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arXiv · 2108.13745

On Infinite Matroids with Strong Maps: Proto-exactness and Finiteness Conditions

Chris Eppolito·Jaiung Jun
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Abstract

This paper investigates infinite matroids from a categorical perspective. We prove that the category of infinite matroids is a proto-exact category in the sense of Dyckerhoff and Kapranov, thereby generalizing our previous result on the category of finite matroids. We also characterize finitary matroids as co-limits of finite matroids, and show that the finite matroids are precisely the finitely presentable objects in this category.

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Chris Eppolito, Jaiung Jun. 2021-08-31. On Infinite Matroids with Strong Maps: Proto-exactness and Finiteness Conditions. https://arxiv.org/abs/2108.13745

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