Time difference: 0.01 sec. (17.3 cm)
Time is an abstract idea. Nevertheless it plays an important part in daily life, maybe more than any other concept. It is not only interesting for physicists but everybody has an idea of time and every culture, too. This is not surprising for time structures life, not only on a personal level but also on a social level. The structuring power of time can be explained, I think, by a feature that I mentioned already in my last blog: Time develops continuously in one direction and never stands still. This makes that every decision involving time must be a good decision for it cannot be reversed. Actually, it is true for each decision, anyhow, for each decision takes place on the time dimension, but when time is an essential aspect, it is more true than when time is only of secondary importance. In case I turn left on a corner where I had to turn right, I simply return and continue on the right way. Usually this mistake has no important consequences. However, when time is a primary factor in a decision it is different. Just such decisions are often crucial in life. A farmer must decide when to sow; too early or too late can end in a poor harvest. A driver must brake at the right moment; too late can cause an accident, too early sometimes, too.
These examples show the relevance of time in momentary cases, but there is also a long run significance of time. The recurrence of seasons does not only affect when a farmer has to sow but also what to do next in the course of the year after the setting. It is the same when a youngster is thinking about her career. A decision on her future profession determines not only the contents of her study but also the time path to her goal. Moreover, she must realize that once the decision has been taken and the education has begun, it is difficult to reconsider it. Often schools accept only students of a certain age, grants are not given above a certain age, and when she ends her study too late, it will be difficult to get a job. Also a government that prepares an estimate does not only divide the money among the departments; it has to present the budget at the right date as prescribed by law; take care that the money can be spent; and that the money really will be paid, for instance. In short, on every level of life − both on an individual level and on a social level − time planning plays an important role; short-term and long-term.
As we have seen, we can decide on our time, for instance when we make a time planning, but time can also decide on us. Time is always developing, and when we do not take the right decision at the right moment but too late, whatever the reason may be, time works against us. This can also be so when what happens is beyond our power. To take a Dutch example, a dike subsides because it has been undermined by muskrats. The tide is coming in and we have only two hours to prevent the polder behind the dike being flooded. But we need at least five hours for closing the hole: Time works against us.
This makes me think of an incident after the 500 m race in speed skating for men on the present Winter Olympics. All participants have already long careers behind them. Once it had become clear that they had the talent of becoming top skaters, they started to plan the training through the years hoping to become finalists in the Games: How to train when and where and in which races to participate in order to have a chance to be there. It involved a global time planning for the years to come, later to be filled in with a more detailed time planning. Long run time planning and short run planning were made to fit. And then they are really there: thirty skaters who are the best of the world on the 500 m. Most of them skate the best races of their lives. They couldn’t skate the two heats faster in those conditions. They skate in pairs and the winner of the first heat starts in the last pair. He finishes, sees his time and shouts with joy: The gold medal is for me! For my overall time of both heats is better than the overall time of the winner of the second heat. But a few moments later ... disappointment, for during his race the time of the latter had been corrected, which makes that not he but the winner of the second heat has the best overall time. The difference is just a tiny one hundredth of a second over two races, so over 1,000 metres in total. A mere one hundredth of a second in time decides on a gold medal, on the career of a speed skater and maybe also on the course of the rest of a life.