and bore the expected hallmarks of extraterrestrial origin.

Astronomer Jerry R. Ehman discovered the anomaly a few days later while reviewing the recorded data. He was so impressed by the result that he circled the reading on the computer printout, "6EQUJ5", and wrote the comment "Wow!" on its side, leading to the event's widely used name.

The entire signal sequence lasted for the full 72-second window during which Big Ear was able to observe it, but has not been detected since, despite several subsequent attempts by Ehman and others. Many hypotheses have been advanced on the origin of the emission, including natural and human-made sources, but none of them adequately explains the signal.

Although the Wow! signal had no detectable modulation—a technique used to transmit information over radio waves—it remains the strongest candidate for an alien radio transmission ever detected.

🔗 Psychology

Bedtime procrastination or revenge bedtime procrastination is a psychological phenomenon in which people stay up later than they desire in an attempt to have control over the night because they perceive themselves (perhaps subconsciously) to lack influence over events during the day.

🔗 Internet culture

Lamer is a jargon or slang name originally applied in cracker and phreaker culture to someone who did not really understand what they were doing. Today it is also loosely applied by IRC, BBS, demosceners, and online gaming users to anyone perceived to be contemptible. In general, the term has come to describe someone who is willfully ignorant of how things work. It is derived from the word "lame".

A lamer is sometimes understood to be the antithesis of a hacker. While a hacker strives to understand the mechanisms behind what they use, even when such extended knowledge would have no practical value, a lamer only cares to learn the bare minimum necessary to operate the device in the way originally intended.

🔗 Physics 🔗 Physics/History 🔗 University of Oxford 🔗 University of Oxford/University of Oxford (colleges)

The Oxford Electric Bell or Clarendon Dry Pile is an experimental electric bell that was set up in 1840 and which has run nearly continuously ever since. It was one of the first pieces purchased for a collection of apparatus by clergyman and physicist Robert Walker. It is located in a corridor adjacent to the foyer of the Clarendon Laboratory at the University of Oxford, England, and is still ringing, though inaudibly due to being behind two layers of glass.

🔗 Mexico 🔗 Radio

A border blaster is a broadcast station that, though not licensed as an external service, is, in practice, used to target another country. The term "border blaster" is of North American origin, and usually associated with Mexican AM stations whose broadcast areas cover large parts of the United States, and United States border AM stations covering large parts of Canada. Conceptually similar European broadcasting included some pre-World War II broadcasting towards the United Kingdom, "radio périphérique" around France and the U.S. government-funded station Radio Free Europe, targeting European countries behind the Iron Curtain.

With broadcasting signals far more powerful than those of U.S. stations, the Mexican border blasters could be heard over large areas of the U.S. from the 1940s to the 1970s, often to the great irritation of American radio stations, whose signals could be overpowered by their Mexican counterparts. These are also sometimes referred to as X stations for their call letters: Mexico assigns callsigns beginning with XE or XH to broadcast stations.

On November 9, 1972, in Washington, D.C., the United States and Mexico signed an "Agreement Concerning Frequency Modulation Broadcasting in the 87.5 to 108 MHz Band". Since then, in the FM band power levels and frequency assignments have been set by mutual agreement between the two countries. AM radio border blasters still exist, though they are largely ignored due to the decline of AM radio in the U.S. and in Mexico. There are several such stations licensed by Mexico's Secretariat of Communications and Transportation using transmitters with an effective radiated power similar to those of major licensed commercial stations located within the U.S.

🔗 Robotics 🔗 Japan 🔗 Japan/History 🔗 Japan/Science and technology

Gakutensoku (學天則, Japanese for "learning from the laws of nature") was the first robot to be built in East Asia and was created in Osaka in the late 1920s. The robot was designed and manufactured by biologist Makoto Nishimura.

🔗 England 🔗 United Kingdom 🔗 Politics of the United Kingdom 🔗 Elections and Referendums 🔗 East Anglia

A by-election for the United Kingdom parliamentary constituency of Clacton is being held on 13 August 2026, following the resignation of Nigel Farage, its member of Parliament. Farage, who is the leader of Reform UK, had represented Clacton since the 2024 general election. He announced on 7 July 2026 that he would vacate his seat to trigger a by-election and re-contest the constituency; his resignation was accepted the next day. The announcement came amid parliamentary scrutiny of Farage's personal finances, and allegations concerning undeclared gifts and support.

The Labour Party, the Conservative Party, the Liberal Democrats, the Green Party and Restore Britain are not contesting the by-election, leaving Count Binface, a novelty candidate, as the main challenger to Farage. Thirty-two other candidates were nominated, with the total of 34 breaking the record – previously set in 2008 – for the most candidates standing in any UK parliamentary election, including three from the Official Monster Raving Loony Party.

🔗 Philosophy 🔗 Philosophy/Philosophical literature 🔗 Books 🔗 Philosophy/Contemporary philosophy 🔗 Philosophy/Continental philosophy

Simulacra and Simulation (French: Simulacres et Simulation) is a 1981 philosophical treatise by Jean Baudrillard, in which the author seeks to examine the relationships between reality, symbols, and society, in particular the significations and symbolism of culture and media involved in constructing an understanding of shared existence.

Simulacra are copies that depict things that either had no original, or that no longer have an original. Simulation is the imitation of the operation of a real-world process or system over time.

🔗 Color

Olo is an imaginary color that can only be seen using specialized tools that exclusively activate the M cone cells on the retina.

It is impossible to view olo under normal viewing conditions, due to the overlapping sensitivities of M cone cells and S and L cone cells in all wavelengths of visible light that evoke them. In other words, there is no monochromatic stimulus (the purest type of stimulus that humans can perceive) that activates only the M cones. This means that olo is outside the visible gamut. To get around this, researchers mapped a portion of the retina and individually identified each cone cell as either an S, M, or L cone. They then used lasers to deliver tiny doses of light attempting to target specifically the M cone cells, mostly avoiding the S and L cone cells.

The researchers who experienced olo said that the closest color to olo in the sRGB gamut is hexadecimal code #00FFCC.