2018 | September 2 - 8, Lukecin, school `Arithmetic of Differential Equations' |

| September 1 - December 1, Warsaw, program `Varieties: Arithmetic and Transformations` |

| May 28 - June 1, CIRM - Lumini, Algebra, Arithmetic and Combinatorics of Differential and Difference Equations |

| March 16, Dutch InterCity Seminar in Utrecht, talk 'Dwork crystals and related congruences' |

| January 3 - April 20, HIM Bonn, Periods in Number Theory, Algebraic Geometry and Physics, talk 'What is... a motivic gamma function'[notes] |

2017 |
October 1-6, BIRS, p-adic cohomology and arithmetic applications |

| July 1 - September 30, IHES |

| June 13-15, Universite Lyon 1 and ENS Lyon, talks 'p-adic unit-root formulas and Dwork cohomology' |

| January 8-28, Melbourne (Australia), program ` Hypergeometric motives and Calabi--Yau differential equations` |

2016 |
June 28 - July 1, Porquerolles (France), workshop on Automata, Algebraicity and G-functions [slides] |

| June 20-25, Herstmonceux Castle (East Sussex, UK), Calabi--Yau varieties: arithmetic, geometry and physics |

| June 1, UAM Poznan, Algebra, geometry and arithmetic seminar [slides] |

| May 23-28, IMJ-PRG Paris, Arithmetic L-functions and differential geometric methods (Regulators IV) |

| May 12-14, HU Berlin, Moduli and automorphic forms, talk 'Higher Hasse--Witt matrices' |

| April 20, University of Gdansk, Geometry Seminar, talk 'p-adic properties of periods' |

2015 |
November 24, University of Mainz, SFB Colloquium, talk 'Arithmetic properties of coefficients of logarithms of formal group laws' |

| November 10, Institute of Mathematics in Kyiv, Algebra Seminar, talk 'Arithmetic properties of formal groups' |

| October 23, IMPANGA, Warsaw |

| July 5-11, Oberwolfach, Explicit methods in number theory, talk 'Formal groups and congruences' |

| February 16-20, CRM of Montréal, Regulators, Mahler measures, and special values of L-functions, talk 'Explicit p-adic unit-root formulas for hypersurfaces' |

| January 14, MPIM Bonn, Seminar on recurrences and L-values |

2014 | November 10, University of Warwick, Number Theory Seminar, talk 'Dwork's congruences for periods of families of Calabi--Yau hypersurfaces' |

| September 1-12, ICTP Trieste, L-functions and modular forms
Notes of my course on Monski-Washnitzer cohomology and Kedlaya's algorithm for counting points on hyperelliptic curves over finite fields |

| August 18 - 22, MSRI Berkeley, New Geometric Methods in Number Theory |

| June 23-27, IHES Bures-sur-Yvette, Algebra, Geometry and Physics |

| April 3, Dublin Area Mathematics Colloquium, talk 'Counting points over finite fields on Calabi--Yau hypersurfaces' |

| March 29, UCD Algebra and Number Theory Seminar, talk 'Congruences for the constant terms of powers of a Laurent polynomial' |

2013 | July 14-20, Oberwolfach, Explicit methods in number theory, talk 'Determinantal differential operators with Frobenius structure' |

| July 10-12, Utrecht, Special functions and special numbers |

| June 15-20, Saariselkä, Arctic Number Theory Workshop, talk 'Dwork's congruences and p-adic overconvergence' |

| March 11-14, Dublin, 27th Automorphic Forms Workshop [slides] |

2012 | December 15-21, Bonn, Galois representations and pencils of Calabi--Yau motives, talk 'D3 equations and spectral elliptic curves' |

| November 5-9, Paris, Hypergeometric motives |

| August 26 - September 1, Oberwolfach, Low-dimensional topology and number theory |

| July 2-6, ICMAT Madrid, Periods and motives: a modern perspective on renormalization [slides] |

| June 25-29, ICTP Trieste, Hypergeometric motives |

| June 13-14, Irish Geometry Conference, University College Cork, talk 'Geometricity problem for differential equations' |

| May 29 - June 1, Paris, Hypergeometric series and their generalizations in algebra, geometry,
number theory and physics, talk 'Mahler's measure of a linear form and double L-values' |

| April 5, Dublin, K-Theory, Quadratic Forms and Number Theory seminar at UCD |

| March 23-28, MPIM Bonn, Motivic structures on quantum cohomology |

| February 27 - March 1, Cologne, Modular forms, mock theta functions, and applications [slides] |

2011 | July 17 - July 23, 2011, Oberwolfach, Explicit methods in number theory [slides] |