Author Archives: John F. Lindner

After the conference in Switzerland, I stopped in Tübingen to visit Otto Rössler. Nearly everyone who learned about nonlinear systems knows the nowadays named Rössler attractor and his work in chaos theory in the 1970s. For the last four years … … Continue reading →

As a kid, pouring over the Guinness Book of World Records, I was struck by the longest flight; instead of lasting hours, as I would have guessed, it lasted more than two months! Nearly 66 years later, it remains one … Continue reading → Continue reading →

When viewing space photography, such as Apollo or International Space Station photos, people often ask, “Where are the stars?” Typically such photos properly expose the relatively bright lunar or space station surfaces and consequently unde… Continue reading →

When searching for prime numbers, the next prime number is no larger than twice the current number. Postulated by Joseph Bertrand, first proved by Pafnuty Chebyshev, I present an elementary proof based on one by the teenage Paul Erdős. Erdős … Co… Continue reading →

Up early this morning to watch the spectacular fourth integrated flight test of SpaceX’s Superheavy Starship, the largest rocket ever built. Each IFT has greatly improved on the previous one, and the fourth was no exception. For the first time, &… Continue reading →

John Chase, the head of the Walter Johnson High School Math Department, in Maryland, near Washington DC, liked my Stegosaurus variation of the Spectre monotile so much that he had his students paint it on the wall of their math … Continue reading… Continue reading →

I still retain the personal, anecdotal memory of my first encounter with the spelling of people. I was learning to read, and I got cat, mat, pat. I got lot, pot, dot. But I did not get people. Why the o, and… Continue reading →

Thousands of years ago, ancient astronomers like Eratosthenes and Aristarchus combined careful observations with simple mathematics to measure the solar system, especially the diameters D of Earth, Luna (Earth’s moon), Sol (Earth’s star, th… Continue reading →

Saturday, March 8, 2008. A heavy snow, one of the heaviest I remember, shuts down the city of Wooster. Streets are undriveable, so I walk to Taylor Hall, getting snow in my boots. Taylor is deserted, as the College has … Continue reading → Continue reading →

The pressure and temperature near the surface of Venus is so high that its carbon dioxide atmosphere is a supercritical fluid, a global ocean of a remarkable state of matter, which fills any container like a gas but is as … Continue reading → Continue reading →