Algebra|Coalgebra Seminar

[News & Future Meetings]  [Previous Meetings]   [Contact]  

This page concerns the Algebra|Coalgebra Seminar at the Institute for Logic, Language & Computation (ILLC) of the University of Amsterdam. The purpose of the seminar is to disseminate results and insights about and around algebraic and coalgebraic methods in logic.

News & Future meetings

    Speaker: George Metcalfe (Universität Bern)

    Title: Ordering Free Groups

    Coordinates: Wednesday, 26 April, 2017 at 16:00 in room F1.15, Science Park 107, Amsterdam.


    Ordering conditions for groups provide useful tools for the study of various relationships between group theory, universal algebra, topology, and logic. In this talk, I will describe a new “algorithmic” ordering condition for extending partial orders on groups to total orders. I will then show how this condition can be used to show that extending a finite subset of a free group to a total order corresponds to checking validity of a certain inequation in the class of totally ordered groups. As a direct consequence, we obtain a new proof that free groups are orderable.

    Speaker: Nick Bezhanishvili (ILLC)

    Title: TBA

    Coordinates: Wednesday, 10 May, 2017 at 16:00 in room F1.15, Science Park 107, Amsterdam.

Previous Meetings

  • Title: Modal logics of the real line
    Speaker: Andrey Kudinov (HSE Moscow)
    Date: Wednesday, 14 December.

  • Title: Nominal Sets in Constructive Set Theorys
    Speaker: Andrew Swan (ILLC)
    Date: Wednesday, 9 November.

  • Title: Some model theory for the modal mu-calculus
    Speaker: Yde Venema (ILLC)
    Date: Wednesday, 26 October.

  • Title: On generalized Van-Benthem-type characterizations
    Speaker: Grigory Olkhovikov (Ruhr-Universitaet Bochum, Institut fuer Philosophie II)
    Date: Wednesday, 28 September.

  • Title: Bitopology and four-valued logic
    Speaker: Tomáš Jakl (Charles University, Prague and University of Birmingham)
    Date: Wednesday, 4 May, 2016.

  • Title: MV-algebras and the Pierce-Birkhoff conjecture
    Speaker: Serafina Lapenta (University of Salerno)
    Date: Wednesday, 20 April, 2016.

  • Title: Studying profinite semigroups via logic
    Speaker: Sam van Gool (CUNY City College and ILLC)
    Date: Wednesday, 30 March, 2016.

  • Title: Investigations on Gödel’s incompleteness properties for guarded fragment and other decidable versions of FOL
    Speaker: Mohamed Khaled (Central European University, Budapest)
    Date: Wednesday, 16 March, 2016.

  • Title: Subminimal Logics of Negation
    Speaker: Almudena Colacito (ILLC)
    Date: Wednesday, 9 March, 2016.

  • Title: Weak Subintuitionistic Logic
    Speaker: Fatemeh Shirmohammadzadeh Maleki (Shahid Beheshti University, Tehran and ILLC)
    Date: Wednesday, 24 February, 2016.

  • Title: Monadic second order logic as the model companion of temporal logic
    Speaker: Silvio Ghilardi (University of Milan)
    Date: Wednesday, 27 January, 2016.

  • Title: Duality for Non-monotonic Consequence Relations and Antimatroids
    Speakers: Joahnnes Marti and Riccardo Pinosio (ILLC)
    Date: Wednesday, 2 December, 2015.

  • Title: Some open problems concerning MSO for coalgebras
    Speaker: Sebastian Enqvist (ILLC)
    Date: Wednesday, 18 November, 2015.

  • Title: Derivative and counting operators on topological spaces
    Speaker: Alberto Gatto (Imperial College London)
    Date: Wednesday, 18 November, 2015.

  • Title: Coalgebraic many-valued logics
    Speaker: Marta Bílková (Charles University in Prague)
    Date: Wednesday, 4 November, 2015.

  • Title: The Wellfounded Parts of Final Coalgebras are Initial Algebras
    Speaker: Larry Moss (Indiana University Logic Program and Math department)
    Date: Wednesday, 8 July, 2015.

  • Title: Stable canonical rules: bounded proofs, dichotomy property and admissible bases
    Speaker: Silvio Ghilardi (University of Milan)
    Date: Wednesday, 27 May, 2015.

  • Title: Stone duality above dimension zero
    Speaker: Vincenzo Marra (University of Milan)
    Date: Wednesday, 27 April, 2015.

  • Title: Modal logic of topology
    Speaker: Nick Bezhanishvili (ILLC) and Jan van Mill (KdVI)
    Date: Wednesday, 15 April, 2015.

  • Title: Global caching for the alternation-free coalgebraic mu-calculus
    Speaker: Daniel Hausmann (Friedrich-Alexander University of Erlangen and Nurnberg)
    Date: Wednesday, 1 April, 2015.

  • Title: Dependency as question entailment
    Speaker: Ivano Ciardelli (ILLC, University of Amsterdam)
    Date: Wednesday, 18 March, 2015.

  • Title: Up-to techniques for bisimulations with silent moves
    Speaker: Daniela Petrişan (Raboud University, Nijmegen)
    Date: Wednesday, 4 March, 2015.

  • Title: Strong Completeness for Iteration-free Coalgebraic Dynamic Logics.
    Speaker: Helle Hansen (TU Delft)
    Date: Wednesday, 18 February, 2015.

  • Title: Residuated Basic Algebras
    Speaker: Minghui Ma (Southwest University)
    Date: Wednesday, 4 February, 2015.

