Science Frontiers ONLINE No. 86: Mar-Apr 1993Issue Contents

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"Start with any number that is a string of digits -- , say, 9 288 759 -- and count the number of even digits, the number of odd digits, and the total number of digits it contains. These are 3 (three evens), 4 (four odds), and 7 (seven is the total number of digits), respectively. Use these digits to form the next string or number, 347. If you repeat the process with 347, you get 1, 2, 3. If you repeat with 123, you get 123 again. The number 123, with respect to this process and universe of numbers, is a mathematical black hole."

We have a black hole because we cannot escape, just as spaceships are doomed when captured by a physical black hole! You end up with 123 regardless of the number you start with. Other sorts of mathematical black holes exist, such as the Collatz Conjecture, but we must not fall into them because our printer awaits.

(Ecker, Michael; "Caution: Black Holes at Work," New Scientist, p. 38, December 19/26, 1992.)

From Science Frontiers #86, MAR-APR 1993. © 1993-2000 William R. Corliss

Science Frontiers Sourcebook Project Reviewed in:

Quotes

 "A sourcebook of unexplained phenomena is therefore a valuable addition to a collection of scientific literature. William R. Corliss has provided this in the past with his source books of scientific anomalies in several subjects, and now he has provided it for astronomy. He has done an excellent job of collecting and editing a large amount of material, taken in part from scientific journals and in part from scientific reporting in the popular or semi-scientific press." -- "The Mysterious Universe: A Handbook of Astronomical Anomalies", reviwed by Thomas Gold, Cornell University, in Icarus, vol.41, 1980 "An interesting, systematic presentation of unusual weather [..] This book is recommended for a general audience" --"Corliss, William R., Tornados, Dark Days, Anomalous Precipitation, and Related Weather Phenomena, Sourcebook Project, 1983.", revieweed in Choice, September 1983 "..the science is necessarily somewhat speculative, but Corliss's symthesis is based on reputable sources." -- "Corliss, William R. (Compiler). Lightning, Auroras, Nocturnal Lights, and Related Luminous Phenomena" reviwed by Joseph M. Moran, Univ. of Wisconsin in Science Books and Films, Sep/Oct 1983 "Before opening the book, I set certain standards that a volume which treads into dangerous grounds grounds like this must meet. The author scrupulously met, or even exceeded those standards. Each phenomenon is exhaustively documented, with references to scientific journals [..] and extensive quotations" -- "Book Review: The moon and planets: a catalog of astronomical anomalies", The Sourcebook Project, 1985., Corliss, W. R., Journal of the Royal Astronomical Society of Canada, Vol. 81, no. 1 (1987), p. 24., 02/1987