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Reviews of Relevant Books
Steven Stogatz is currently a mathematics professor at Cornell University. He studied at Princeton and Cambridge and received his PhD from Harvard. He also spent five years teaching mathematics at MIT. In addition to teaching for more than twenty years, he has been studying the role that sync plays in subjects such as human sleep cycles, three dimensional chemical waves, biological oscillators and fireflies. His book Sync is the story of his personal journey from grad school up until the time that he wrote the book detailing many of the intriguing discoveries he and others have made. What makes the book enjoyable to read is not only the wide range of intriguing subjects that he covers, but also the engaging and sometimes humorous stories about the people that have influenced his life. These people are his teachers, colleagues, students and other scientists who are all exploring what seems to be emerging as a common thread throughout the universe. This thread is sync and it can be found almost anywhere one takes the time to look. It is in fireflies in the jungles of Thailand, the beating of the human heart, power grids, lasers and superconductors.
One drawback to the book is that some of the topics that he covers involve complex mathematical and technical explanations that can be difficult if not impossible for someone without the appropriate background to understand. However most of the time, Strogratz takes the time to explain fundamental processes and does it with such simplicity that it enables someone without prior knowledge to understand the majority of the subjects he covers. For example, one of the topics that he goes into a fair bit of detail explaining is oscillation. Oscillation is at the heart of many synchronous systems and he uses the simple image of flushing toilets to provide an articulate explanation of how the process works. Strogatz uses fireflies not only as an example of oscillators that synchronize but also to point out of the importance that sync has in other applications.
Fireflies are a perfect example of oscillation and they have been the subject of a great deal of study. In the jungles of Thailand flashing fireflies are able to spontaneously synchronize. It was though that this was the only place on earth this was happening until a woman in Tennessee reported that she had witnessed the same thing happening there as well. When it was announced that the government was spending tax money to study the synchronous behavior in fireflies, one Representative from Wisconsin was outraged. However, Strogatz points out that understanding the principles of sync has allowed engineers to identify and solve traffic jams on the internet, and firefly enzymes are being used in the testing of drugs to treat tuberculosis.
Strogatz was first introduced to sync while he was studying at Cambridge in 1981. He felt he was lacking a clear direction that his career should take and was looking for some inspiration in a local book store. He came across a book with a title remarkably similar to the subject of his own thesis paper, and was intrigued by the originality of the authors' ideas. The author was Arthur Winfree and he was to become Strogatz's teacher, mentor and friend.
Strogatz wrote to Winfree and began working with him that summer. His first project was to study the behavior of oscillators in a three dimensional environment. Up until this time they had only been studied in regard to one dimension, time. But in reality these systems do not operate in a single dimension. The problem in attempting to perform these studies was the mathematics involved were extremely complex and computing capacity at the time was still relatively low. This was coupled with the fact that they were unsure of how to interpret any results of these calculations.
Instead of using his Steven's mathematical background, Winfree put him to work studying Zhabotinsky soup. It sounds like something invented for a science fiction novel, but it was developed in the 1950's by two Russian scientists. The remarkable thing about these chemicals was that they were capable of spontaneously creating waves similar to those that cause the human heart to beat. With the aid of this soup, Strogatz was able to model the activity of oscillators in a three dimensional environment. In more recent years these same methods have enabled scientists to discover another type of wave that may help explain the reason behind sudden cardiac deaths.
Sync is involved in almost every system in the human body. Pacemaker cells in the heart all oscillate, and it is their synchronization that causes the heart to beat. Oscillating cells in the intestine synchronize into a rhythm that aids in digestion. The body's circadian rhythm is thought to be linked to pacemaker cells which control our sleep patterns. Scientists are studying the synchronous qualities of neural activity hoping to be able to gain a better understanding of how we are able to learn, are able to recognize odors and how memories are formed.
All of these systems of oscillators function sympathetically with respect to their geographic location are self organized networks. They bear striking resemblance to more complex networks that we are only beginning to comprehend. Massive power grids and the Web are examples of gigantic networks that have evolved without an organizer responsible for the overall design, yet they display the same spontaneous organization of the synchronizing oscillating systems seen in the flashing of fire flies and Zhabotinsky soup. This so called ripple effect is what enabled just two failed power lines to disrupt power to over 7 million people in 1996, the Love Bug worm to cause billions of dollars of damage world wide.
The effect of sync also shows up in other surprising places. The Millennium Bridge in London which linked St. Paul's Cathedral with the Tate Museum opened in June of 2000. It was a radical new design of the suspension bridge. On opening day, once the ribbon was cut, the public streamed onto the bridge. It suddenly began to vibrate and sway from side to side, sometimes deviating up to 20 centimeters from its origin. Engineers tried in vain to discover what miscalculation they had made and the bridge was closed just two days later. It was later discovered that the synchronous foot steps of the people crossing the bridge that caused the effect. This was surprising for two reasons. One was the obviously unpredicted effect that the crowd walking across the bridge would have its movement, the other is that 2000 people unprompted in any way, somehow managed to move into perfect sync.
The role that sync plays in so many diverse systems in the universe is prompting people like Strogatz to study science in a whole new way. One can sense in this book the enthusiasm that Strogatz has for the work that he is involved with. He believes that a new era in scientific research is emerging that may lead to the discovery of the secret of the universe.