Why Time Flies

The Beginning of Time

People struggle with the notion that time came into existence only with the Big Bang. In The Confessions, begun in the year 397 AD, Christian philosopher Augustine of Hippo – later sainted – considered time, theology and eternity. Now as then, time’s multifaceted ineffability is fascinating. As science probes further into the mysteries of the mind, time appears inextricably bound up with consciousness. Consider four perspectives:

1. “The Hours”

The International Bureau of Weights and Measures (the Bureau), near Paris, is headquarters to global scientists who calibrate the world’s units of measure – including the meter, the kilogram and the second. The world’s timepieces – including those on GPS satellites – keep in step by syncing with the Bureau’s Coordinated Universal Time (UTC).

Historically, people used Earth’s rotation as their master clock, tracked with sundials and early water clocks. In 1656, Christiaan Huygens invented the gravity-driven pendulum clock. In 1670, William Clement’s clock was the first to tick-tock the seconds – like hours and minutes, a human-devised division of the day.

Up to the early 20th...