A Roadmap to Decidability

It is well known that quantifier elimination plays a relevant role in proving decidability of theories. Herein the objective is to provide a toolbox that makes it easier to establish quantifier elimination in a semantic way, capitalizing on the fact that a 1-model-complete theory with algebraically prime models has quantifier elimination. Iteration and adjunction are identified as important constructions that can be very helpful, by themselves or composed, in proving that a theory has algebraically prime models. Some guidelines are also discussed towards showing that a theory is 1-model-complete. Illustrations are provided for the theories of the natural numbers with successor, term algebras (having stacks as a particular case) and algebraically closed fields.

[1]  K. Gödel Über formal unentscheidbare Sätze der Principia Mathematica und verwandter Systeme I , 1931 .

[2]  K. Gödel Über formal unentscheidbare Sätze der Principia Mathematica und verwandter Systeme I , 1931 .

[3]  R. Tennant Algebra , 1941, Nature.

[4]  A. Tarski A Decision Method for Elementary Algebra and Geometry , 2023 .

[5]  Herbert B. Enderton,et al.  A mathematical introduction to logic , 1972 .

[6]  M. Karoubi K-Theory: An Introduction , 1978 .

[7]  K. Brown,et al.  Graduate Texts in Mathematics , 1982 .

[8]  W. J. Thron,et al.  Encyclopedia of Mathematics and its Applications. , 1982 .

[9]  Ronald Fagin,et al.  A logic for reasoning about probabilities , 1988, [1988] Proceedings. Third Annual Information Symposium on Logic in Computer Science.

[10]  Wilfrid Hodges,et al.  Model Theory: The existential case , 1993 .

[11]  Volker Weispfenning,et al.  Simulation and Optimization by Quantifier Elimination , 1997, J. Symb. Comput..

[12]  D. Marker Model theory : an introduction , 2002 .

[13]  David Delahaye,et al.  Quantifier Elimination over Algebraically Closed Fields in a Proof Assistant using a Computer Algebra System , 2005, Calculemus.

[14]  Dov M. Gabbay,et al.  Second-Order Quantifier Elimination in Higher-Order Contexts with Applications to the Semantical Analysis of Conditionals , 2007, Stud Logica.

[15]  Tobias Nipkow Linear Quantifier Elimination , 2008, IJCAR.

[16]  André Platzer,et al.  Differential-algebraic Dynamic Logic for Differential-algebraic Programs , 2010, J. Log. Comput..

[17]  David Monniaux,et al.  Quantifier Elimination by Lazy Model Enumeration , 2010, CAV.

[18]  Ashish Tiwari,et al.  Verification and synthesis using real quantifier elimination , 2011, ISSAC '11.

[19]  Eric Walter From Calculus to Computation , 2014 .