Making sense of the opponent process theory of color vision

Ev’ry heart beats true ’neath the magenta white and blue.

Here’s an innocuous scientific controversy. I’ve collected a number of these, imagining that maybe they could serve as practice material for making sense of ambiguity outside one’s areas of expertise. I’m not sure it’ll do any good, but it’s worth a shot. I’ll outline the issue below, and, if you like, you can try your hand at sorting it out.

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Mars on the desktop

I work with multiple monitors in different resolutions. I also organize projects using a handful of desktop workspaces (for example, in Windows). Distinctive wallpapers can contribute to a valuable sense of place when you do all your work in the same real location, but it can be hard to find a large enough set that’s beautiful, diverse, high-resolution, and suitable for ultrawide, 4K, or portrait-mode monitors.

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Inverse crimes

Mathematician Rainer Kress coined a cute name for an insidious kind of triviality: the inverse crime.

1 D. Colton and R. Kress, Inverse Acoustic and Electromagnetic Scattering Theory, 4th ed. Springer Nature, 2019, p. 179.

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Wave mechanics in periodic media

Photonic Crystals: Molding the Flow of Light is one of my favorite undergraduate-level textbooks. (PDF freely available.)

Below I reproduce its appendix tabulating the comparisons between quantum mechanics and electromagnetism that the authors make throughout the book. If you’re familiar with one but not the other, you might find it interesting. If you want something more technical, try “Notes on the algebraic structure of wave equations” from Steven G. Johnson (one of the textbook authors, as it happens, though better known for other work). Otherwise, it’s relevant to a few subjects where I like to collect concrete, real-world cases for study—pedagogy, extended analogy, what is or isn’t weird about quantum mechanics.

(I also wanted to experiment with typesetting for my new site here.)

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