Light Touch
Arago’s Inadvertent Test of Relativity
Nearly 100 years before Einstein’s special theory of relativity, François Arago unknowingly found the first experimental evidence for it.
Portrait of Arago.
Wikimedia Commons/Engraving by A.V. Sixdeniers/Painting by H. Scheffer
The year 2010 marked an unusual and little known milestone in the history of physics: the 200-year anniversary of the first experimental evidence for Einstein’s special relativity. In 1810, French physicist François Arago (1786-1853) attempted and failed to measure expected variations in the speed of light coming from distant stars. Of course, Einstein’s theory of special relativity, which postulates the constancy of the vacuum speed of light, would not be proposed until 1905. Arago didn’t discover relativity, but his experiment nevertheless had a remarkable influence on 19th century physics and a role in the acceptance of the wave theory of light.
…Log in or become a member to view the full text of this article.
This article may be available for purchase via the search at Optica Publishing Group.
Optica Members get the full text of Optics & Photonics News, plus a variety of other member benefits.