Charles Guye (15.10.1866-15.07.1942) was a Swiss experimental physicist. He was born in Saint-Christophe. In 1889 he received his doctorate at the University of Geneva. In 1894 — 99 he was professor at the Zurich Polytechnic and in 1900 — 30 at the University of Geneva.
His research concerned electromagnetism, molecular physics, precision instrument-making, the experimental confirmation of relativistic dynamics and statistical thermodynamics. He invented a number of precision instruments, developed a technique for measuring the deflection of particles in electromagnetic fields, and made precise measurements of the mass of the electron as a function of its velocity. He obtained results confirming Lorentz's formulae in relativistic dynamics and Einstein's theory of relativity. He determined the diameters of molecules.
A member of the Paris Academy of Sciences (1929).