Research area: Algorithmic Combinatorics
| Email: | gill.williamson@gmail.com |
Geology Manifold - Missing Geology: Charts of regional geology in context of earth's history -- formations present, formations absent
Botany Manifold - Terminology: Charts of regional plant families showing terminology and relationships (site under development)
Fiction: The Observers
In Jurassic time, when dinosaurs reigned supreme, an alien civilization of microrobotic natural historians arrived on earth. Unnoticed, they have recorded the earth's history in magnificent detail. They have observed without interfering.
But government engineers in Arizona have invented something new and dangerous. The alien observers must finally introduce themselves to the human race.
Matthew Crigler, a young geophysicist, is the first person to meet the Observers. He becomes a reluctant advisor to the aliens and their plans for a gentle introduction. No amount of advice can save the human race from the chaos that ensues.
The publisher of The Observers is iUniverse (ISBN 978-0-595-39478-4). An E-Book version is available at the publisher's site. At present, Barnes & Noble has the new edition and also has a "see inside" feature. The Kindle Edition is available through Amazon. Warning: Some readers have purchased the new version (ISBN 978-0-595-39478-4) on Amazon but have been shipped the old version. If you enter "s gill williamson observers" in Google you will get some additional links to the book.
Comments on The Observers by Vernor Vinge
Author's Notes: Reader's Questions and Comments
ARE THE OBSERVERS FOR REAL? Far from being unlikely, the existence of such a civilization is a natural consequence of the laws of computer science. The Drake equation L-value of the Observers is essentially infinite, with signals theoretically detectable but far below the threshold of SETI detectors. The most advanced such robotic civilizations are probably recording and studying the history of the universe -- a challenge uniquely complex enough to force them to continue to evolve as societies. Within a few hundred years we will be able to create our own version of the Observers, but, as our story indicates, such an act may carry great risks! As the universe ages and expands, civilizations of intelligent biologically-evolved beings will become more isolated in space-time. Their only hope of learning about the early development of our universe may be from contacts with robotic guardians of history such as the Observers.
A Recent Lower Division Undergraduate Text:
Professor Ed Bender (Department of Mathematics, UCSD) and I have written an introductory textbook which covers the material in the lower division Computer Science and Engineering discrete mathematics course (CSE 20) at UCSD. Hundreds of students used this text during its development and gave us their feedback. Dover Publications, Inc. is the publisher.
A Short Course in Discrete Mathematics
A HELPFUL HINT FOR STUDYING THIS MATERIAL: At the end of each unit of study you will find a collection of multiple choice questions (Multiple Choice Questions for Review). Read these questions before reading the corresponding unit. Try to work the questions by (1) reading each question and (2) looking back through the unit to dig up just what you need to answer that particular question. Make a game of it: just learn the minimum needed to understand and work each multiple choice question. When you learn to work all of the multiple choice questions (answers are given), then go through the corresponding unit systematically.
A Recent Upper Division Undergraduate/Graduate Text:
Foundations of Combinatorics with Applications
This book, written with my colleague Ed Bender, has been published (2006) by Dover Publications, Inc. The list price is $22.95. This book has four parts. Parts I and II are suitable for an upper division undergraduate course. Part III is slightly more advanced. Part IV is much more advanced. Parts I, II, and III (selections) have regularly been taught to advanced undergraduates in mathematics at UCSD.
An Unusual Graduate Text:
Combinatorics for Computer Science
The above link is to the version published (2002) by Dover Publications, Inc. (originally published in 1985 by Computer Science Press). The list price is $22.95.
The unusual thing about this book is that it is a record of student participation in a graduate mathematics course taught by me in algorithmic combinatorics from 1978 to 1985. The Table of Contents is replaced by a Study Guide for each of the ten chapters. Each item in the Study Guide that is in capital letters, for example CODING DOMINO COVERINGS, was a topic presented in class at the blackboard by a graduate student in the Department of Mathematics at UCSD (where I was a professor from 1965 to 1991). Both master's and doctoral students participated. Over the years, we developed an approach to explaining and presenting this material that was due to the students themselves.
Being student-developed, this book has a unique style -- rich in examples with the proofs closely tied to the examples. There are many useful ideas for anyone attempting to program problems of a combinatorial nature. The various chapters, after the first, are largely independent.
Data Structure Properties Not Provable With Math (ZFC)?