Author Archives: John F. Lindner

A second ago, I finished this blog entry. A kilosecond ago, I wrote it. A megasecond ago, I isolated myself against the 2020 pandemic. A gigasecond ago, I began my career at The College of Wooster, which I celebrate today, … Continue reading → Continue reading →

Although almost all ordinary mass effectively arises from the kinetic and binding energy of quarks and gluons bound to protons and neutrons in atomic nuclei, the Higgs mechanism does endow some particles like quarks and weakons with intrinsic masses. H… Continue reading →

In 1945, science fiction author Arthur C. Clarke published “Extra-Terrestrial Relays – Can Rocket Stations Give Worldwide Radio Coverage?” in Wireless World magazine. Clarke calculated a special orbit, about 36 000 km above the equator with… Continue reading →

At my computer Tuesday evening, I receive a message from a university physics chat that is both thrilling and chilling: LIGO and Virgo report a “burst” gravitational wave event, possibly due to a core-collapse supernova (or a binary collisi… Continue reading →

I remember looking at a classroom map of Earth and thinking the continents seem like puzzle pieces, especially north and south America in the west and Europe and Africa in the east. I mentally fit them together. Later I learned … Continue reading… Continue reading →

As of 2019, we have identified or synthesized 118 distinct elements with Z protons, but about 2900 distinct nuclides with N neutrons (where atom is to element as nucleus is to nuclide). The start of my version of the table … Continue reading → Continue reading →

Fifty years ago, Apollo 12 landed within sight of another spacecraft, a dramatic demonstration of pinpoint landing capability. While Dick Gordon orbited Luna in the command module Yankee Clipper, Pete Conrad and Al Bean left the lunar module Intrepid a… Continue reading →

In 1637, while reading a copy of Diophantus’s Arithmetica, Pierre de Fermat famously scribbled “Cubum autem in duos cubos, aut quadratoquadratum in duos quadratoquadratos & generaliter nullam in infinitum ultra quadratum potestatem in d… Continue reading →

Welders in a Texas swamp have built a starship. But don’t bet against SpaceX. Starship is a prototype upper stage for a next-generation, fully reusable, two-stage-to-obit launch vehicle designed to explore and colonize Mars. Starship is made from… Continue reading →

Most people are familiar with Neil Armstrong’s iconic photograph of Buzz Aldrin during the first moon walk. Much less well-known are this pair of photographs taken just after the moon walk. To my eyes, Armstrong seems exhausted but happy; Aldrin … Continue reading →