Joachim's web pages [Home] [Math]

Talks 1999-2021

2021-04-08 The Topos Institute Colloquium Noncrossing hyperchords and free probability
2021-03-09 Toulouse Petri nets and processes
2020-12-02 UNAM (Mexico) Whole-grain Petri nets and processes
2020-11-25 Western U. Decomposition spaces, incidence algebras and Möbius inversion
2020-11-24 Algebra Colloquium, Augsburg Decomposition spaces, incidence algebras and Möbius inversion
2020-11-12 U. Virginia Homotopy combinatorics and homotopy linear algebra
2020-11-06 Carnegie Mellon U. Decomposition spaces, incidence algebras and Möbius inversion
2020-07-06 International Applied Category Theory Conference ACT2020 Whole-grain Petri nets and processes (keynote presentation) [video recording]
2020-05-21 TallCat (Tallinn) Whole-grain Petri nets and processes
2020-04-16 MIT Categories Seminar The incidence comodule bialgebra of the Baez-Dolan construction
2020-04-01 Algebraic and Combinatorial Perspectives in the Mathematical Sciences Simplicial objects and combinatorial bialgebras
2020-03-12 Montpellier Infinity-operads as polynomial monads
2020-02-21 Mathematical Pearls (Trondheim) Möbius inversion — from number theory to renormalisation
2020-02-17 Trondheim Objective Combinatorics and Decomposition Spaces II
2020-02-10 Trondheim Objective Combinatorics and Decomposition Spaces I [Abstract]
2019-07-13 International Category Theory Conference 2019 (Edinburgh) Operadic categories, decalage, and decomposition spaces [Abstract]
2019-06-17 Trondheim Infinity-operads as polynomial monads
3-7 June 2019 CRM Advanced course: Combinatorics of decomposition spaces
2019-05-24 Current directions in homotopical algebra (Pohang) Operadic categories and 2-Segal spaces [Abstract]
2019-05-07 Kolloquium über reine Mathematik (Hamburg) Combinatorial Dyson-Schwinger equations, polynomial functors, and inductive types [Abstract]
2019-05-07 Hamburg Polynomial functors
2019-04-29 UB Introduction to type theory
2019-04-25 Nice Point-free topology and Hochster duality in derived categories
2019-04-04 HoTTEST Infinity-operads as polynomial monads [Abstract]
2019-02-18 UB From sets and toposes to infinity groupoids and infinity toposes
2019-02-12 Lausanne Infinity-operads as polynomial monads
2019-01-31 Thomas Poguntke Memorial Workshop (Barcelona) Operadic categories and 2-Segal spaces
2018-12-05 Torino From Möbius inversion to renormalisation [Abstract]
2018-11-14 CDR Renormalisation (Clermont-Ferrand) The incidence comodule bialgebra of the Baez-Dolan construction [Abstract]
2018-07-14 International Category Theory Conference 2018 (Ponta Delgada) Infinity-operads as polynomial monads [Abstract]
2018-06-14 Structures in local quantum field theory (Les Houches) Polynomial functors and combinatorial Dyson-Schwinger equations
2017-09-29 Categories for homotopy theory and rewriting (Luminy) Infinity-operads as polynomial monads [Abstract]
2017-09-22 UAB Topology Seminar Infinity-operads as polynomial monads
2017-09-05 OASIS: The Oxford Advanced Seminar on Informatic Structures Infinity-operads as polynomial monads [Abstract]
2017-06-30 Homotopical Methods in Algebra, Geometry and Topology (Malaga) Infinity-operads as polynomial monads
2017-06-16 UAB Topology Seminar Combinatorial Dyson-Schwinger equations and polynomial functors
2017-05-08 Aarhus Combinatorial Dyson-Schwinger equations and polynomial functors [Abstract]
