Author Archives: John F. Lindner

About John F. Lindner

John F. Lindner was born in Sleepy Hollow New York and educated at the University of Vermont and Caltech. He is a professor of physics and astronomy at The College of Wooster. He has enjoyed multiple yearlong sabbaticals at Georgia Tech, University of Portland, University of Hawai'i, and North Carolina State University. His research interests include nonlinear dynamics, celestial mechanics, and variable stars.

Losing Betelgeuse

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

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Continental Bridge

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

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Table of Nuclides

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

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Intrepid-Surveyor

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

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Relaxing Fermat

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

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Stainless Steel Starship

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

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After the Moonwalk

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

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“Contact Light”

Our TV is broken, so Aunt Nora invites us to her apartment. (Aunt Nora isn’t really our aunt, but she introduced our parents to each other, so that’s what we call her.) My brother Jim and I lie on the … Continue reading
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Wooster Epicycles

Just as a vector is the sum of its components, a mechanical motion a combination of its normal mode motions, a quantum state a superposition of its eigenstates, any “nice” function is a Fourier sum of real or complex sinusoids [latex]e^{i … Continue reading
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Redefining SI

Today the SI (Système international d’unités) base units are redefined. The following are now exact. Memorize these numbers! Cs-133 transition frequency constant [latex]Δν_{\text{Cs}} = 9\,192\,631\,770~\text{s}^{−1}[/latex] defines the second. Then light speed constant [latex]c = 299\,792\,458~\text{m}\cdot\text{s}^{−1}[/latex] defines the meter. Then Planck’s constant [latex]h = 6.626\,070\,15\times … Continue reading
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