# Search - List of Books by Florin Diacu

**Florin Diacu** (born Sibiu, Romania, 1959) is a Canadian mathematician and author.

He graduated with a Diploma in Mathematics from the University of Bucharest in 1983. Between 1983 and 1988 he worked as a math teacher in Media?. In 1989 he obtained his doctoral degree at the University of Heidelberg in Germany with a thesis in celestial mechanics. After a visiting position at the University of Dortmund, he emigrated to Canada, where he became a post-doctoral fellow at Centre de Recherches Mathématiques (CRM) in Montréal. Since 1991, he has been a professor at the University of Victoria in British Columbia, where he was the director of the Pacific Institute for the Mathematical Sciences (PIMS) between 1999 and 2003. He also held short-term visiting positions at the Victoria University of Wellington, New Zealand (1993), University of Bucharest, Romania (1998), University of Pernambuco in Recife, Brazil (1999), and The Bernoulli Institute (at EPFL) in Lausanne, Switzerland (2004). He was invited to speak and lecture all over the world.

Diacu's research is focused on qualitative aspects of the n-body problem of celestial mechanics.In the early 1990s he proposed the study of Manev's gravitational law, given by a small perturbationof Newton's law, in the general context of (what he called) quasihomogeneous potentials. In several papers, written alone or in collaboration, he showed that Manev's law, which provides a classical explanation of the perihelion advance of Mercury, is a bordering case between two large classes of attraction laws. Several expertsfollowed this research direction, in which more than 100 papers have been published to this day.

Diacu's more recent research interest regards the n-body problem in spaces of constant curvature.For the case n=2, this problem was independently proposed by Bolyai and Lobachevsky, the founders of hyperbolic geometry. But though many papers were written on this subject, the equations of motionfor any number, n, of bodies were obtained only in 2008.These equations provided him with a new criterion for determining the geometrical natureof the physical space. More specifically, he showed that celestial orbits depend on the curvatureof the space. For instance, the Lagrangian orbits (when three bodies are at the vertices of arotating equilateral triangle) can have bodies of any mass in the Euclidean (flat) space, butthe masses must be equal if the space has negative or positive curvature. Since Lagrangianorbits of non-equal masses exist in our solar system (Sun, Jupiter, and the Trojan asteroids),we can conclude that, if assumed to have constant curvature, the physical space is Euclideanfor distances comparable to those of our solar system.

Diacu also obtained some important results on Saari's conjecture, which states that every solution of the n-body problem with constant moment of inertia is a relative equilibrium.

Apart from his mathematics research, Florin Diacu is also an author of several successful books. He wrote a monograph about celestial mechanics and a textbook of differential equations. Lately he became interested in conveying complex scientific and scholarly ideas to the general public. His most successful books in this sense are:

*Celestial Encounters: The Origins of Chaos and Stability*, co-authored with Philip Holmes, Princeton University Press (1996), (ISBN 0-691-00545-1). It received the *Best Academic Book Award of 1997* from "The American Reporter Book Review", and was translated into Chinese, Greek, Hungarian, Japanese, Romanian, and Russian. This book is a history of ideas tracing the birth and development of chaos theory.
*The Lost Millennium: History's Timetables Under Siege*, Knopf Canada (2005) (ISBN 0-676-97657-3), is a treatment of the problems of historical chronology. The author discusses how historical events were dated and presents the objections brought to the traditional approach by scientists like Isaac Newton and mathematicians such as Anatoly Fomenko. A modified Romanian version appeared in 2009.
*Megadisasters: The Science of Predicting the Next Catastrophe*, Princeton University Press (2009) (ISBN 0-691-13350-6) and Oxford University Press (2009) (ISBN 978-0-19-923778-4), traces the history of the scientific efforts made to predict and minimize the damage resulting from major catastrophes, such as tsunamis, earthquakes, volcanic eruptions, rapid climate change, hurricanes, collisions with asteroids or comets, stock-market crashes, and pandemics.

**Total Books:** 8