*Gamma*is a gold mine of irresistible mathematical nuggets. Anyone with a serious interest in maths will find it richly rewarding."

**--Ben Longstaff,**

*New Scientist*Exploring Euler's Constant

With a foreword by Freeman Dyson

Editions

Among the many constants that appear in mathematics, *π*, *e*, and *i* are the most familiar. Following closely behind is *y*, or gamma, a constant that arises in many mathematical areas yet maintains a profound sense of mystery.

In a tantalizing blend of history and mathematics, Julian Havil takes the reader on a journey through logarithms and the harmonic series, the two defining elements of gamma, toward the first account of gamma's place in mathematics.

Introduced by the Swiss mathematician Leonhard Euler (1707-1783), who figures prominently in this book, gamma is defined as the limit of the sum of 1 + 1/2 + 1/3 + . . . Up to 1/*n*, minus the natural logarithm of *n*--the numerical value being 0.5772156. . . . But unlike its more celebrated colleagues *π* and *e*, the exact nature of gamma remains a mystery--we don't even know if gamma can be expressed as a fraction.

Among the numerous topics that arise during this historical odyssey into fundamental mathematical ideas are the Prime Number Theorem and the most important open problem in mathematics today--the Riemann Hypothesis (though no proof of either is offered!).

Sure to be popular with not only students and instructors but all math aficionados, *Gamma* takes us through countries, centuries, lives, and works, unfolding along the way the stories of some remarkable mathematics from some remarkable mathematicians.

**Julian Havil** is a retired former master at Winchester College, England, where he taught mathematics for thirty-three years. He received a Ph.D. in mathematics from Oxford University. **Freeman Dyson** is professor emeritus of physics at the Institute for Advanced Study in Princeton. He is the author of several books, including *Disturbing the Universe* and *Origins of Life*.