2017-05-08 Aarhus (QGM) Point-free topology and Hochster duality in derived categories [Abstract]
2017-05-02 Copenhagen Decomposition spaces, incidence algebras, and Möbius inversion [Abstract]
2016-06-25 Higher-Dimensional Rewriting and Applications (Porto) Open graphs and hypergraphs
2016-06-02 Paris XIII Faa di Bruno for operads and internal algebras
2016-05-22 PSSL100 (Cambridge) Faa di Bruno for operads [Abstract]
2016-05-13 UAB Topology Seminar Notions of support
2016-05-06 UAB Topology Seminar Pointfree topology
2016-04-21 Barcelona Spring 2016 Workshop on Number Theory and K-theory From zeta functions to Waldhausen's S-construction
2016-02-19 Max Planck Combinatorial Dyson-Schwinger equations, polynomial functors and inductive types
2016-01-27 Categories, Homotopy and Rewriting (Toulouse) Decomposition spaces, incidence algebras, and Möbius inversion [Abstract]
2015-12-07 Mathematical Physics Seminar (Berlin) Polynomial functors and combinatorial Dyson-Schwinger equations [Abstract]
2015-09-10 Category Theory and Algebraic Topology (Louvain-la-neuve) From quasitoposes to infinity quasitoposes [Abstract]
2015-06-02 Stockholm Decomposition spaces, incidence algebras and Möbius inversion [Abstract]
2015-05-19 21st International Conference on Types for Proofs and Programs, TYPES 2015 (Tallinn) Polynomial functors: a general framework for induction and substitution [Abstract]
2015-05-07 YaMCATS (Leeds) Three lectures on polynomial functors [Abstract]
2015-04-21 Workshop on Brave New Algebra: opening perspectives (Barcelona) Point-free topology and Hochster duality in derived categories [Abstract]
2015-04-10 Homotopical Algebra and Geometry (Lancaster) Rudiments of Homotopy Combinatorics [Abstract]
2015-03-25 Australian Category Seminar Schmitt's restriction species, and a related general construction of decomposition spaces
2015-03-18 Australian Category Seminar Decomposition spaces and incidence algebras
2015-03-11 Australian Category Seminar Graphs, hypergraphs and properads, part 2
2015-03-04 Australian Category Seminar Graphs, hypergraphs and properads
2015-02-25 Australian Category Seminar Joyal theorems for homotopical species
2015-01-13 Tropical Seminar Valuations, supports, point-free topology, and constructive algebraic geometry
2014-10-12 PSSL96 (Palermo) Point-free topology and Hochster duality in derived categories [Abstract]
2014-09-26 Dyson-Schwinger Equations in Modern Mathematics & Physics (ECT*, Trento) Polynomial fixpoint equations and bialgebras of inductive datatypes [Abstract]
2014-07-15 Homotopical Algebra Summer Days (Barcelona) Graphs, hypergraphs, and properads [Abstract]
2014-07-01 International Category Theory Conference 2014 (Cambridge) Decomposition spaces, incidence algebras and Möbius inversion [Abstract]
2014-06-04 Workshop on constructive mathematics and models of type theory (Paris) Univalence in locally cartesian closed infinity-categories [Abstract]
2014-05-20 Journées de la Fédération de recherche en mathématiques de Paris-Centre Combinatorial Dyson-Schwinger equations, polynomial functors, and operads of Feynman graphs [Abstract]
2014-05-06 UFPE (Recife) Polynomial functors, infinity-groupoids, and homotopy type theory II
2014-04-24 UFPE (Recife) Polynomial functors, infinity-groupoids, and homotopy type theory I
2013-11-28 Workshop on Algebraic and Geometric Combinatorics (Madrid) Decomposition spaces, incidence algebras, and Moebius inversion [Abstract]
