I am a retired high school mathematics teacher who has quilted mathematical ideas for over 20 years. Currently, I am working on a quilt called Pascal's Pumpkin. I was totally excited by "Swirling Seas, Crystal Balls: Spirals of triangles crinkle into intricate structures" (SN: 10/21/06, p. 266) and began to think about quilting some spidrons!
West Lafayette, Ind.
Check the record
The research showing that experimental animals receiving both antibiotics and stomach-acid suppressants colonized large numbers of drug-resistant intestinal bacteria ("Do acid blockers let microbes reach the colon?" SN: 10/21/06, p. 269) might be important to preventing drug-resistant Clostridium difficile. Reviewing patients' records to see whether those who developed the disease were more frequently prescribed antibiotics and stomach-acid blockers at the same time might be helpful in preventing this serious problem for patients in hospitals and nursing homes.
They're at it again
An entire scientific community could be wrong about something, be expected to know that they are wrong, and for nearly inexplicable reasons persist in being wrong ("Fit to Be Tied: Impatience with string theory boils over," SN: 10/21/06, p. 264). This happened when the medical establishment embraced Freudian psychology as an explanation of human behavior. In spite of extensive training in the biological and chemical sciences, medical practitioners of Freudian psychoanalysis ignored the basic principle that any scientific explanation of natural phenomena, including human behavior, must be testable. Perhaps physicist-author Lee Smolin is right in suggesting we are witnessing groupthink, again.
Bill Van Sickle
"Assault on Andromeda: Nearby galaxy had recent collision" (SN: 10/21/06, p. 261) states, "Several billion years from now, scientists predict, the galaxy and the Milky Way will collide...." How can galactic collisions occur in an expanding universe, where galaxies should be moving away from each other?
On the large scale, objects are indeed receding from each other. But locally, the gravity of two large galaxies that are relatively near overcomes cosmic expansion.—R. Cowen