English

Poset algebras over well quasi-ordered posets

General Topology 2012-10-23 v1 Logic

Abstract

A new class of partial order-types, class \gbqo+\gbqo^+ is defined and investigated here. A poset PP is in the class W+W^+ iff the free poset algebra F(P)F(P) is generated by a better quasi-order GG that is included in the free lattice L(P)L(P). We prove that if PP is any well quasi-ordering, then L(P)L(P) is well founded, and is a countable union of well quasi-orderings. We prove that the class W+W^+ is contained in the class of well quasi-ordered sets. We prove that W+W^+ is preserved under homomorphic image, finite products, and lexicographic sum over better quasi-ordered index sets. We prove also that every countable well quasi-ordered set is in W+W^+. We do not know, however if the class of well quasi-ordered sets is contained in W+W^+. Additional results concern homomorphic images of posets algebras.

Keywords

Cite

@article{arxiv.math/0702585,
  title  = {Poset algebras over well quasi-ordered posets},
  author = {Uri Abraham and Robert Bonnet and Wieslaw Kubis},
  journal= {arXiv preprint arXiv:math/0702585},
  year   = {2012}
}

Comments

28 pages

R2 v1 2026-07-22T17:51:23.744Z