2021/01/07 by Gorman, Alexi Block, Caulfield, Erin, Hieronymi, Philipp
#03C64 #FOS: Mathematics #Logic (math.LO)
paper · doi:10.48550/arxiv.2101.02651
This paper answers several open questions around structures with o-minimal open core. We construct an expansion of an o-minimal structure R by a unary predicate such that its open core is a proper o-minimal expansion of R. We give an example of a structure that has an o-minimal open core and the exchange property, yet defines a function whose graph is dense. Finally, we produce an example of a structure that has an o-minimal open core and definable Skolem functions, but is not o-minimal.