2013-06-07 CMS Summer Meeting, special session on higher categories (Halifax, Canada) Incidence algebras and Moebius inversion in Rezk categories and decomposition spaces [Abstract]
2013-06-01 Foundational Methods in Computer Science (Mount Allison, Canada) Polynomial functors over groupoids: from program semantics to quantum field theory -- and back (two lectures) [Abstract]
2013-05-02 Nice Polynomial Functors over Groupoids: from Program Semantics to Quantum Field Theory [Abstract]
2013-03-21 Mathematical Physics Seminar, ETH Zürich Polynomial functors over groupoids, and combinatorial Dyson-Schwinger equations [Abstract]
2013-03-01 UAB Topology Seminar Homotopy Type Theory II: Inductive and higher inductive types
2013-02-25 Institute for Advanced Study, Princeton Joyal Theorems for Homotopical Species
2013-02-21 Institute for Advanced Study, Princeton Locally cartesian closed infinity categories II
2013-02-18 Institute for Advanced Study, Princeton Locally cartesian closed infinity categories I
2013-02-11 UB Infinity toposes: Giraud axioms and object classifiers
2013-02-01 UAB Topology Seminar Homotopy Type Theory I: Overview and syntax
2012-11-23 ICMAT, Madrid Möbius inversion in general categories [Abstract]
2012-10-19 UAB Topology Seminar Data types with symmetries and polynomial functors over groupoids
2012-10-12 Mathematical Aspects of Hadron Physics (ECT*, Trento) Groupoids and polynomial functors in the combinatorics of Quantum Field Theory [Abstract]
2012-06-21 Nice Groupoids, and Faa di Bruno formulae for Green functions in bialgebras of trees [Abstract]
2012-06-06 28th Conference on the Mathematical Foundations of Programming Semantics (Bath) Data types with symmetries and polynomial functors over groupoids [Abstract] [Conference paper]
2012-05-11 Regensburg Faà di Bruno formulae for Green functions in bialgebras of trees [Abstract]
2012-02-13 Tropical Tutte polynomial survey, part 2: graph colouring and Potts model
2012-02-08 Paris VII Théories topologiques de champs de dimension 2 et algèbres de Frobenius — once again
2012-02-07 Paris VII Groupoids, and Faà di Bruno formulae for Green functions in bialgebras of trees [Abstract]
2012-01-30 Tropical Tutte polynomial, Whitney 2-isomorphism, and survey
2011-10-07 UAB Topology Seminar Symmetries of graphs and trees [Abstract]
2011-07-08 UAB Topology Seminar Homotopical species
2011-06-02 Algebra and Combinatorics Seminar Balmer's spectrum is Hochster dual to the Zariski spectrum
2011-04-05 UB From sets and toposes to infinity groupoids and infinity toposes
2011-03-31 Algebra and Combinatorics Seminar Spectra and supports
2011-02-08 Regensburg Categories of Feynman graphs --- from modular operads to quantum field theory
2011-02-03 Centenario de la R.S.M.E. (Ávila) Categories of graphs and trees [Abstract]
2010-11-18 Algebra and Combinatorics Seminar Connes-Kreimer Hopf algebra and renormalisation
2010-11-11 Algebra and Combinatorics Seminar Incidence Hopf algebras [Notes for part 1]
2010-10-14 Feynman graphs (Clermont-Ferrand) Categories of graphs and trees [Abstract]
2010-06-24 CT2010 (Genova) Categorification of Hopf algebras of rooted trees [Abstract]
2010-03-18 DFT Zaragoza Feynman graphs and compact symmetric multicategories
2010-03-15 Tropical Classical examples of commutative monads II: linear algebra, affine geometry, convex geometry, semi-lattices, etc.
