EINSTEIN IN SYNC: Albert Einstein (1879-1955) was visiting friends in Santa Barbara when this playful photograph was taken on February 6, 1933, shortly after he had accepted the appointment at the Institute for Advanced Study that would bring him to Princeton for the rest of his life. In celebration of his birthday this Friday, Princeton bicyclists are invited to participate in a special ride around Community Park South. (From Images of America: Institute for Advanced Study; Courtesy of the Archives, California Institute of Technology)

What better way to celebrate Einstein’s birthday than on a bicycle demonstrating the scientific phenomenon of synchrony! That’s exactly what the Princeton Pedestrian and Bicycle Advisory Committee (PBAC) have planned for this Friday evening.

The seven member committee comprised of Princeton residents Karen Jezierny, Steve Kruse, Laurie Harmon, David Cohen, Carolyn Sealfon, Anita Jeerage, and Sam Bunting invite bike riders of all ages to show up with helmets and night-time safety lights of course, as required by state law, and take part in a ride around Community Park South.

So much for the bicycles, where does the synchrony come in? Don’t worry, you won’t be asked to pedal in unison. Instead, participants will be fitted with little gadgets that flash and, by means of a radio transceiver, instantly synchronize with one another.

The effect is known as the Kuramoto Model for Japanese physicist Yoshiki Kuramoto, who published a model of coupled oscillators in 1975. But, as PBAC’s Steve Kruse points out, the phenomenon of collective synchronization has an even earlier connection to Princeton. Arthur Winfree, who earned his doctorate in biology at Princeton University, made a theoretical breakthrough in understanding collective synchronization. Mr. Winfree’s findings are published in his book, The Geometry of Biological Time.

One of the most widely known examples of the phenomenon occurs in certain species of fireflies in the Great Smoky Mountains National Park. “But collective synchrony can also emerge in non-living systems,” said Mr. Kruse, adding “and this is where Einstein ambles into the picture,” before going on to describe Einstein’s collaboration with Indian physicist, Satyendra Nath Bose,and their prediction of the Bose-Einstein condensate.

Participants in Friday’s ride may or may not be aware of the science involved. All they need to do to celebrate the wonders of synchrony is to take part in Friday’s group ride on closed paths in Community Park South.

Participation is free and open to all ages. The first 159 riders will have blinking red tail lights attached to their bicycles. As they loop around the park for a distance of at least 3.14 miles, the lights will harmonize.

Sponsored by Princeton University’s Office of Community and Regional Affairs, Princeton’s Pi Day and the municipality of Princeton, the ride will be the third “Kuramoto Model (1000 Fireflies)” community event.

Conceived by Chicago-based artist David Rueter, the first ride took place with 1,000 bicyclists at a dusk-to-dawn summer arts festival in Minneapolis; the second was at the EdgeUP art festival in Chicago.

Besides the fun element, the ride has a series purpose for PBAC, which advises the mayor and Council on ways to make Princeton increasingly safe and suitable for walkers and bikers.

“Because bike-riding commuters often need to ride in the dark, PBAC starting making plans in late 2012 for an event that would highlight night-time bike safety,” said Mr. Kruse. “New Jersey law requires bicycles to be equipped with front and rear safety lights, and low-cost LED lights can transform a cyclist from invisible to highly visible, particularly on those streets that are not well-lit.”

The ride starts at 8 p.m. and participants should plan to arrive at the Community Park South parking lot around 7:30 p.m. for registration and to have the tail lights attached. The tail lights will be re-used and should be returned at the end of the ride.

“Thanks are due to Ben Stentz and the folks in Princeton’s Recreation Department who are working to make sure that the paved bike path around Community Park South is clear of snow/ice and other debris such as branches,” said Mr. Kruse, who emphasized that since the path has no reflective striping, headlights are a must for every participant.

To pre-register and guarantee participation in the ride email princetonmimi@gmail.com.

Pi Day Events

The “Fireflies Ride” is just one of a host of activities at this year’s Pi Day.

Founded by Mimi Omiecinski in recognition of Princeton’s most famous resident and the happy coincidence that his March 14, or 3/14, birthday matches the first three digits of the mathematical constant Pi (), Pi Day has grown each year since it began in 2009 to include local merchants, the Historical Society of Princeton, the Princeton Public Library, and scores of clubs, groups, academic institutions, non-profit organizations, musicians, authors, and interested locals.

“Every year something new gets added that I can’t believe wasn’t always a part of the event,” said Ms. Omiecinski. “Last year it was Princeton University’s Rubiks cube club, this year Tetsuya Miyamoto, the inventor of KenKen, will be joining us, and I’m really excited about the new Princeton Pi pizza competition, which is sure to become one of our annual core events.” The competition takes place on March 14, at 3:14 p.m. Contestants will have five minutes to choose from all the ingredients at Princeton Pi to create the best pizza. Judges include Mayor Liz Lempert and Superintendent of Princeton Regional Schools Steve Cochrane.

As well as tours and talks by famed physicists, other highlights include a Pi recitation contest, an apple pie contest, a pie-throwing contest, and a Dinky ride with Einstein.

Events begin Thursday, March 13, when author Charles Adler presents “Wizards, Aliens, and Starships: Physics and Math in Fantasy and Science Fiction” at the Princeton Public Library at 7 p.m.

On Saturday, the fun starts at 9 a.m. with a Pie Eating Contest at McCaffrey’s, followed by kids events at the Princeton Public Library: the Kids’ Violin Exhibition, the Einstein Look A Like Contest and a “Happy Birthday Einstein!” party at 11 a.m. at the Princeton Historical Society. Tetsuya Miyamoto will appear at noon, followed by a KenKen Tournament for Teens (and other teen-spirited humans).

“The whole town ‘gloms’ onto the celebration and brings the distinctive creativity of Princeton to the event. It feels as if Pi Day has always been here,” said Ms. Omiecinski.

Advanced registration and early arrival are recommended for Pi Day events. For more information and a full schedule of events, visit www.pidayprinceton.com.