The Rhind Mathematical Papyrus is a major surviving record of ancient Egyptian mathematics, copied by the scribe Ahmes around 1550 BC from an older text associated with the reign of Amenemhat III. Written in hieratic, it was produced during Egypt’s Second Intermediate Period and is dated to the reign of the Hyksos king Apophis. A note on its reverse may record events near the end of Hyksos rule. Scottish antiquarian Alexander Henry Rhind bought the papyrus in Luxor in 1858; most of it is now in the British Museum, with fragments in the Brooklyn Museum. A section is missing, and parts of its mathematical text remain incompletely interpreted.
Its tables and 91 problems show mathematics applied to calculation, measurement and practical administration. A table expresses 2 divided by odd numbers as sums of unit fractions; other exercises cover dividing bread among workers, multiplication, subtraction, linear equations and arithmetic progressions. Geometry problems calculate the volumes of granaries and the areas of circles, rectangles, triangles and trapezoids. For a circle, the papyrus uses a method equivalent to taking π as 256/81, an approximation within one percent of its modern value. Its final geometry problems determine pyramid slope using the seked, the horizontal run for a given vertical rise. The collection demonstrates a systematic, example-based mathematical tradition built around fractions, units of measurement and procedures for solving practical problems.
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Italian farmer Claudio Grossi discovered and planted seeds from his great-grandfather’s attic, growing unusually tall wheat with seven ears per stalk and multicolored kernels. The ancient grain attracted interest as a potential answer to modern agricultural challenges. (smithsonianmag.com)
Obesity rates rose dramatically over the past century, even though earlier generations ate plenty of butter and other high-fat foods. The shift accelerated in recent decades, and familiar explanations like diet and exercise do not fully account for it. (slimemoldtimemold.com)
Voyager 1’s team completed power-saving equipment swaps that will keep its remaining science instruments operating longer despite the probe losing about four watts each year. A 48-hour communications pause on Oct. 20 ended on its own before engineers sent troubleshooting commands. (jpl.nasa.gov)
![The lithium hypothesis of obesity [video]](https://hntoday.pixelshot.io/screenshots/20261031/99348d6522c847df_tn.jpeg)
The video is titled “The lithium hypothesis of obesity.” The provided page contains no information about the hypothesis or its evidence. (youtube.com)
Electrifying transport, heating and industry could halve global energy demand by replacing an inefficient fossil-fuel system that wastes much of its energy as heat. Oxford professor Jan Rosenow also discusses grid demands, battery recycling, China’s solar growth and how electrification can strengthen energy security. (fullycharged.show)
The linked paper’s title proposes that Alzheimer’s disease may begin in the nose and be caused by aluminosilicates. Its contents could not be accessed, so the claim cannot be verified from the provided text. (sciencedirect.com)
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