Black and White

immunity chess puzzle

Black is clearly lost. But there are two squares on which his king can never be checkmated, even if White is allowed to make consecutive moves and checks are ignored. What are they?

Click for Answer

The Persian Princess

In October 2000, a mummy was offered for sale on the black antiquities market in Pakistani Baluchistan. Tribal leader Wali Mohammed Reeki claimed that it had been found after an earthquake near Quetta.

At first a Pakistani archaeologist suggested that the mummy had been a princess of ancient Egypt, or perhaps a daughter of Persian king Cyrus II. Iran and Pakistan began to contend for its ownership, but then American archaeologist Oscar White Muscarella came forward to say he’d been offered a similarly uncertified mummy the previous March which had turned out to be a forgery.

On examination, the “Persian Princess” turned out to be substantially younger than her coffin — in fact, the mat under her body was only 5 years old.

In the end, Asma Ibrahim, curator of the National Museum of Pakistan, reported that the woman had in fact died only around 1996, possibly even murdered to provide a corpse. She was eventually interred with proper burial rites, but her identity remains unknown.

Podcast Episode 315: Beryl Markham’s Unconventional Life

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Beryl Markham managed to fit three extraordinary careers into one lifetime: She was a champion racehorse trainer, a pioneering bush pilot, and a best-selling author. In this week’s episode of the Futility Closet podcast we’ll review her eventful life, including her historic solo flight across the Atlantic in 1936.

We’ll also portray some Canadian snakes and puzzle over a deadly car.

See full show notes …

Watch Your Step

In 2016, Manchester’s Casa Ceramic installed custom tiles in its entry corridor to create the illusion of an uneven surface.

Sales administrator Harry Molyneaux says the effect is most vivid in photographs.

“The floor is completely flat and safe to walk over.”

Miss and Hit

At the commencement of this battle [Gettysburg], as the Regiment was rushing forward toward the enemy, a cannon ball passed between the legs of Captain Robert Story, of Company B, plowing up the earth beyond, yet he rushed on until, half an hour later, he lay mortally wounded, in the enemy’s lines. He was struck in the left thigh by a Minnie ball, which, on reaching and fracturing the bone, divided into three parts.

— Abram P. Smith, History of the Seventy-Sixth Regiment New York Volunteers, 1867

Throwing a Curve

In 2009, mathematician Jeff Chyatte and his colleagues at Maryland’s Montgomery College built a mathematical sculpture: An inclined rod is connected at its center to a horizontal arm, which is connected to a rotating vertical axis. As the axis rotates, the rod passes through a vertical plane.

What shape does the rod cut in the plane? Perhaps surprisingly, it’s a hyperbola. See the video above for an explanation. Chyatte’s sculpture was displayed at Washington’s Touchstone Gallery with the title “Theorem.”

(“Just Passing Through,” Math Horizons 16:4 [April 2009], 16.)

Local Rules

A footnote from T.W. Körner’s The Pleasures of Counting:

It may help to recall the bon mot I heard from a Russian physicist: ‘Proofs in physics follow the standards of British justice and hold the accused innocent until proved guilty. Proofs in mathematics follow the standards of Stalinist justice and hold the accused guilty until proved innocent.’

Figure and Ground

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Image: Wikimedia Commons

A recipe for “toast sandwiches,” from Mrs. Beeton’s Dictionary of Every-Day Cookery, 1865:

Ingredients. — Thin cold toast, thin slices of bread-and-butter, pepper and salt to taste. Mode. — Place a very thin piece of cold toast between 2 slices of thin bread-and-butter in the form of a sandwich, adding a seasoning of pepper and salt. This sandwich may be varied by adding a little pulled meat, or very fine slices of cold meat, to the toast, and in any of these forms will be found very tempting to the appetite of an invalid.

In 2011 the Royal Society of Chemistry worked out the nutritional content:

3 slices of white bread = 240 Calories. Butter = 10 g = 90 Calories
Total = 330 Calories
Toast sandwich nutrients
Protein = 9.5 g
Fat = 12 g
Carbohydrate = 55 g
Fibre = 4.5 grams
Calcium = 120 mg
Iron = 2 mg
Vitamin A = 90 mcg
Vitamin B1 = 0.25 mg
Vitamin B2 = 80 mcg
Vitamin B3 = 4 mg
Vitamin D = 0.08 mcg

“I’ve tried it and it’s surprisingly nice to eat and quite filling,” said he RSC’s John Emsley. “I would emphasise that toast sandwiches are also good at saving you calories as well as money, provided you only have one toast sandwich for lunch and nothing else.”

Experiment

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From Enrico Fermi’s eyewitness report on the first detonation of a nuclear device, July 16, 1945:

About 40 seconds after the explosion, the air blast reached me. I tried to estimate its strength by dropping from about six feet small pieces of paper before, during, and after the passage of the blast wave. Since, at the time, there was no wind I could observe very distinctly and actually measure the displacement of the pieces of paper that were in the process of falling while the blast was passing. The shift was about 2½ meters, which, at the time, I estimated to correspond to the blast that would be produced by ten thousand tons of T.N.T.

Radiochemical analysis of soil samples later indicated that the total yield had been around 18.6 kilotons of TNT.

10/09/2020 UPDATE: Here’s Fermi’s report. (Thanks, Sivaraam.)