2010-03-12 Homotopical methods in geometry and algebra (Sevilla) Joyal theorems for homotopical species [Abstract]
2010-03-01 Tropical Classical examples of commutative monads I: linear algebra from the viewpoint of operads, monads, and Lawvere theories
19-23 Oct. 2009 Advanced Course on TQFTs (Almería) Frobenius algebras and 2D topological quantum field theories (four lectures)
12-14 Aug. 2009 2nd Seminar on Category Theory and Applications (Santa Marta, Colombia) Minicourse on polynomial functors (three lectures)
2009-08-10 Bogotá Topological quantum field theories and Fibonacci sequences
2009-07-03 B-Top Feynman graphs and modular operads
2009-05-08 UAB Baez-Dolan construction and stable opetopes
2009-04-30 Opérades 2009 (Luminy) Feynman graphs, and nerve theorem for modular operads [Abstract]
2009-04-08 Quantum Physics and Logic VI (Oxford) Feynman graphs and compact multicategories [Abstract]
2009-04-06 Leicester Feynman graphs, and nerve theorem for modular operads
2009-03-20 UAB Globular operads and weak omega-categories 2
2009-03-13 UAB Globular operads and weak omega-categories 1
2009-02-13 B-Top The sugar-free Deligne conjecture (no little-discs, no braces, differentials or signs)
2009-01-29 Chambéry Introduction to the theory of polynomial functors (with emphasis on applications to logic) [Abstract]
2008-11-07 B-Top Stasheff operad and Boardman-Vogt resolution
2008-09-03 CATS3: Higher categorical structures in algebraic geometry (Pisa) Feynman graphs, and nerve theorem for modular operads [Abstract]
2008-06-03 Utrecht Polynomial functors and trees
2008-04-19 Higher Operads Week Combinatorics of opetopes [Abstract]
2008-03-22 PSSL87 (Patras) Polynomial functors and trees [Abstract]
2008-02-04 CRM: Advanced course Formal construction of Moerdijk and Weiss's Ω
2007-11-28 CRM Polynomial functors and trees (continued)
2007-11-19 CRM Polynomial functors and trees
2007-10-29 CRM Prime spectrum and supports of a tensor triangulated category, according to Balmer
2007-09-27 CRM Topological quantum field theories and Fibonacci sequences
2007-06-06 SECA4 Algebraic geometry over symmetric monoidal categories (after Toën and Vaquié) [Abstract]
2007-05-25 B-Top Polynomial functors, trees, and coloured operads
2007-03-24 PSSL85 (Nice) Polynomial functors and trees [Abstract]
2007-03-12 Tropical Riemann-Roch for finite graphs
2007-03-01 UAB: Sheaves sem. Stacks (introduction to ~, in one hour)
2007-01-12 B-Top Infinity-1-categories: overview
2007-01-11 Singular meeting (Barcelona) Counting curves via lattice paths (after Mikhalkin)
2006-12-20 UB Factorisation systems
2006-12-13 UB The classical theory of monads
2006-10-26 TTT57 (Leicester) Polynomial functors, trees, and opetopes [Abstract]
2006-07-21 Barcelona Topology Workshop 2006 Commutativity in double semigroups and two-fold monoidal categories [Abstract]
2006-05-12 B-Top Brave new Gorenstein algebras
2006-04-05 CRM Study group on cross functors: Cross functors
2006-03-15 CRM Study group on cross functors: The language of 2-categories
2006-03-13 Tropical Semi-rings and Zariski categories
2006-02-27 Tropical Introduction to Zariski categories
2006-02-02 B-Top Morita theory for torsion and complete modules
2006-01-24 UB K-theory and simplicial localisation
2006-01-13 UB-AlgGeom Polynomial functors, negative sets, and moduli of punctured Riemann spheres [Abstract]
2005-12-19 Tropical Base change for schemes under Spec(Z) (part 2)
2005-12-12 Tropical Base change for schemes under Spec(Z)
2005-11-10 B-Top Matlis duality (part 2)
2005-11-03 B-Top Matlis duality
2005-07-21 StreetFest (Sydney/Canberra) Weak units and homotopy 3-types [Abstract]
2005-06-29 Tropical Numbers of tropical plane curves through points in general position
2005-06-16 B-Top Weak units and homotopy 3-types
2005-04-27 Tropical The Legendre transform
