Abstract
A Boolean algebraB that has a well-founded sublattice which generatesB is called awell-generated Boolean algebra. Every well-generated Boolean algebra is superatomic. However, there are superatomic algebras which are not well-generated. We consider two types of increasing chains of Boolean algebras, canonical chains and rank preserving chains, and show that the class of well-generated Boolean algebras is not closed under union of such chains, even when these chains are taken to be countable. A Boolean algebra issuperatomic iff its Stone space is scattered. IfB is superatomic anda∈B, then therank ofa is the Cantor Bendixon rank of the Stone space of{b‖b≤a}. A chain {B α‖α<δ} is acanonical chain if for every α<β<δ,B αis the subagebra ofB βgenerated by all members ofB βwhose rank is <α. For a superatomic algebraB, I(B) denotes the ideal consisting of all members ofB whose rank is less than the rank ofB. A chain {B α‖α<δ} is arank preserving chain if for every α<β<δ anda∈I(Bα), the rank and mutiplicity ofa inB αare equal to the rank and mutiplicity ofa inB β.
Similar content being viewed by others
References
[BR1] R. Bonnet and M. Rubin,On well generated Boolean algebras, Annals of Pure and Applied Logic105 (2000), 1–50.
[BR2] R. Bonnet and M. Rubin,On a poset algebra which is hereditarily but not canonically well generated, Israel Journal of Mathematics135 (2003), 299–326.
[DS] A. Dow and P. Simon,Thin-tall Boolean algebras and their automorphism groups, Algebra Universalis29 (1992), 211–226.
[KV] K. Kunen and J. E. Vaughan,Handbook of Set-Theoretic Topology, North-Holland, Amsterdam, 1984.
Author information
Authors and Affiliations
Additional information
Supported by The Center For Advanced Studies in Mathematics “Ben Gurion University”.
Rights and permissions
About this article
Cite this article
Bonnet, R., Rubin, M. Chains of well-generated Boolean algebras whose union is not well-generated. Isr. J. Math. 154, 141–155 (2006). https://doi.org/10.1007/BF02773602
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF02773602