Numeric Nonsense

Fraser’s Spiral

The Fraser’s spiral illusion is an optical illusion that was first described by the British psychologist Sir James Fraser. The illusion is also known as the false spiral or by its original name, the twisted cord illusion. The overlapping black arc segments appear to form a spiral, but the arcs are in fact concentric circles. The visual distortion is produced by combining a regular line pattern (the black circles) with misaligned parts (the differently colored strands). It is like many other visual effects, in which a sequence of tilted elements cause the eye to perceive phantom twists and deviations. The illusion is augmented by the spiral components in the checkered background. It is a unique illusion, where the observer can verify the concentric strands manually. When the strands are colored differently, it becomes obvious to the observer that no spiral is present. So class, take out your Sharpie and outline one of these circles on your screen.

Infinitely many mathematicians walk into a bar. The first says, “I’ll have a beer.” The second says, “I’ll have half a beer.” The third says, “I’ll have a quarter of a beer.” The barman pulls out just two beers. The mathematicians are all like, “That’s all you’re giving us? How drunk do you expect us to get on that?” The bartender says, “Come on guys. Know your limits.”

G.H. Hardy, an Oxford and Cambridge mathematics professor, professed to be an atheist, but in dealing with providence, he bore in mind the possibility that life’s operation might, after all, be manipulated by God, with an understandably low opinion of Hardy. He also considered air travel dangerous. Once, shortly after Hardy had left on an overseas flight, a colleague found a note lying on his desk that read, “I have proven Fermat’s last theorem.” The news spread and by the time Hardy returned home all the world was agog to learn the proof. Hardy had to explain that he had not proved it—the note had been insurance. God, he said, had been forced to bring him back alive to show him up as an imposter.

How many mathematicians does it take to change a light bulb? One: she gives it to three physicists, thus reducing it to a problem that has already been solved.

Find x

Why’d the chicken cross the road? The answer is trivial & is left as an exercise.

Finally, I’ll leave you with Mathgen, an Internet toy that allows you to generate fake scientific papers. It is a program to randomly generate professional-looking mathematics papers, including theorems, proofs, equations, discussion, and references. Try it for yourself! Here is one of mine: Fermat’s Last Theorem, M. Regenaxe, T. Maxwell and V. Fermat. The results look realistic enough. Just don’t hang around so long that you are asked to explain them. 

Eagle Dazes

Water Intake, Skyline and the Mississippi

It was chilly, but we got out. Tis the season—for eagle watching. A polar vortex swept into town, but we still got out and around. Eagle Days was being celebrated on the Chain of Rocks Bridge and really everywhere on the river. We saw three eagles and two eagle nests, confirming that Saint Louis is a great place to raise a family. More importantly, we got to hang out with some other birders and naturalists. We enjoyed their heated tents too.

I’m a sucker for the MSN slide shows that constantly appear on our home page. I especially enjoy their 50 states best of shows. Like what is the best restaurant, hotel or town in each state. It just so happened that that morning’s survey was all about the 50 best bridges. You guessed it, Missouri’s best bridge was the Chain of Rocks, beating out the much older Eads Bridge. Technically now, it’s the Old Chain of Rocks Bridge, the new one is a half mile further north and is part of I-270. Built in 1935, it was how Route 66 crossed the Mississippi River.

It is now a pedestrian bridge. We walked its one-mile length to Illinois. The bridge now seems too narrow to support two lanes of traffic, but cars were smaller back then. I can only imagine the terror of crossing it at night. It was not very well-lit, so as not to blind river barge wheelmen. That plus its distinct mid-span kink, must have made for an interesting crossing. The bridge gets its name from a natural feature in the river, just downstream from the bridge. A chain of rocks spans the river, making it navigable only in high water. In very low water, the river can be crossed via these rocks. A canal now bypasses this feature.

Afterwards, we swung by Winslow’s Home for a late lunch. We ended up closing the place, which wasn’t as hard as you might think. It closed at three. Last time we were here, we were taking Dan to the airport and then we had a show to see later. This time we didn’t want to feel rushed. This was a good thing, because the place was slammed and it took forever to get our food. It was good though, when it finally arrived. Midway through our meal, a sudden snow squall appeared, dropping enough to coat the Prius and all the roads going home. It was about an inch that replaced last weekend’s dump, which had been washed away by Friday’s heavy rain. By closing Winslow (Its name is a send up to the painter Homer Winslow.), we snagged a couple of free donuts that were going to go unsold anyway.

Anne on the Chain of Rocks Bridge


Leveque Dining Set

On last summer’s westward excursion, we stopped for an afternoon in historic Deadwood, South Dakota. After lunching in a saloon, along Main Street’s strip, we explored the more gentile side of town. The Adams Museum delves into the town’s local history, which during its gold rush days featured such luminaries as Wild Bill Hickok and Calamity Jane. In this museum we saw the pictured oak and walnut dining set, which was built in the 1930s by Anthime Leveque. Anne took these photos, because they reminded her of quilt designs.

Anthime Leveque emigrated from Quebec and at fourteen, began to work for the Home Stake Mining Company in nearby Lead, SD. He worked there his entire life. During his last twenty years of employment, he made furniture with a process called marquetry, a technique using small wood pieces to create surface decorations. Most woodwork of this kind uses thin layers of veneer. Leveque’s pieces are a full quarter-inch thick. His most ambitious set consisted of a quarter million pieces. This set of table and chairs includes a mere 4,500 section.