2005-04-06 Tropical Tropical enumerative geometry (part 2)
2005-03-29 Tropical Tropical enumerative geometry
2005-02-25 UB-AlgGeom Quantum cohomology and characteristic numbers [Abstract]
2004-11-11 CIRGET Junior Polynomial functors
2004-11-02 CTRC Seminar (McGill) On the notion of unit in monoidal categories and monoidal 2-categories [Abstract]
2004-10-16 Categories Oktoberfest (Montréal) Weak units and realisation of homotopy 3-types [Abstract]
2004-06-16 IMA 2004 Summer Program on n-Categories: Foundations and Applications (Minneapolis) Topological quantum field theories
2004-06-02 CIRGET Junior Topological quantum field theories II
2004-05-26 CIRGET Junior Topological quantum field theories I
2004-02-26 CIRGET Junior Géométrie énumerative et théorie d'intersection II
2004-02-20 Séminaire CIRGET Quantum cohomology and characteristic numbers
2004-02-19 CIRGET Junior Géométrie énumerative et théorie d'intersection I
2003-07-24 Workshop on Categorification and Higher-Order Geometry (Lisbon) Weak identity arrows in higher categories [Abstract]
2003-05 CATS2: Higher categorical structures in algebraic geometry (Nice) A notion of weak identity arrows in higher categories [Abstract]
2003-04-09 Algebra Seminar (Aarhus) Weak identity arrows in higher categories
2003-03-20 Séminaire de Géométrie Algébrique (Nice) Weak identity arrows in higher categories
2002-10 Porto A fórmula de Kontsevich para curvas racionais planas - uma introdução à cohomologia quântica (minicourse, 4 lectures)
2002-09-25 School and conference on intersection theory and moduli (ICTP, Trieste) Tangency quantum cohomology
2002-07-18 Workshop on Frobenius manifolds, quantum cohomology, and singularities, in honour of Yu. I. Manin's 65th birthday (MPI, Bonn) Tangency quantum cohomology
2002-03-07 Séminaire de Géométrie Algébrique (Nice) Le nombre de coniques 5-fois tangentes à une courbe plane générique (d'après A. Gathmann) [Slides (not used)]
2002-01 UFPE Summer School (Recife) Minicourse (7 lectures): Frobenius algebras and 2D topological quantum field theories
2001-01-25 Séminaire de Géométrie Algébrique (Nice) Tangency quantum cohomology
2000-07-11 Workshop on artinian Gorenstein rings and Frobenius algebras (KTH, Stockholm) Introduction to formal Frobenius manifolds
2000-05-28 NORDAG meeting in Algebraic Geometry (Stockholm) Tangency quantum cohomology [Abstract]
2000-05-22 Algebraic Geometry Seminar (Oslo) Tangency quantum cohomology
2000-05-15 Seminar on Gromov-Witten theory (KTH, Stockholm) The virtual class of the space of conics having sixth order contact with a plane curve
2000-05-10 Seminar on Gromov-Witten theory (KTH, Stockholm) On Gathmann's paper Absolute and relative Gromov-Witten invariants of very ample hypersurfaces (Part 3)
2000-05-08 Seminar on Gromov-Witten theory (KTH, Stockholm) On Gathmann's paper Absolute and relative Gromov-Witten invariants of very ample hypersurfaces (Part 2)
2000-05-03 Seminar on Gromov-Witten theory (KTH, Stockholm) On Gathmann's paper Absolute and relative Gromov-Witten invariants of very ample hypersurfaces (Part 1)
2000-05-02 Seminar on Gromov-Witten theory (KTH, Stockholm) Gromov-Witten potential, generating functions and differential equations
2000-04-17 Seminar on Gromov-Witten theory (KTH, Stockholm) Topological recursion (genus zero)
2000-04-10 Seminar on Gromov-Witten theory (KTH, Stockholm) Psi classes and gravitational descendants
1999-07 ALGA III: Algebra Comutativa e Geometria Algébrica (UNICAMP, Campinas) Enumeratively well-behaved divisor classes on the space of stable maps
1999-07 22º Colóquio Brasileiro de Matemática (IMPA, Rio de Janeiro) Kontsevich’s formula for rational plane curves (5 lectures, with Israel Vainsencher)
1999-03-24 Géométrie Algébrique en Liberté VII (Luminy) Counting bitangents of a smooth plane curve via stable maps


Last updated: 2025-09-28.