Fifty Years Ago: Topology of Manifolds in the 50’s and 60’s
نویسندگان
چکیده
A number of mathematicians worked on 3-dimensional manifolds in the 50’s. (I was certainly one of them.) But I believe that the most important contribution was made by just one person. Christos Papakyriakopoulos had no regular academic position, and worked very much by himself, concentrating on old and difficult problems. We were both in Princeton during this period, and I saw him fairly often, but had no idea that he was doing such important work. (In fact, I don’t really remember talking to him—perhaps we were both too shy.) Let me try to explain what he accomplished. In 1910, Max Dehn had claimed a proof of the following lemma:
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