Exploring the true nature of time
By Amanda Jermyn

As the ball in Times Square dropped and the champagne popped, I began to think about the New Year and what it really means. We all know that a year is roughly 365 days, and that this is the time it takes for the earth to make one complete revolution around the sun. However, the exact arrival of the New Year occurs at different moments in the various time zones around the globe. In addition, other cultures celebrate the New Year at very different times. The Jewish New Year, which is dependent on a lunar calendar, usually occurs in September while the Chinese New Year, also lunar based, falls somewhere between January 21st and February 21st, and there are many others. When it comes down to it, there’s nothing intrinsically different about January 1st as compared to December 31st of the previous year. What you’re really noting, in your New Year’s celebration, is the passage of time.

Ancient civilizations marked the passage of time by the rising and setting of the sun, the waxing and waning of the moon, and the changing seasons on which their agriculture depended. Later they invented devices such as sundials, hour glasses and clocks to mark the passing of time. There is a sense in which time involves motion – the rotation of the earth about its axis, the swing of a pendulum, the beating of the heart. It’s a concept we think we understand perfectly until we’re asked to define it. The more deeply we consider it the harder it becomes to understand what time really means.
One can think about time as an ordering of events into past, present and future, or as a measure of how long something takes to occur. We see its effects in the growth of a child or the wrinkles on an aged face, but how time itself is actually felt or experienced is not clear.

Time has been quantified into years, months, days, hours, minutes and seconds, based on the motions of the heavenly bodies, yet today’s scientific definition has evolved. The second is now the official base unit of time, and is defined in terms of the lifetime of an excited state of the cesium atom.

A major shift in thinking about time occurred with Einstein’s revolutionary concept of spacetime. According to his theory of special relativity, the concept of time depends on the spatial reference frame of the observer. A classic example used to explain this involves a set of twins. One remains on earth while the other travels in a rocket at high speed, say, half the speed of light. The traveler returns to earth to find his twin has aged much more than he has. For the traveler, time slows down, and what seems like seconds for him in his rocket would feel like an eternity to the twin who remained on earth. Both time concepts are valid because time is dependent on how fast you are traveling. Recent experiments have confirmed that an atomic clock traveling on a high speed aircraft slows down by a very small, though measurable amount, relative to an atomic clock on earth.

At the cosmic level, many scientists view time as beginning with the Big Bang. What might have existed before this is currently in the realm of speculation. Was there something or nothing before our universe was born? According to Stephen Hawking, even if time existed before the Big Bang, no information from events then would ever be available to us. With new scientific discoveries our understanding of time continues to evolve, yet its true nature eludes us. So many mysteries, so little time…

Join the Springfield Stars Club on Tuesday, February 26th at 7:30pm at the Springfield Science Museum for a talk by Richard Sanderson on “The Korkosz Brothers and their Amazing Star-Ball.” Sanderson will trace the history of the Springfield Science Museum’s 75-year-old Seymour Planetarium, the oldest operating planetarium in the United States, and the lives of the two brothers from Chicopee who created it. Sanderson will also discuss other devices that over the centuries have sought to recreate the heavens. The talk will be illustrated with rare, historic photos from the museum’s collection. Sanderson began his association with the planetarium as a 15-year-old museum volunteer and was trained to use the star-ball by its co-creator Dr. Frank Korkosz, who was at that time director of the Science Museum. Sanderson is curator of physical science at the Springfield Science Museum and manages the museum’s Seymour Planetarium and Observatory. He is also an astronomy writer and past president of the Springfield Stars Club. Refreshments will be served, and the public is welcome free of charge.

Also, on Friday, March 1st at 7:30pm the Stars Club and Springfield Science Museum will host “Stars over Springfield,” an astronomy adventure for the whole family. Alan Rifkin, president of the Stars Club, will present “How the seasons happen.” A fee of $3 for adults and $2 for children under 18 will be charged.