Margherita Piazzola Beloch
Margherita Piazzola Beloch (1879–1976) was an Italian mathematician who worked in algebraic geometry, algebraic topology, and photogrammetry. She was born in Frascati, the daughter of German historian Karl Julius Beloch and American Bella Bailey. She studied at Sapienza University of Rome, where Guido Castelnuovo supervised her bachelor thesis on birational transformations in space. She earned her degree in 1908 with high honors, and her work was published.
Castelnuovo hired her as his assistant, a position she held until 1919, when she moved to Pavia. In 1920 she went to Palermo to work with Michele De Franchis. In 1924 she completed her libera docenza, and in 1927 she became a full professor at the University of Ferrara, where she taught until retirement in 1955. She died in Rome in 1976.
Her main research was in algebraic geometry and topology, with later work in photogrammetry. She studied how to classify algebraic surfaces by the lines and curves they contain, and showed that hyperelliptic surfaces of rank 2 have 16 rational curves. She also contributed to the theory of skew algebraic curves and to the topological properties of algebraic curves on various surfaces. Around 1940 she grew more interested in applying mathematics to photogrammetry.
She also helped develop the mathematics of paper folding. She formalized an origami move to construct tangents to two parabolas and showed how to fold paper to extract cubic roots, something not possible with ruler and compass. This folding move is now known as the Beloch fold.
This page was last edited on 2 February 2026, at 05:49 (CET).