The Millennium Problems: The Seven Greatest Unsolved Mathematical Puzzles of Our Time [Englisch] [Gebundene Ausgabe]

To help you evaluate my evaluation, let me note up front that I have three long-ago years of graduate math courses under my belt, which made me familiar with four of the seven problems discussed here. I got bored with much of the account of those four, had fun with the discussion of the sixth problem (the Birch and Swinnerton-Dyer Conjecture, which has to do with rational points on elliptic curves), and obtained a vague picture of the remaining two.

My three-star rating is bound to be misleading. Keith Devlin has an enormous gift for mathematical explanation, but as he himself recognizes, in attempting to explain to the proverbial man on the street the seven Millenium Problems (for solving each of which the Clay Mathematical Institute, hoping to spur mathematical research in the 21st century somewhat as David Hilbert did with his famous set of 23 problems in the century just past, has put up a cool million American dollars), he has bitten off more than anyone could possibly chew. I don't mean to suggest it could have been done any better.

If you hanker to tackle the problems and win one of those millions for yourself, start hankering for some other pipe dream. These problems are tough. If you want to thoroughly understand what they consist of, you will need to go to the official technical description of the problems in the book jointly prepared by the Clay institute and the American Mathematical Society. If you want a light overview of them, there's no such thing, but this book is as good a compromise between ease and clarity as you will get. If you just want a feel for where mathematics in general stands at this point in history, the backward glance at Hilbert's problems given in "The Honors Class" is a better place to start.

The challenge for Devlin (aside from gearing up to understand the two most abstruse problems himself) was to describe the problems without assuming any knowledge on the reader's part beyond high school algebra. So he has a humongous amount of ground to cover. With sprightly historical notes, he zips through complex numbers, complex functions, infinite sums and products, special relativity, quantum field theory, symmetry groups - and that's just the first two, easiest chapters. He does a particularly fine job, I felt, with the fifth chapter, on Poincare's conjecture. The mathematics needed for a precise statement of the conjecture is fairly daunting, but his informal description conveys the heart of it vividly and accurately.

All the above is subject to a major caveat. The real agenda for this volume is narrower than educating the general public. The main thing the Clay Institute wanted its prize offer to accomplish was to stir interest in math among students. Considered in those terms, I'd give it five stars, because the people who are going to lap the book up with relish are mathematically gifted high school students. If bits of each chapter go over their heads, it will only serve to whet their appetites. Because it's so ideally suited for them, I'd like to see (and I'm sure the Clay Institute would like to see) Devlin's opus in every high school library in the country.

One can of course think of many other problems that fit the stature of the millennium problems, such as the invariant subspace conjecture, or developing a complete mathematical model of the cell, but these seven will no doubt spark the curiosity of a few young persons as they further their studies in mathematics. Some of the millennium problems, such as the Riemann hypothesis, the NP problem, the Poincare conjecture, and the Navier-Stokes equations, require only an undergraduate education. The others definitely require more background, just to understand even the statement of the problem. All of the them are fascinating, and will no doubt stimulate some incredibly interesting mathematical constructions.

Personal note for anyone interested (from someone who has worked on one of these problems for several years): For those readers who are thinking about attacking one of these problems, it is important to be really interested in solving it, for your own satisfaction, and not to be concerned about the financial reward or what the solution will bring you in terms of professional advancement. Large blocks of time will be needed to think about the problem, and therefore you will have to be concerned with your livelihood in the interim. Being a single person will definitely relieve you of the financial burden of having to support a family, but on the other hand a family will bring you personal warmth as you take the roller coaster ride of confidence and depression that goes with this kind of research. A traditional tenure-track position might be difficult to justify, since you will not be publishing and therefore your chances of obtaining tenure will be greatly diminished. It might also be wise in whatever job you work in to keep your ambitions to yourself, as colleagues and other mathematicians will typically not be encouraging in your decision to work on the problem. Therefore, you will definitely find yourself working on two problems in your life: the millennium problem and a constrained optimization problem, the latter being how to live your life in the interim, and whose solution possibly ranks in similar complexity. Your research in the millennium problem will probably take years, and as you see more lines appear on your face and your colleagues take the normal professional route, you might have doubts about your decisions. The more time spent on it without resolution of course will close the doors on a standard career in academia, and you will approach a critical point where there is no turning back. It is at this time that you will realize that it is you that has taken charge of yourself, your goals, and your attitudes about mathematics and life...and this of course is the best possible life anyone can have.

· The Riemann hypothesis
· Yang-Mills Theory and the Mass Gap Hypothesis
· The P vs. NP Problem
· The Navier-Stokes Equations
· The Poincare Conjecture
· The Birch and Swinnerton-Dyer Conjecture
· The Hodge Conjecture

and the Riemann hypothesis is distinguished in that it is the only one that was also on Hilbert's list at the turn of the previous century. In his descriptions of the last two problems, it is clear that Devlin is struggling to understand the fundamentals of the problems.
Nevertheless, he does manage to inform the reader about what the problems are about, as well as a taste of how difficult they are. Like the problems David Hilbert stated in 1900, this collection of problems forms a marker by which the mathematical progress of this century will be measured. For that reason, all mathematicians should learn something about them, and this book is an ideal initial step.

Published in Recreational Mathematics e-mail newsletter, reprinted with permission.