Euler, Dollond, and the Achromatic Telescope Controversy

Erik Tou, Carthage College (and Gustavus alumnus)
11:30-12:20 on Wednesday, December 12, 2007
Olin Hall, Room 320
Lunch will be served

Leonhard Euler was the most prolific mathematician of the 18th century. He wrote over 800 books and papers during his career, many of which were published long after his death. While much of Euler’s work was in mathematics, he also made contributions to fluid mechanics, astronomy, and optics. In this talk, we focus on the brief correspondence between Euler and the English optician, John Dollond. Dollond was particularly interested in telescope design, and wrote to Euler of a mathematical flaw that he had discovered in one of Euler’s papers on the subject. Was Dollond right and Euler wrong? Or was Euler correct? We will briefly survey Euler’s connection to English science and scholarship, and ook at a new translation of Euler’s letter to Dollond.

This talk should be accessible to anyone who is reasonably comfortable with the natural logarithm function. The speaker will introduce the concept of an achromatic telescope, as well as the idea of infinitesimals. Most of the talk is on the historical angle, with a small portion focusing on the mathematical controversy.