, Volume 180, Issue 3, pp 337–356 | Cite as

How Galileo dropped the ball and Fermat picked it up

  • Bryan W. RobertsEmail author


This paper introduces a little-known episode in the history of physics, in which a mathematical proof by Pierre Fermat vindicated Galileo’s characterization of freefall. The first part of the paper reviews the historical context leading up to Fermat’s proof. The second part illustrates how a physical and a mathematical insight enabled Fermat’s result, and that a simple modification would satisfy any of Fermat’s critics. The result is an illustration of how a purely theoretical argument can settle an apparently empirical debate.


Foundations of physics History of mathematics Freefall Acceleration Galileo Fermat 


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© Springer Science+Business Media B.V. 2009

Authors and Affiliations

  1. 1.Department of History and Philosophy of ScienceUniversity of PittsburghPittsburghUSA

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