time reversal

American  

noun

Physics.

1. the mathematical operation of reversing the direction of time. T

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time reversal Scientific  

1. A mathematical operation on the description of a physical system in which the signs of variables representing time are reversed.

2. Also called time conjugation

3. See more at invariance

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Etymology

Origin of time reversal

First recorded in 1920–25

Example Sentences

In an antiferromagnet, the flipping of spins associated with time reversal changes the pattern of alternating spins.

From Nature • Dec. 17, 2019

The direction of the sequence is fundamentally arbitrary, yet if you grouped it the wrong way, it would look like a time reversal.

From Salon • May 16, 2013

For this, Lerosey and his team used a method known as time reversal: they recorded the sound above any one can in the resonating array, and then played the recording backwards through the speakers.

From Scientific American • Jul. 8, 2011

Such results indicated a possible violation of another basic presumption of symmetry known as time reversal: that reactions can run either forward or backward, like film in a movie projector.

From Time Magazine Archive

Theoretical physicists find the situation intriguing: if the laws that govern nature really permit time reversal, there should somehow be a way to achieve it.

From Time Magazine Archive