Emilie Du Chatelet

Émilie du Châtelet was a prominent figure of the French Enlightenment, known for integrating theoretical work and experiment in physics and mathematics. An author and researcher, she published in 1737 an essay on the nature and propagation of fire that anticipated the concept of infrared radiation and, in 1740, Institutions de Physique — a pedagogical work that reconciled ideas from Leibniz, Willem Jacob ’s Gravesande and others, explaining the relationship among mass, velocity and kinetic energy (E ∝ mv²).

Her intellectual collaboration with Voltaire, sustained at Cirey-sur-Blaise, played a decisive role in spreading Newtonian ideas in France; together they conducted experiments on heat and energy that reinforced observations of Newtonian mechanics. The culmination of her work was the French translation of Newton’s Principia Mathematica, published posthumously in 1759, accompanied by extensive commentary and notes that made the work a reference throughout continental Europe.

Raised in letters, languages and the sciences, Du Châtelet combined learning with pedagogical skill, translating classics and writing for both lay and academic readers. Her advocacy of the concept of “vis viva” proportional to the square of velocity and her critical readings of physical concepts influenced the development of modern physics and solidified her standing as an authority on Newtonian physics.