"Mathematics is the process of turning coffee into theorems" Paul Erdös
This series is supported entirely by private donations.
Wednesdays at 4:00 p.m.

Coffee at 3:45 p.m.

SEPTEMBER 3 THE GOLDEN RATIO  A CONTRARY VIEWPOINT; Clem Falbo, Professor Emeritus of Mathematics, Sonoma State University. This talk discuses several false or insupportable claims made about the "golden ratio," phi. We illustrate that phi is not, in general, the shape of spirals in sea shells, and particularly it is not the shape of the nautilus. We will show that every number R>1, used as a "ratio," shares all of the alleged "special properties" of phi, including subdividing any rectangle into similar rectangles, and appearing as the limit of the ratio of successive terms in some Fibonaccilike recurrence equation. Pizza after Colloquium.
SEPTEMBER 10 THE MATHEMATICS OF SURFING; Richard Werner, Mathematics, Santa Rosa Junior College. I will briefly discuss ocean waves and why they break. The majority of the talk will focus on the balance of forces that allow a surfer to catch and ride a wave. The proofs are heavily dependent on vector calculus, but students who have not had this class will still be able to understand the results. The presentation will include numerous video clips and still photos.
SEPTEMBER 17 DYNAMICS AND GEOMETRY OF MICROSCOPIC STRUCTURES IN PIECEWISE ROTATIONS; Arek Goetz, Professor of Mathematics, San Francisco State University. In this multimedia talk, we will invite the audience to take an exciting tour of fractal structures arising from the action of piecewise rotations. These structures are produced on a computer using rigorous algorithms with roots in basic algebraic number theory. The talk will be accessible to sophomore undergraduate students.
SEPTEMBER 24 GROUP ACTIONS IN NUMBER THEORY; Tyler J. Evans, Professor of Mathematics, Humboldt State University. Students having had a semester course in abstract algebra are exposed to the elegant way in which finite group theory leads to proofs of familiar facts in number theory. In this talk, we will describe two such proofs using the action of a group on a set. The talk will be self contained, and in particular no knowledge of group theory is necessary.
OCTOBER 1 A STATISTICAL ANALYSIS OF THE 2000 FLORIDA ELECTION; Brian Jersky, Professor of Mathematics, Sonoma State University. The controversy over the 2000 Florida election will never be resolved, but statistical analysis can help us examine the evidence and make up our minds about the result. In this talk, we will look at the results of the Presidential election in Florida, using statistical models to clarify the complex issues that arose. The topic of the talk is accessible to all, though some technical details will not be. Pizza after Colloquium.
OCTOBER 8 WHY VS HOW; Paul Zeitz, Professor of Mathematics, University of San Francisco. Many proofs are logically sound, in that each step follows from the previous one, yet the proof as a whole sheds very little light on whatever was proven. We call such proofs Hows, in contrast to Whys, which are proofs that dramatically get to the heart of the matter. This talk will examine some important Whys that are less wellknown than they should be, and also look at some Hows that are begging for a Why.
OCTOBER 15 THE RIEMANN HYPOTHESIS (or WHO WANTS TO BE A MILLIONAIRE?); Eddy Roubal, Student in Mathematics, Sonoma State University. An overview of the Riemann Hypothesis (student accessible). We will explore the significance of the hypothesis  how it ties in to the distribution of primes and the prime number theorem  and the 143year history of attempts to solve it.
OCTOBER 22 NEUROFUZZY SYSTEMS DEFUZZIED; Benjoe Juliano, Professor of Computer Science, California State University Chico. Neurofuzzy systems are used for modeling and control applications. The unification of neural networks and fuzzy models is facilitated by a common framework called adaptive networks. In this talk, fundamental concepts pertinent in the development of fuzzy models known as ANFIS (AdaptiveNetworkbased Fuzzy Inference System) will be discussed. Design methods for ANFIS in both modeling and control applications will also be introduced.
OCTOBER 29 IT'S ONLY NATURAL; Jeff Haag, Professor of Mathematics, Humboldt State University. The natural exponential and logarithmic functions are good friends of ours. They are entertaining and fun to hang around with, and always willing to help if we have problems. But like any friends, we probably don't know them as well as we think. When we gather for this talk, we'll hear lots of stories about these old friends. Some of the stories are alluded to in calculus or more advanced courses, but often the exciting parts are mired in the midst of more mundane material. We'll stick to the juicy parts. We'll come away more familiar with and more appreciative of our old friends, the natural logarithm and exponential functions.
NOVEMBER 5 MATHEMATICS CAREER DAY; SSU Math Alums. What can you do with a degree in Mathematics? For four answers, come to this colloquium (for more, see November 19). Alums who are in the midst of successful careers in high school teaching, computer architecture, university teaching/research, and financial management will talk about their career paths, and share ideas for interested students. There will be plenty of time for questions. Pizza after Colloquium.
NOVEMBER 12 ETHNOMATHEMATICS OF BASIC NUMBER SENSE; Daniel Orey, Professor of Mathematics and Multicultural Education, California State University, Sacramento.Many Americans experience mathematics negatively; corresponding experiences by students in other countries are much less onesided. We will discuss findings from an indepth study of algorithms used by mathematics learners from several countries, including the complex interaction between the languages spoken and the algorithms used that combine to form individual abilities or disabilities in mathematics.
NOVEMBER 19 DON'T WANT TO TEACH...SO WHAT NOW? Lisa Moran, Renee Raabe, & Jodi Raggio, SSU Mathematics Alumnae (class of 2002) share their "real world" experiences in finding jobs outside of the classroom. With degrees in Statistics, Applied and Pure Mathematics, they are currently working in the auditing and actuarial fields. They are here to answer questions such as what is an Actuary? What is the starting salary? What exactly does an Auditor do? Which cities or locations will provide me with the most opportunities? How can I prepare for interviews? What can I expect in the first few years on the job? If you do not want to teach, yet still want to utilize your math degree, this is a great opportunity to get your questions answered and see what your options are. Pizza after Colloquium.
DECEMBER 3 PRACTICAL APPLICATION OF STATISTICS IN SEMICONDUCTOR MANUFACTURING; Samuel Freeman, Ph.D., & Lisa Zavieh, Ph.D., Microwave Technology Center, Agilent Technologies. Statistics play a pivotal role in the design and manufacture of integrated circuits. Come and see how statistics are used in Agilent's manufacturing facility to provide process monitoring, quality control and assurance, and reliability determination.