  • Title: Non-self-referential realizable frangments of modal and intuitionistic logics
    Speaker: Junhua Yu (Tsinghua University)
    Date: Wednesday, 21 January, 2015.

  • Title: Modal Logics for Presheaf Categories
    Speaker: Giovanni Cina (ILLC, University of Amsterdam)
    Date: Wednesday, 3 December, 2014.

  • Title: Completeness and Incompleteness in Nominal Kleene Algebra
    Speaker: Dexter Kozen (Cornell University)
    Date: Wednesday, 26 November, 2014.

  • Title: Polyhedra: from geometry to logic
    Speaker: Andrea Pedrini (University of Milan)
    Date: Wednesday, 5 November, 2014.

  • Title: Exact Unification Type and Admissible rules
    Speaker: Leonardo Cabrer (University of Florence, Italy)
    Date: Wednesday, 29 October, 2014.

  • Title: PDL has Craig Interpolation since 1981
    Speaker: Malvin Gattinger (ILLC, University of Amsterdam)
    Date: Wednesday, 1 October, 2014.

  • Title: Changing a Semantics: Opportunism, or Courage?
    Speaker: Johan van Benthem (ILLC, University of Amsterdam)
    Date: Wednesday, 17 September, 2014.

  • Title: Axiomatizations of intermediate logics via the pseudo-complemented lattice reduct of Heyting algebras
    Speaker: Julia Ilin (ILLC, University of Amsterdam)
    Date: Wednesday, 11 June, 2014.

  • Title: Duality and canonicity for Boolean algebra with a relation
    Speaker: Sumit Sourabh (ILLC, University of Amsterdam)
    Date: Wednesday, 11 June, 2014.

  • Title: Adding the Supremum to Interpretability Logic
    Speaker: Paula Henk (ILLC, University of Amsterdam)
    Date: Wednesday, 28 May, 2014.

  • Title: Duality for Logic of Quantum Actions
    Speaker: Shengyang Zhong (ILLC, University of Amsterdam)
    Date: Wednesday, 28 May, 2014.

  • Title: Many-valued modal logic over residuated lattices via duality (joint work with Andrew Craig - University of Johannesburg)
    Speaker: Umberto Rivieccio (Delft University of Technology)
    Date: Wednesday, 14 May, 2014.

  • Title:Using Admissible Rules to Characterise Logics
    Speaker: Jeroen Goudsmit (Utrecht University)
    Date: Wednesday, 30 April, 2014.

  • Title:Uniform Interpolation for Coalgebraic Fixpoint Logic
    Speaker: Fatemeh Seifan (ILLC, University of Amsterdam)
    Date: Wednesday, 30 April, 2014.

  • Title:Free algebras for Gödel-Löb provability logic
    Speaker: Sam van Gool (LIAFA, Université Paris-Diderot & Radboud Universiteit Nijmegen)
    Date: Wednesday, 16 April, 2014.

  • Title: Canonical rules for modal logic
    Speaker: Nick Bezhanishvili (ILLC, University of Amsterdam)
    Date: Thursday, 20 March, 2014.

  • Title: From free algebras to proof bounds.
    Speaker: Silvio Ghilardi (University of Milano)
    Date: Thursday, 20 February, 2014.

  • Title: Cut-elimination in circular proofs.
    Speaker: Jérôme Fortier (UQAM / AMU)
    Date: Thursday, 20 February, 2014.

  • Title: Open maps, small maps and final coalgebras.
    Speaker: Benno van den Berg (ILLC, University of Amsterdam)
    Date: Thursday, 6 February, 2014.

  • Title: A coalgebraic view of characteristic formulas in equational modal fixed point logics.
    Speaker: Sebastian Enqvist (ILLC, University of Amsterdam)
    Date: Wednesday, 22 January, 2014.

  • Title: Coalgebriac Announcement Logics
    Speaker: Facundo Carreiro (ILLC, University of Amsterdam)
    Date: Wednesday, 4 December, 2013.

  • Title: An algebraic approach to cut-elimination for substructural logics.
    Speaker: Sumit Sourabh (ILLC, University of Amsterdam)
    Date: Wednesday, 20 November, 2013.

  • Title: Terminal Sequences and Their Coalgebras.
    Speaker: Johannes Marti (ILLC, University of Amsterdam)
    Date: Wednesday, 31 October, 2013.

  • Title: Two isomorphism criteria for directed colimits.
    Speaker: Luca Spada (ILLC, Amsterdam and University of Salerno)
    Date: Wednesday, 9 October, 2013.

  • Title: A non-commutative Priestly duality
    Speaker: Sam van Gool (Radbound University, Nijmegen)
    Date: Wednesday February 13, 2013

  • Title: Bilattices with modal operators
    Speaker: Speaker: Umberto Rivieccio (University of Birmingham)
    Date: Wednesday May 30, 2012

  • Title: Topological- and Neighborhood-Sheaf Semantics for First-Order Modal Logic
    Speaker: Kohei Kishida (ILLC, Amsterdam)
    Date: Wednesday May 23, 2012

    A|C seminar in 2009/2010
    A|C seminar in 2008/2009
    A|C seminar in 2007/2008
    A|C seminar in 2006/2007

  • Contact

    The seminar is currently organized by Julia Ilin, Nick Bezhanishvili, and Frederik Lauridsen. If you're interested in giving a talk at the seminar please contact Julia at ilin.juli[at] or Frederik at f.m.lauridsen[at]

    If you want to subscribe to the A|C seminar mailing list please send an email to Frederik at f.m.lauridsen[at] with the subject "A|C seminar".