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# Strange but true: 'Prolate spheroid' shapes football game

Question: The game sure would be different if played with a plain old spheroid instead of a "prolate spheroid." How so? And where does "specular reflection" fit into it?

Answer: That's the shape of a football, and as you fans well know, its pointy elongatedness renders it easier to throw than if it were a simple sphere, says Timothy Gay in "Football Physics: The Science of the Game." (A true prolate spheroid has more rounded ends, but a football is close.) Because of its shape, the ball is easier to carry, tucked between arm and rib cage to make fumbling less likely. "Finally, the football's unique shape gives it an exceptionally erratic bounce that has unpredictable consequences over the course of the game."

Specular reflection is what a laser beam does when it bounces off a mirror — its angle coming in equals its angle going out, close to the way a soccer ball bounces. However, a football will have none of this sort of predictability.

For punt and kickoff returners, this means the ball may land at their feet and proceed to bounce out of their grasp.

Some fumble-itis victims are even asked by coaches to carry the football with them all week, but a better bet, says Gay, is to keep a low center of body mass and hold the ball four- point style: Vectors, torques and techniques triumphing amid all the black-and-blue.

Question: Imagine you've established radio communication with Alphor, a being on Beton in a distant planetary system. How can you tell him your age, height and weight?

Answer: Our years, months and days are of course Earth and Moon units, so our conventional units of time probably wouldn't help. Ditto our units of distance and force.

What to do? Remarkably there exists a fundamental system of units that would be known by any technological society comparable to ours, the so-called Planck units in honor of the physicist Max Planck. These are based on three cosmically universal constants: the speed of light, Newton's gravitational constant, and Planck's constant.

Planck noticed that any given amount of time (such as your age) when divided by a particular combination of the constants yields a pure number — a number without units! The same trick works with length (height), force (weight) and, indeed, any physical quantity.

Thus you could report your age, height and weight to Alphor as pure numbers, without Earthling bias, and the brainy guy on Beton could "decode" the numbers reported into whatever units are used there. So why don't we abandon our Earthly parochialism and adopt these "natural" units? One clue: your Planck age is more than 50 digits long!

Question:Can a 70-year-old woman have a baby? May be coming someday to a fertility clinic near you.

Answer: In 2005, a healthy baby girl was born in a New York hospital, conceived with an egg that had been frozen and thawed, only 1 of about 125 children in the world born from frozen eggs, says Judith Newman in "Discover" magazine.

Until recently it was difficult to thaw unfertilized frozen eggs without destroying them. But New York University reproductive endocrinologist Jamie Grifo and his associate have now frozen and unfrozen the eggs of several women, with positive pregnancy test results comparable to what is seen with in-vitro fertilization.

Now a woman can theoretically freeze her eggs when young, then have her own genetic offspring when she is . . . 50, 60, or even older, says Newman. There are of course ethical quandaries, such as a 60-year-old having a newborn who could easily be motherless by age 15. But the technology could prove a godsend for cancer survivors, who can freeze their eggs before treatment damages their ovaries. By one method, eggs are plunged into liquid nitrogen and cooled at a rate of 36,000 degrees F per minute to 385 degrees F below zero. The thawed eggs have a survival rate of about 90 percent.

"It's too soon to tell if lots of women will actually end up using egg-freezing to delay having families," says Dr. Grifo. "At least it gives them the possibility."

Send STRANGE questions to brothers Bill and Rich at strangetrue@compuserve.com.