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arXiv · 1411.7709

A categorification of the square root of -1

Yin Tian
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Abstract

We give a graphical calculus for a monoidal DG category $\cal{I}$ whose Grothendieck group is isomorphic to the ring $\mathbb{Z}[\sqrt{-1}]$. We construct a categorical action of $\cal{I}$ which lifts the action of $\mathbb{Z}[\sqrt{-1}]$ on $\mathbb{Z}^2$.

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Yin Tian. 2014-11-27. A categorification of the square root of -1. https://arxiv.org/abs/1411.7709

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