dc.contributor.author | Boney, Will | |
dc.contributor.author | Csima, Barbara F. | |
dc.contributor.author | Day, Nancy A. | |
dc.contributor.author | Harrison-Trainor, Matthew | |
dc.date.accessioned | 2023-07-24 15:11:46 (GMT) | |
dc.date.available | 2023-07-24 15:11:46 (GMT) | |
dc.date.issued | 2023-03-15 | |
dc.identifier.uri | https://doi.org/10.1017/bsl.2023.1 | |
dc.identifier.uri | http://hdl.handle.net/10012/19630 | |
dc.description | © The Author(s), 2023. Published by Cambridge University Press on behalf of The Association for Symbolic Logic. | en |
dc.description.abstract | When classes of structures are not first-order definable, we might still try to find a nice description. There are two common ways for doing this. One is to expand the language, leading to notions of pseudo-elementary classes, and the other is to allow infinite conjuncts and disjuncts. In this paper we examine the intersection. Namely, we address the question: Which classes of structures are both pseudo elementary and Lω1,ω-elementary? We find that these are exactly the classes that can be defined by an infinitary formula that has no infinitary disjunctions. | en |
dc.language.iso | en | en |
dc.publisher | Cambridge University Press | en |
dc.relation.ispartofseries | Bulletin of Symbolic Logic; | |
dc.rights | Attribution 4.0 International | * |
dc.rights.uri | http://creativecommons.org/licenses/by/4.0/ | * |
dc.subject | extensions of first order logic | en |
dc.subject | infinitarily definable classes | en |
dc.subject | pseudo-elementary classes | en |
dc.subject | infinitary logic | en |
dc.title | Which Classes of Structures are Both Pseudo-Elementary and Definable by an Infinitary Sentence | en |
dc.type | Article | en |
dcterms.bibliographicCitation | BONEY, W., CSIMA, B., DAY, N., & HARRISON-TRAINOR, M. (2023). WHICH CLASSES OF STRUCTURES ARE BOTH PSEUDO-ELEMENTARY AND DEFINABLE BY AN INFINITARY SENTENCE? Bulletin of Symbolic Logic, 29(1), 1-18. doi:10.1017/bsl.2023.1 | en |
uws.contributor.affiliation1 | Faculty of Mathematics | en |
uws.contributor.affiliation2 | David R. Cheriton School of Computer Science | en |
uws.typeOfResource | Text | en |
uws.peerReviewStatus | Reviewed | en |
uws.scholarLevel | Faculty | en |