Eugenio Calabi is an Italian-American mathematician known for his significant contributions to differential geometry and complex geometry. He is particularly famous for the Calabi conjecture, which relates to the existence of certain types of metrics on complex manifolds. His work has had a profound impact on various fields, including string theory and mathematical physics. Born on January 2, 1928, Calabi has held academic positions at several prestigious institutions, including University of Pennsylvania and University of California, Berkeley. His research has influenced many mathematicians and has led to advancements in understanding the geometry of Kähler manifolds and Calabi-Yau manifolds.