Putting Slippers On for That Morning Commute

Old Transportation Challenge

Starting from scratch, what would be the best transportation system of the future for getting everybody to work?


Mark Thompson describes trains that do not waste any time stopping at stations. The last little car on the train separates itself, stops, exchanges passengers, and then accelerates to be joined to the front of the next train through the station.

Eric Klieber has an idea for luring car drivers back to public transportation: "There's only one thing Americans love as much as cars, and that's TV. [Put] TVs in every bus and rapid transit car; TVs in every waiting area; even TVs moving in sync with escalators and moving sidewalks." Everyone could wear radio headphones. TV networks could pay for the whole thing.

Adam Snow (similarly Michael Jackson) may have the best transportation system of the future - slippers: "Since the ideal job of the future would allow one to telecommute, the ideal transit system from bedroom to computer terminal would be a comfortable pair of slippers," he says.

John Robertson, looking farther ahead, proposes instant teleportation (as on "Star Trek"), and having robots do the work, so we can spend our time doing mathematics.

Origin of number symbols

We received two marvelous explanations of the origin of our number symbols. Louis Hansell describes how perfectly the symbols model hand signals for numbers. For example, three horizontal fingers look like the symbol 3; a clenched fist plus a thumb up look like the symbol 6.

Calvin Senning (similarly Duncan Charters) sends a 30-year-old clipping from Reader's Digest which says that a thousand years ago a Moroccan genius designed the symbols to have the appropriate number of angles, like those submitted by Michael Marcotty in Math Chat of July 9.

New weather records challenge (Michael Marcotty)

This July was the warmest ever recorded. What is the probability of that happening by chance as opposed to a longterm weather trend?

* Send answers and new questions to:

Math Chat

Math Department, Williams College

Williamstown, MA 01267

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