arXiv · 1804.07857
We give a description up to homeomorphism of $S^3$ and $S^2$ as classifying spaces of small categories, such that the Hopf map $S^3\to{}S^2$ is the realization of a functor.
Björn Gohla. 2018-04-20. A Categorical Model for the Hopf Fibration. https://arxiv.org/abs/1804.07857
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