English

Projective and injective objects in symmetric categorical groups

Category Theory 2010-07-02 v1

Abstract

We prove that the 2-category of symmetric categorical groups have enough projective and injective objects. This was conjectured by Bourn and Vitale in 2002 and was anounced recently by Fang Huang, Shao-Han Chen, Wei Chen and Zhu-Jun Zheng in arXiv:1006.4677 with wrong proof.

Cite

@article{arxiv.1007.0121,
  title  = {Projective and injective objects in symmetric categorical groups},
  author = {Teimuraz Pirashvili},
  journal= {arXiv preprint arXiv:1007.0121},
  year   = {2010}
}
R2 v1 2026-06-21T15:43:23.981Z