twin paradox

British  

noun

1. a phenomenon predicted by relativity. One of a pair of identical twins is supposed to live normally in an inertial system whilst the other is accelerated to a high speed in a spaceship, travels for a long time, and finally returns to rest beside his twin. The travelled twin will be found to be younger than his brother

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twin paradox Cultural  

1. An effect predicted by the general theory of relativity: if one of a pair of twins remains on Earth, and the other travels in a rocket at a speed near the speed of light, the traveling twin will be younger than the earthbound twin upon returning to Earth. This effect has been verified experimentally by measurements with atomic clocks.

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Example Sentences

Einstein’s relativity, for instance, introduced the so-called twin paradox, which illustrates how a rapid journey through space and time can make one woman age more slowly than her twin.

From The New Yorker • Feb. 7, 2017

Figure 28.8 The twin paradox asks why the traveling twin ages less than the Earth-bound twin.

From Textbooks • Aug. 12, 2015

If you use special relativity to examine the twin paradox, you must keep in mind that the theory is expressly based on inertial frames, which by definition are not accelerated or rotating.

From Textbooks • Aug. 12, 2015

The twin paradox asks why a twin traveling at a relativistic speed away and then back towards the Earth ages less than the Earth-bound twin.

From Textbooks • Aug. 12, 2015

You can also use general relativity to address the twin paradox and, according to general relativity, the astronaut will age less.

From Textbooks • Aug. 12, 2015