Constantine Karatheodori (1873–1950) was a pioneering Greek mathematician whose contributions to real and complex analysis, thermodynamics, and the calculus of variations influenced some of the greatest minds of the 20th century—including Albert Einstein. His expertise in Hamilton-Jacobi equations and canonical transformations helped Einstein refine his general theory of relativity. Karatheodori held prestigious academic positions across Europe, played a key role in Greek higher education, and left a lasting legacy in both pure and applied mathematics.
