A critical review of a Galileo thought experiment on falling bodies and the design of an alternative experiment

Authors

Keywords:

Galileo and Aristotle, thought experiment and real experiment, free falling bodies, equivalence of inertial and gravitational mass

Abstract

In the thought experiment that we study in this article, Galileo attempts to refute the Aristotelian hypothesis that heavier bodies should take less time to fall than lighter ones. After pointing out some inconsistencies in Galileo's approach, we show, through the design of two alternative but equivalent experiments to his, that from his imaginary experiment it is not possible to reach the conclusion that all bodies fall simultaneously into a vacuum. In turn, we design a thought experiment from which it follows that, under the same initial conditions, all bodies, regardless of their weight and composition, must fall with the same acceleration. We show why, to explain the result of this type of experiences, whether real or imaginary, it is necessary to establish the equivalence between inertial and gravitational masses, equivalence derived exclusively from experience and that gave rise to the so-called Equivalence Principle as used in the General Theory of Relativity.

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Published

2021-11-10

How to Cite

A critical review of a Galileo thought experiment on falling bodies and the design of an alternative experiment. (2021). Epistemología E Historia De La Ciencia, 6(1), 69-87. https://revistas.unc.edu.ar/index.php/afjor/article/view/32649