Category Archives: uncategorized

Midcentury Monuments

Three serious books lie open before me. I had a variety of reasons for checking them out of the library, although they’re all related in one way or another to current goings on here at the Simons Institute: Donald O. … Continue reading

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Sir Roger Penrose’s Toilet Paper

Twenty years ago, Kimberly-Clark, the Kleenex company, introduced a line of toilet paper embossed with the kite-and-dart aperiodic tiling discovered by Roger Penrose. When I first heard about this, I thought: How clever. Because the pattern never repeats, the creases … Continue reading

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Lots of digital cameras come with a default file-naming scheme of IMG_nnnn, where nnnn is a four-digit number assigned sequen­tially, starting with 0001. The four images above are photos I made with four different cameras over a span of more … Continue reading

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Computing with encrypted data

Let’s suppose you are a client of the notorious accounting firm Dewey, Cheetham & Howe. You want them to compute your income tax, but you don’t trust them with the confidential details of your financial life. This impasse seems insurmountable. … Continue reading

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Kepler’s snowflake

The Kepler conjecture—the one about stacking cannonballs or oranges—is now the Hales theorem, though with a cruelly lingering asterisk. Thomas C. Hales announced his proof in 1998, and it was published in 2005 and 2006 (links). But the referees were unable to fully … Continue reading

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