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"Belling the Cat" is a fable also known under the titles "The Bell and the Cat" and "The Mice in Council". Although often attributed to Aesop, it was not recorded before the Middle Ages and has been confused with the quite different fable of Classical origin titled The Cat and the Mice. In the classificatory system established for the fables by B. E. Perry, it is numbered 613, which is reserved for Mediaeval attributions outside the Aesopic canon.

IBM and the Holocaust: The Strategic Alliance between Nazi Germany and America's Most Powerful Corporation is a book by investigative journalist Edwin Black which details the business dealings of the American-based multinational corporation International Business Machines (IBM) and its German and other European subsidiaries with the government of Adolf Hitler during the 1930s and the years of World War II. In the book, published in 2001, Black outlined the way in which IBM's technology helped facilitate Nazi genocide through generation and tabulation of punch cards based upon national census data.

The long s (ſ) is an archaic form of the lower case letter s. It replaced the single s, or the first s in a double s (e.g. "ſinfulneſs" for "sinfulness" and "ſucceſs" for "success"). The long s is the basis of the first half of the grapheme or the German alphabet ligature letter ß, which is known as the Eszett. The modern letterform is known as the short, terminal, or round s.

The Oh-My-God particle was the highest-energy cosmic ray detected at the time (15 October 1991) by the Fly's Eye detector in Dugway Proving Ground, Utah, US. Its energy was estimated as (3.2±0.9)×10²⁰ eV, or 51 J. This is 20 million times more energetic than the highest energy measured in electromagnetic radiation emitted by an extragalactic object and 10²⁰ (100 quintillion) times the photon energy of visible light, equivalent to a 142-gram (5 oz) baseball travelling at about 26 m/s (94 km/h; 58 mph). Although higher energy cosmic rays have been detected since then, this particle's energy was unexpected, and called into question theories of that era about the origin and propagation of cosmic rays.

Assuming it was a proton, this particle traveled at 99.99999999999999999999951% of the speed of light, its Lorentz factor was 3.2×10¹¹ and its rapidity was 27.1. At this speed, if a photon were travelling with the particle, it would take over 215,000 years for the photon to gain a 1 cm lead as seen in Earth's reference frame.

The energy of this particle is some 40 million times that of the highest energy protons that have been produced in any terrestrial particle accelerator. However, only a small fraction of this energy would be available for an interaction with a proton or neutron on Earth, with most of the energy remaining in the form of kinetic energy of the products of the interaction. The effective energy available for such a collision is √2Emc², where E is the particle's energy and mc² is the mass energy of the proton. For the Oh-My-God particle, this gives 7.5×10¹⁴ eV, roughly 60 times the collision energy of the Large Hadron Collider.

While the particle's energy was higher than anything achieved in terrestrial accelerators, it was still about 40 million times lower than the Planck energy. Particles of such energy would be required in order to explore the Planck scale. A proton with that much energy would travel 1.665×10¹⁵ times closer to the speed of light than the Oh-My-God particle. As viewed from Earth it would take about 3.579×10²⁰ years, or 2.59×10¹⁰ times the current age of the universe, for a photon to gain a 1 cm lead over a Planck energy proton as observed in Earth's reference frame.

Since the first observation, at least 72 similar (energy > 5.7×10¹⁹ eV) events have been recorded, confirming the phenomenon. These ultra-high-energy cosmic ray particles are very rare; the energy of most cosmic ray particles is between 10 MeV and 10 GeV. More recent studies using the Telescope Array have suggested a source for the particles within a 20-degree radius "warm spot" in the direction of the constellation Ursa Major.

The Peter principle is a concept in management developed by Laurence J. Peter, which observes that people in a hierarchy tend to rise to their "level of incompetence": employees are promoted based on their success in previous jobs until they reach a level at which they are no longer competent, as skills in one job do not necessarily translate to another. The concept was elucidated in the book The Peter Principle (William Morrow and Company, 1969) by Dr Peter and Raymond Hull.

Peter and Hull intended the book to be satire, but it became popular as it was seen to make a serious point about the shortcomings of how people are promoted within hierarchical organizations. Hull wrote the text, based on Peter's research. The Peter principle has been the subject of much subsequent commentary and research.

Dagen H (H day), today usually called "Högertrafikomläggningen" ("The right-hand traffic diversion"), was the day on 3 September 1967, in which the traffic in Sweden switched from driving on the left-hand side of the road to the right. The "H" stands for "Högertrafik", the Swedish word for "right traffic". It was by far the largest logistical event in Sweden's history.

TV detector vans are vans, which, according to the BBC, contain equipment that can detect the presence of television sets in use. The vans are operated by contractors working for the BBC, to enforce the television licensing system in the UK, the Channel Islands and on the Isle of Man. The veracity of their operation has been called into question in the media.

Capitol Hill's mystery soda machine was a Coke vending machine in Capitol Hill, Seattle, that was in operation since at least the early 1990s until its disappearance in 2018. It is unknown who stocked the machine.

Goodhart's law is an adage named after economist Charles Goodhart, which has been phrased by Marilyn Strathern as "When a measure becomes a target, it ceases to be a good measure." One way in which this can occur is individuals trying to anticipate the effect of a policy and then taking actions that alter its outcome.

A toast sandwich is a sandwich made with two slices of bread in which the filling is a thin slice of toasted bread, which can be heavily buttered. An 1861 recipe says to add salt and pepper to taste.