Steve Nadis in Quanta:
Eugenio Calabi was known to his colleagues as an inventive mathematician — “transformatively original,” as his former student Xiuxiong Chen put it. In 1953, Calabi began to contemplate a class of shapes that nobody had ever envisioned before. Other mathematicians thought their existence was impossible. But a couple of decades later, these same shapes became extremely important in both math and physics. The results ended up having a far broader reach than anyone, including Calabi, had anticipated.
Calabi was 100 years old when he died on September 25, mourned by his colleagues as one of the most influential geometers of the 20th century. “A lot of mathematicians like to solve problems that finish off work on a particular subject,” Chen said. “Calabi was someone who liked to start a subject.”
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