English

Weak Fraisse categories

Category Theory 2021-08-25 v3 Logic

Abstract

We develop the theory of weak Fraisse categories, where the crucial concept is the weak amalgamation property, discovered relatively recently in model theory. We show that, in a suitable framework, every weak Fraisse category has its unique limit, a special object in a bigger category, characterized by certain variant of injectivity. This significantly extends the present theory of Fraisse limits.

Keywords

Cite

@article{arxiv.1712.03300,
  title  = {Weak Fraisse categories},
  author = {Wieslaw Kubiś},
  journal= {arXiv preprint arXiv:1712.03300},
  year   = {2021}
}

Comments

Several examples and comments added; new subsection 6.2 (38 pages)

R2 v1 2026-06-22T23:12:52.062Z