Physics World

Experiment sees the arrow of time – at last!

Nick E. Mavromatos

Published Dec 1, 1998• 2 citations

Abstract

Everyday experience tells us that it is impossible to travel backwards in time, no matter what science-fiction writers and movie directors tell us. However, this seemingly natural impossibility is actually one of the greatest mysteries in physics. Currently most physicists associate the irreversibility of time with the production of entropy in the warm macroscopic world. One consequence of this irreversibility – often called the “arrow of time” in thermodynamics is the ageing process. In plain terms, one grows old because of the irreversible physical processes that occur during one's life. However, the fundamental classical laws of physics discovered by Galileo, Newton and Einstein do not distinguish between the future and the past. In other words, they appear to be symmetric in time.

DOI: 10.1088/2058-7058/11/12/19

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