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 an emeritus professor of physics and astronomy at The College of Wooster and a visiting professor at North Carolina State University. He has enjoyed multiple yearlong sabbaticals at Georgia Tech, University of Portland, University of Hawai'i, and NCSU. His research interests include nonlinear dynamics, celestial mechanics, and neural networks.

Punch it, SpaceX

She’s not looking up at the sky; she’s looking down at it. I am excitedly following the Inspiration4 spaceflight and its crew of four enthusiastic and diverse private citizens: Jared Isaacman, Hayley Arceneaux, Christopher Sembroski, and Si… Continue reading

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Dandelin Spheres

In 1609, Johannes Kepler first described how planets orbit the sun in ellipses. Kepler understood an ellipse as both the locus of points whose distances from two foci sum to a constant and as the intersection of a cone and a plane. But how … Cont… Continue reading

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Grad Schools

Wooster physics graduates do many things after Wooster, including graduate work. Below is a map of some of the graduate schools they have attended, one dimension of the influence of our department. If you are a recent Wooster physics graduate … C… Continue reading

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For Teague

Sadly and unexpectedly Wooster physics senior Teague Curless ’21 died yesterday. I was fortunate to teach Teague some physics, especially in my Nonlinear Dynamics class last spring. Teague’s semester project beautifully illustrated chaos in… Continue reading

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21st Century Skyscraper

Recently at its Boca Chica launch site, SpaceX stacked a Starship on a Superheavy booster to briefly form history’s largest rocket, dwarfing the Apollo Saturn V. Both a fit-check and a statement, SpaceX released the photograph below in black &#38… Continue reading

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Spinors

Fermions like electrons, protons, and neutrons inhabit a 720° world: 360° rotations negate their quantum states, but 720° rotations restore them. In Dirac notation [latex display=”true”]R_{2\pi}|\psi \rangle = -|\psi \rangle = e^{… Continue reading

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Squares & Cubes

Marvelously, the square of the sum of natural numbers is the sum of their cubes! Equivalently, the sum of their cubes is the square of their sum. This mathematical gem is attributed to Nicomachus of Gerasa who lived almost 2000 years … Continue r… Continue reading

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Transition

As I transition to emeritus status tomorrow, I reflect on 33 years at Wooster. I am thankful for the freedom I’ve had to design my own courses, including eight first-year seminars; for the flexibility to explore a wide range of … Continue r… Continue reading

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Archimedes & Euler

Consider a complex function that is its own derivative normalized to one at zero. Its Taylor series expansion [latex display=”true”]f(z) = \sum_{n=0}^\infty \frac{f^{(n)}(0)}{n!} z^n,[/latex] where [latex]z = x + i y \in \mathbb{C}[/latex] … Continue reading

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Free-Fall Spinning Tunnels

Jump into an evacuated hole drilled straight through a uniform, static Earth-like sphere. Accelerate to 7.9 km/s (or 18 000 m.p.h.) at the center, then decelerate back to zero at the antipodes 42 minutes later! Step out of the hole upside … Conti… Continue reading

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