François Arago

The ideas here are retold from the historical record, drawn from the sources each event cites. François Arago never posted on Veritula. To report a mistake, email veritula@dennishackethal.com.

Chronicled events

1. March 15, 1819·​A Bright Spot Where There Should Be Shadow
   #5824

   I put a small round disk in a narrow beam of light, and the bright spot is there, at the center of its shadow, just as Fresnel’s theory says.