Frank Morgan's Math Chat


October 18, 2001

Space Curving Back

Old Challenge. How could you tell if the universe doubled back on itself?

Answer. Robert McDowell suggests that you could see yourself in the far distance. Of course since people are so small, it's better to look for recurring patterns of galaxies and other huge objects. Indeed, the 2001 Microwave Anisotropy Probe (MAP) satellite is looking for such recurring patterns. One complication is that different copies may appear from different perspectives. Freelance mathematician and MacArthur Foundation "Genius" award winner Jeff Weeks has a computer program for finding such hidden patterns.

New Challenge. What is the ideal size and shape for a TV set?

John Horton Conway's On Numbers and Games, one of my all-time favorite math books, has now been reprinted in a new edition by A. K. Peters. It is both a completely fresh reformulation of the foundations of algebra and analysis, and a landmark treatise on combinatorial game theory. Conway's incomparable originality, richly whimsical but rigorous style, and mathematical brilliance come through on every page. No summary can do this book justice, so I'll just say that everyone who loves mathematics will find it an inexhaustible treasure. The second edition has added a prologue and an epilogue, as well as dozens of improvements, corrections, and new bibliographical references. Joe Shipman, Math Chat staff.

Copyright 2001, Frank Morgan.

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