All Stories by Ivars Peterson
- Math
Whips and Dinosaur Tails
The loud crack of a deftly flicked bullwhip can certainly command attention. That distinctive noise is a small sonic boom, generated when the whip’s thin, highly flexible tip exceeds the speed of sound. Swinging a leather bullwhip’s thick, rigid handle in an arc gives the whip angular momentum. Sharply reversing the motion’s direction sends a […]
- Math
Doing the Wave
It was the first home game of the season for the University of Maryland football team. About 48,000 fans had crowded into Byrd Stadium to watch the Terrapins take on the University of Akron Zips. Inevitably, during a lull in what turned out to be a rather one-sided contest, the assembled spectators created their own […]
- Math
A Fair Deal for Housemates
A triangulated triangle with a proper Sperner labeling and an odd number (3) of elementary triangles possessing all three labels (shown in color). Four friends move into a house and find they must choose among four rooms of different size and quality. Instead of sharing the rent equally, they decide to divide the total so […]
- Math
Great Computations
From sifting through radio telescope signals for signs of extraterrestrial life to searching for record-breaking prime numbers, home and office computers contribute via the Internet to a variety of research efforts.
- Math
Solving an Ancient African Game
The game of awari has entranced players for thousands of years. Originating in Africa, it remains a popular pastime in many parts of the world. Awari and its numerous variants are instances of “count-and-capture” strategy games, and they are known generically as mancala games. In its traditional form, the awari game “board” consists of two […]
- Math
Golden Blossoms, Pi Flowers
In the head of a sunflower, the tiny florets that turn into seeds are typically arranged in two intersecting families of spirals, one winding clockwise and the other winding counterclockwise. Count the number of florets along a spiral and you are likely to find 21, 34, 55, 89, or 144. Indeed, if 34 floret (or […]
- Math
Losing to Win
It’s a gift to born losers. Researchers have demonstrated that two games of chance, each guaranteed to give a player a predominance of losses in the long term, can add up to a winning outcome if the player alternates randomly between the two games. This striking new result in game theory is now called Parrondo’s […]
- Math
Packing spheres around a sphere
A mathematician has proved that the optimal arrangement of 12 identical spheres around and touching a 13th is a highly symmetric pattern based on the 12-faced geometric shape known as the dodecahedron.
- Math
A fair deal for housemates
A new mathematical recipe for fair division allows people to resolve disputes over the splitting up of rent, goods, or even burdensome chores.
- Math
Math Prizes: Honors for connecting number theory, geometry, and algebra
Fields Medals were awarded to two mathematicians, Laurent Lafforgue and Vladimir Voevodsky, who forged new links between different branches of mathematics.
- Math
Probabilities in Bingo
One of the little pleasures of our annual winter vacation is an evening Bingo party. After a day of sledding and cross-country skiing, it’s relaxing to indulge in a social game that requires minimal thought, affords young and old the same chance of winning, and has a strong element of suspense. To play Bingo, each […]
- Math
Troublesome Weather Trends
Unlike the day or year, the week isn’t tied to any naturally recurring phenomenon. When meteorologists detect a trend that follows a weekly rhythm, they suspect that human activities–and the 5-day work week–are responsible. In 1998, researchers at Arizona State University in Tempe reported that daily oceanic rainfall shows a weekly precipitation cycle across a […]
