We are rapidly approaching my favorite position in time. That's when the sun, moving from north to south, crosses the Celestial Equator just north of Corvus the Crow. Only those knowledgeable in astronomy will understand this point in the sky. The sun, upon reaching that intersection, marks the end of summer and the beginning of my favorite season - autumn. The natural year reaches maturity at this point in time. Berries, nuts, wild grapes and corn ripen. Goldenrod and purple aster transform drab fields into works of art. Dogwood and Virginia creeper turn crimson to advertise their fruit to migrating songbirds. The woodchuck puts on weight and the hawks migrate down the ridges. We look for frost, anxiously await the coloring of the leaves and enjoy the lengthy size illusion of the harvest moon as it slowly ebbs above the landscape and stealthily steals across the horizon at its lowest angle of the year.
These events have been happening for millennia, but only by Nature's time table, not by those technical time pieces called clocks, watches and calendars.
The concept of time is a fascinating enigma. What exactly is it? Why and how does time run at different speeds? When did time start? Was there no time before the Big Bang? What would happen if you came to a point where time stops? Or begins running backward? Such a place may actually exist, but more about that later. There are different kinds of time. There is psychological time, calendar time, star time and biological time. We all notice at an early age how much our perception of time varies. Sometimes it goes slow, at other times fast. Older folk will agree that time changes overall speed as we age. Time dragged when I was young and impatient, but as I grew older I acutely noticed how much time picked up the pace. Now that I want it to drag, it goes faster than ever and nothing seems to slow it down.
Apparently our perception of time is related to our physiology. It is an inverse relationship. The faster our metabolism, the slower time goes. As our metabolism decelerates with age, time speeds up. Is this also why our dogs are so happy to see us when we return home after a few hours absence? Their metabolisms are much faster than ours and those few hours probably seem like eternity to them.
We are impressed and amazed that the humpback whale, which has a very slow metabolism, can accurately repeat over and over a song that is several hours long. Could we humans repeat a poem that takes two hours to read- and do it accurately? It sounds like whales are incredibly intelligent, or do those hours seem like only a few minutes to a whale and the repetition of their song is as easy as us reciting a sonnet? Psychological time is indeed intriguing.
Then there's calendar time which is human arranged time. This is an imperfect contrivance of man based on stars and the sun. The history of our calendar would require a book. All calendars are slightly and permanently flawed because none of the figures upon which we base our calendar are evenly divisible. A year is not exactly 365 days, but 365 days, five hours, 48 minutes and 46 seconds. Obviously a day has to be added every four years. Julius Caesar, in 46 B.C., was the first to decree that every 4th year would have an extra day or leap year. If you do the arithmetic, however, you'll see this one day correction isn't perfect and contains a gain of one day every 128 years. By the 16th century the calendar was 13 days behind the sun and Easter was fast becoming a summer festival which greatly annoyed the Catholic Church. Pope Gregory, in 1582, ordered the following year be shortened by10 days and that three leap years be omitted every four centuries. This brings our current calendar accurate to within one day every 3,323 years. English and American Protestants, however, did not follow suit until 1752 when they had to cut 11 days from the calendar and English landlords rioted because they had been cheated out of 11 days rent. The history of our imperfect calendar has many entertaining tales.
Then there's space-time. I've been a Star Trek fan since its inception, but I've always been somewhat annoyed how they conveniently ignore Einstein's theory and treat time as though it was the same throughout the universe. I have no idea why the Voyager crew wants to go home when all their friends and relatives are dead. This may require some explanation for some.
In 1887, two physicists, Albert Michelson and Edward Morley, using mirrors, devised an ingenious experiment to test the effect of the earth's velocity on the speed of light. In other words, does the speed of the earth in orbit (18.5 miles per second) add to the speed of light (186,000 mps) in the direction of travel? To their astonishment, there was no effect. Light traveled at the same speed no matter what the speed of the source. To put this in understandable terms, if a baseball pitcher delivers a 100mph pitch from a car speeding toward the batter at 50 mph, the batter will see the ball approaching at 150 mph. The speed of the car adds to the speed of the ball, but, as Michelson and Morley discovered, this doesn't happen with light. Suppose a train with a headlight beam were approaching a station at half the speed of light. The train engineer would see his headlight beam flash before him at the speed of light, but would the man at the train station see the headlight beam approach him at one and one half times the speed of light? No. He would also record it at the speed of light or 186,000 miles per second. Michelson and Morley had to declare that the speed of light was a constant, but how can this be? Einstein resolved the paradox by realizing that the train engineer and the train station man were timing the light beam with two different clocks. A second on the train was much longer than a second at the train station. Time itself travels slowly at high speed and faster at low speed, just like our metabolism. Our astronauts return home a little younger than they would have been had they stayed on earth. Why? Since time slows with higher speed we therefore age less fast. Our heartbeat slows down and we don't burn out as quickly. We don't realize this because the watch we time the heartbeat with has also slowed down. This is due to the fact that mass also increases along with velocity, something I accept, but don't comprehend. The watch is heavier and runs slower. Those looking for the fountain of youth will find it in spacetravel. You can leave on a ship, travel and age for one year by your clock and return to find earth may have circled the sun fives times during your absence, so why should the passengers aboard Voyager want to go home? At the speeds they travel, the earth would have aged centuries in the five years they were gone. Though highly entertaining, Star Trek programs ignore the time differences and the fact warp speeds are impossible. This consideration would make the show more educational and realistic. However, a friend of mine, WendyJo Shemansky, who does research in psychology, says who needs reality? We live in the real world 23 hours a day. It's nice for one hour a week to drift into fantasy watching Star Trek. She has a point, despite the fact that in this case, the real world is stranger than fantasy.
High gravitational fields also slow time. I do not understand why, but it explains why time at the event horizon of a black hole slows almost to a stop, or does it actually stop and begin running backward as you enter the hole? I have read Stephen Hawking's "A Brief History of Time," but I still don't quite understand what happens to time in a black hole. The real world is indeed stranger than fiction and TV writers could go bananas with that.
And finally there's biological time. Unlike human calendars, nature's calendar never gets out of step with the sun. The birds still fly south and the leaves change color when conditions are ripe. Nature has many timepieces. Any physical phenomena may be used as a clock. You can time things by your heartbeat. Ducks flying south can serve as a clock. My morning glories open at daybreak and are closed by noon, another type of clock. A tree makes buds in the summer, drops it's leaves in the fall, opens its buds the following spring and leafs out, all in very timely order. Shad and salmon come upstream when conditions beckon. These fish congregate at the stream's mouth at the appropriate time without calendars. At some point in the summer the groundhog begins putting on weight without a change in diet. Annual cicadas break ground almost on cue and begin their buzzing songs in the trees. Snowshoe hares begin changing coat color in August. Moose living in wolf territory all give birth within a narrow 10 day period, even though they may have bred a month apart, to reduce the period of easy kill opportunity of their predators. There are built-in rhythms throughout nature. These mysterious timing devices are referred to by scientists as biological clocks. They are set to solar, lunar and tide cycles. Much experimentation has been done in the past decades on resetting these bio- clocks. We humans have built-in clocks too, which makes jet-lag a real problem.
Time is an intriguing concept in many aspects. We are surrounded by clocks and a constantly changing environment as the biological year progresses. Time's definition, in all its forms, will haunt me to the end of my time.
