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Di-extensions in monoids and unital magmas

Decide whether, in each of the categories Mag of unital magmas and Mnd of monoids, every short exact sequence of short exact sequences is a di-extension.

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Background

Di-extensions (3×3-diagrams with exact rows and columns) are central to the homological framework. While they hold broadly in di-exact settings, it is unclear whether categories like monoids and unital magmas satisfy the di-extension property for all short exact sequences of short exact sequences.

References

We also turned certain questions which we currently are unable to answer into exercises; these are labelled 'ANK' for 'answer not known'. In each of the categories Mag of unital magmas or Mnd of monoids decide if every short exact sequence of short exact sequences is a di-extension.

A Homological View of Categorical Algebra (2404.15896 - Peschke et al., 24 Apr 2024) in Exercise 2.1.22 (Di-extensions in Mnd and Mag) - Section 2.1