Inspired by Lurie’s theory of quasi-unital algebras we prove an analogous result for ∞–categories. By constructing a suitable model category of non-unital complete Segal spaces, we show that the unital structure of an ∞–category can be uniquely recovered from the underlying non-unital structure once suitable candidates for units have been identified. The main result of this paper can be used to produce a proof of the 1–dimensional cobordism hypothesis, as described in a forthcoming paper of the author.
Keywords: higher category theory, complete Segal spaces, units
Harpaz, Yonatan  1
@article{10_2140_agt_2015_15_2303,
author = {Harpaz, Yonatan},
title = {Quasi-unital \ensuremath{\infty}{\textendash}categories},
journal = {Algebraic and Geometric Topology},
pages = {2303--2381},
year = {2015},
volume = {15},
number = {4},
doi = {10.2140/agt.2015.15.2303},
url = {http://geodesic.mathdoc.fr/articles/10.2140/agt.2015.15.2303/}
}
Harpaz, Yonatan. Quasi-unital ∞–categories. Algebraic and Geometric Topology, Tome 15 (2015) no. 4, pp. 2303-2381. doi: 10.2140/agt.2015.15.2303
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