Einstein's Dreams - Alan Lightman [26]
Thus, on any day, at any hour of any day, a line of ten thousand stretches radially outward from the center of Rome, a line of pilgrims waiting to bow to the Great Clock. They stand quietly, reading prayer books, holding their children. They stand quietly, but secretly they seethe with their anger. For they must watch measured that which should not be measured. They must watch the precise passage of minutes and decades. They have been trapped by their own inventiveness and audacity. And they must pay with their lives.
• 20 June 1905
In this world, time is a local phenomenon. Two clocks close together tick at nearly the same rate. But clocks separated by distance tick at different rates, the farther apart the more out of step. What holds true for clocks holds true also for the rate of heartbeats, the pace of inhales and exhales, the movement of wind in tall grass. In this world, time flows at different speeds in different locations.
Since commerce requires a temporal union, commerce between cities does not exist. The separations between cities are too great. For if the time needed to count a thousand Swiss franc notes is ten minutes in Berne and one hour in Zürich, how can the two cities do business together? In consequence, each city is alone. Each city is an island. Each city must grow its own plums and its cherries, each city must raise its own cattle and pigs, each city must build its own mills. Each city must live on its own.
On occasion, a traveler will venture from one city to another. Is he perplexed? What took seconds in Berne might take hours in Fribourg, or days in Lucerne. In the time for a leaf to fall in one place, a flower could bloom in another. In the duration of a thunderclap in one place, two people could fall in love in another. In the time that a boy grows into a man, a drop of rain might slide down a windowpane. Yet the traveler is unaware of these discrepancies. As he moves from one timescape to the next, the traveler’s body adjusts to the local movement of time. If every heartbeat, every swing of a pendulum, every unfolding of wings of a cormorant are all harmonized together, how could a traveler know that he has passed to a new zone of time? If the pace of human desires stays proportionally the same with the motion of waves on a pond, how could the traveler know that something has changed?
Only when the traveler communicates with the city of departure does he realize he has entered a new domain of time. Then he learns that while he has been gone his clothing shop has wildly prospered and diversified, or his daughter has lived her life and grown old, or perhaps his neighbor’s wife has just completed the song she was singing when he left his front gate. It is then the traveler learns that he is cut off in time, as well as in space. No traveler goes back to his city of origin.
Some people delight in isolation. They argue that their city is the grandest of cities, so why would they want communion with other cities. What silk could be softer than the silk from their own factories? What cows could be stronger than the cows in their own pastures? What watches could be finer than the watches in their own shops? Such people stand on their balconies at morning, as the sun rises over the mountains, and never look past the outskirts of