A counterexample to the reconstruction of ω-categorical structures from their endomorphism monoid

Publikation: Beitrag in FachzeitschriftForschungsartikelBeigetragenBegutachtung

Beitragende

  • Manuel Bodirsky - , Institut für Algebra, Technische Universität Dresden (Autor:in)
  • David Evans - , Imperial College London (Autor:in)
  • Michael Kompatscher - , Technische Universitat Wien (Autor:in)
  • Michael Pinsker - , Technische Universitat Wien, Karlsuniversität Prag (Autor:in)

Abstract

We present an example of two countable ω-categorical structures, one of which has a finite relational language, whose endomorphism monoids are isomorphic as abstract monoids, but not as topological monoids—in other words, no isomorphism between these monoids is a homeomorphism. For the same two structures, the automorphism groups and polymorphism clones are isomorphic, but not topologically isomorphic. In particular, there exists a countable ω-categorical structure in a finite relational language which can neither be reconstructed up to first-order biinterpretations from its automorphism group, nor up to existential positive bi-interpretations from its endomorphism monoid, nor up to primitive positive bi-interpretations from its polymorphism clone.

Details

OriginalspracheEnglisch
Seiten (von - bis)57-82
Seitenumfang26
FachzeitschriftIsrael journal of mathematics
Jahrgang224
Ausgabenummer1
PublikationsstatusVeröffentlicht - 1 Apr. 2018
Peer-Review-StatusJa

Externe IDs

ORCID /0000-0001-8228-3611/work/142241084

Schlagworte

ASJC Scopus Sachgebiete