Dutch physicist who, with Ralph de Laer Kronig, derived important equations relating the absorption to the dispersion of light. He also predicted (1924) the existence of the Raman effect, an inelastic scattering of light, and showed (1927) that the complex form of the mathematical functions in dispersion theory, concerning collisions of subatomic particles, results from the inability of a signal to be propagated faster than the speed of light.

Kramers' research on X rays resulted in his development of equations to determine the efficiency and intensity of X-ray production.