About Christos Papakyriakopoulos
Christos Dimitriou Papakyriakopoulos, commonly known as Papa, was a Greek mathematician specializing in geometric topology. Papakyriakopoulos is best known for his proofs of Dehn's lemma, the loop theorem, and the sphere theorem, three foundational results for the study of 3-manifolds. But he was enrolled as research student at Athens University, being awarded a PhD in 1943 on the recommendation of Constantin Carathéodory.
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