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15

He synchronised them to the solar zenith. Eratosthenes knew that on the day of the summer solstice, the sun passed vertically above Syene, which lies very close to the Tropics of Cancer. As the traditional account goes, the sun was directly above a vertical well at Syene, whereas at Alexandria the columns of the Library always leaves a shadow. Either way, ...


12

The oldest confirmed use of any version of this quote that I was able to find is from Ray Cummings' short story The Time Professor, published in the Jan. 8, 1921 issue of Argosy All-Story Weekly (thanks to mgkrebbs for pointing this one out): "I do know what time is," Tubby declared. He paused. "Time," he added slowly -- "time is what keeps everything ...


8

Simple. While the earth moves around the year, the sun seemingly moves around between the Tropic of Cancer (north) and the Tropic of the Capricorn (south). In the north this is begin of summer and the sun reaches the highest point. The first city where the deep well exists is the city of Syene (now Assuan) which is almost exactly on the Tropic of Cancer, ...


8

The Standard Model of particle physics got its name from the late Sam Treiman. It was first coined in 1975 when Treiman, together with long time friend Abraham Pais, published a paper in which they used "standard model" to reference the four quarks theory. The term 'Standard Model' was first coined by Pais and Treiman in (1975), with reference to the ...


6

In the words of one Richard Feynman, from Chapter 28 of The Feynman Lectures in Physics Vol. 1: Maxwell noted that the equations for the laws that had been discovered up to this time were mutually inconsistent when he tried to put them together, and in order for the whole system to be consistent he had to add another term to the equations. With this new ...


6

TL;DR According to Roger Hart [1], this view is widely held but wrong. He cites, among (many) others, Needham who speaks of a decay and Mikami who considers Ming scholars to be degenerate. The alleged reason is not a decree, but societal and technical characteristics of the society. This view is slow to revert, because almost no one studies Ming mathematics,...


5

The story with Hooke--Newton correspondence was well-known at the time of Newton. Newton consciously belittled Hooke's contribution, against the advise of some friends. He also claimed that he had this idea long before Hooke, and this is probably correct. I do not think anyone would call Newton a plagiarist, but his behavior with respect to several ...


4

No. Several people had the idea of an attractive force, and some of them of an inverse square law. Newton worked the idea out in detail, and showed that it produced results that matched the observations of the solar system: he made gravity into a proper scientific theory, rather than a vague hypothesis. Wikipedia's article on Hooke has a good account of ...


4

Making use of the Magnus effect in the era of round cannonballs fired from unrifled cannon was impractical. The rotation of the ball is caused by minor irregularities on the surface of the ball, and in the barrel of the gun. That means that the rotation is on a random axis, and at a random speed, or certainly should be. If it isn't, the cannon has a ...


3

The principle of inertia Galileo was an early and prominent advocate of the principle of inertia -- roughly stated, that things naturally keep moving rather than naturally slowing down. In his 1624 reply to Ingoli, he described a specific experiment, which he claimed to have carried out, in which a rock was dropped from the mast of a moving ship, and struck ...


3

On John Buridan's page in the Stanford Encyclopedia of Philosophy, we have the citation: Buridan, John, 1588 (actually 1518), In Metaphysicen Aristotelis Questiones argutissimae, Paris. Rpr. 1964, as Kommentar zur Aristotelischen Metaphysik, Frankfurt a. M.: Minerva. [QM] which suggests that the 'QM' in your citation is 'In Metaphysicen Aristotelis ...


2

For firearms the main Magnus effect is on range, in particular the range at which the bullet drops from supersonic to subsonic. (The direction of crosswind relative to orientation of barrel rifling either increases or decreases range - similar to a topspin/backspin effect.) Thus it is usually only necessary to account for in extreme long-range sniping. This ...


2

The origins of the term are somewhat obscure. In the book "The Rise of the Standard Model: Particle Physics in the 1960's and 1970's," the authors write: In the late 1970s elementary particle physicists began speaking of the "Standard Model" as basic theory of matter.... The model is referred to as "standard," because it provides a theory of ...


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