Profinite Structures are Retracts of Ultraproducts of Finite Structures
| dc.creator | Mariano, Hugo Luiz | |
| dc.date | 2004-01-09 | |
| dc.date.accessioned | 2026-07-07T05:04:28Z | |
| dc.date.available | 2026-07-07T05:04:28Z | |
| dc.description | We establish the following model-theoretic characterization: profinite $L$-structures, the cofiltered limits of finite $L$-structures,are retracts of ultraproducts of finite $L$-structures. As a consequence, any elementary class of $L$-structures axiomatized by $L$-sentences of the form $\forall \vec{x} (ψ_{0}(\vec{x}) \ra ψ_{1}(\vec{x}))$, where $ψ_{0}(\vec{x}),ψ_{1}(\vec{x})$ are existencial-positives $L$-formulas, is closed under the formation of profinite objects in the category {\bf L-mod}, the category of structures suitable for the language $L$ and $L$-homomorphisms. | |
| dc.identifier | https://arxiv.org/abs/math/0401095 | |
| dc.identifier | http://arxiv.org/abs/math/0401095 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/69813 | |
| dc.subject | Logic | |
| dc.subject | Category Theory | |
| dc.subject | 03C20, 03C30 | |
| dc.title | Profinite Structures are Retracts of Ultraproducts of Finite Structures | |
| dc.type | text |