Invited speaker at the following conferences/workshops:
- Petersburg Motives (on the occasion of Ivan Panin's 60th birthday) (2-6.09.2019), St.Petersburg, Russia
- Meeting of CMS Special Session on Equivariant Methods in Differential and Algebraic Geometry (8-10.06.2019), Regina, Canada
- Combinatorial Algebra meets Algebraic Combinatorics (25-27.01.2019), University of Ottawa and Carleton University, Canada
- ABC Algebra Workshop (10-11.11.2018), University of Washington, Seattle, USA
- Affine Algebraic Groups, Motives and Cohomological Invariants (16-21.09.2018), BIRS Banff, Canada
- Ottawa-Lyon-São Paulo Workshop on Representation Theory (03-07.07.2018), Carleton University and the University of Ottawa, Canada
- Motives: arithmetic, algebraic geometry and topology under the white-blue sky (03-07.07.2017), Ludwig-Maximilians-Universitat Munich, Germany
- Beyond Toric Geometry (07-12.05.2017), BIRS Casa Matematica Oaxaca, Mexico
- Algebraic Groups (24-28.04.2017), Oberwolfach, Germany
- Algebraic Cobordism and Projective Homogeneous Varieties (31.01.2016-05.02.2016), Oberwolfach, Germany
- Meeting of CMS Special Session on Cohomological Methods in Quadratic Forms and Algebraic Groups (6-7.12.2015), Montreal, Canada
- (A)round forms, cycles and motives (08-12.09.2014), University of Mainz, Germany
- Structure of Algebraic Groups (23-27.06.2014), Universite Lyon 1, France
- AMS Southeastern Spring Sectional Meeting Galois Cohomology and the Brauer Group (23.03.2014), University of Tennessee, USA
- Algebraic Groups (08-12.04.2013), Oberwolfach, Germany
- Meeting of CMS Special Session on Geometry of Algebraic Varieties (07-10.12.2012), Montreal, Canada
- Joint Mathematics Meetings AMS Special Session on Linear Algebraic Groups: Their Arithmetic, Geometry, and Representations (04-07.01.2012), Boston, USA
- Ramification in Algebra and Geometry (16-20.05.2011), Emory University, USA
- K-Theory and Motives (22-25.03.2011), University of California at Los-Angeles, USA
- Motives and Homotopy Theory of Schemes (16-22.05.2010), Oberwolfach, Germany
- Mini Course-2009 "Torsors and Geometry of Quadrics" (22-26.06.2009), Lens, France
- Quadratic Forms and Linear Algebraic Groups (10-15.05.2009), Oberwolfach, Germany
- Quadratic forms, linear algebraic groups and cohomology (30.12.2008-04.01.2009), University of Hyderabad, India (2 lectures)
- Quadratic forms, Algebraic groups, Algebraic cobordism and Related Topics (26-30.08.2008), University of Nottingham, UK
- Summer school ”Motives of projective homogeneous varieties” (17.09-21.09.2007), Mainz, Germany (4 lectures)
- Workshop "Algebraic cycles, motives and A1-homotopy theory over general bases" (13.02-16.02.2007), Universitat Regensburg, Germany
- Algebraic groups, quadratic forms and related topics (02.09-07.09.2006), Banff, Canada
- Quadratic forms and linear algebraic groups (25.06-01.07.2006), Oberwolfach, Germany
- Mini-Course: "Quadratic Forms" (19.06-23.06.2006), Lens, France
- Workshop "Quadratic Forms, Linear Algebraic Groups, and Related Topics" (09.09 - 16.09.2005), Nottingham, UK
- Workshop on "Algebraic K-Theory, Linear Algebraic Groups and Related Structures" (09.02-11.02.2005), Bielefeld, Germany.
- Workshop on Algebraic K-Theory (02.10 - 05.10.2004), Centre de Recherches Mathematiques, Universite de Montreal, Canada
- Mini-cours, Lens, Juin 2004 "Formes Quadratiques" (21.06 - 25.06.2004), Universite d'Artois, France
- Workshop on Linear Algebraic Groups, Quadratic Forms and Related Topics (01.02 - 05.02.2004), Eilat, Israel
- Short communication at Workshop on Algebraic Groups, Quadratic forms and related topics (30.06 - 04.07.2003), Universite Franch-Comte Besancon, France.
- Algebraic K-Theory (04.08-10.08.2002), Mathematisches Forschungsinstitut Oberwolfach, Germany
- Workshop on Galois Cohomology and Linear Algebraic Groups (24 - 28.06.2002), Institute Bernoulli, EPFL, Lausanne, Switzerland
- Quadratic Forms and Algebraic Groups (12 - 18.05.2002), Mathematisches Forschungsinstitut Oberwolfach, Germany
- Workshop on Witt Groups of Algebraic Varieties (05 - 09.03.2001), Universitaet Muenster, Germany
- Short communication at the Workshop on "Quadratic Forms and their Applications" (05 - 09.07.1999), University College Dublin, Ireland
- Short communication at Summer School on "K-theory and Algebraic Groups" (28.06 - 03.07.1998), Levico-Terme (near Trento), Italy
Colloquium/seminar talks:
- Oberseminar: Motivische algebraische Topologie (04.07.2019),
University of Munich, Germany
- Oberseminar (25.06.2019),
University of Koln, Germany
- Algebra and Representation Theory seminar (20.06.2019),
University of Rome Tor Vergata, Italy
- Algebra Seminar (05.04.2019), University of Ottawa, Canada
- Algebra Seminar (14.03.2019), University of Lyon 1, France
- Seminar (01.08.2018), Chebyshev Laboratory of the St.Petersburg University, Russia
- Oberseminar Algebra und Zahlentheorie (17.07.2018), Mathematical Institute, University of Koln, Germany
- Colloquia (16.03.2018), Dipartimento di Matematica, Universita degli Studi di Roma Tor Vergata, Italy
- Oberseminar Algebra und Zahlentheorie (12.12.2017), Mathematical Institute, University of Koln, Germany
- Algebraic geometry seminar (14.11.2017), Courant Institute, NYU, USA
- Algebra seminar (23.10.2017), SUNY at Buffalo, USA
- Oberseminar "Motivische Algebraische Topologie" (20.07.2017), University of Munich, Germany
- Colloquium (07.10.2016), State University of New York at Albany, USA
- Seminar (30.07.2016), Chebyshev Laboratory of the St.Petersburg University, Russia
- Algebra seminar (12.07.2016), School of Mathematics and Statistics, University of Sheffield, UK
- Seminar (30.05.2016), Department of Mathematics, HSE Moscow, Russia
- Special seminar (23.05.2016, 24.05.2016), Institut Henri Poincare, Paris, France
- Séminaires de l'équipe de Topologie Algébrique (18.05.2016), Universite Paris 13, France
- Oberseminar "Motivische Algebraische Topologie" (12.05.2016), University of Munich, Germany
- Algebra Seminar (17.03.2016), University of Lyon 1, France
- Séminaire "Variétés rationnelles" (11.03.2016), École Normale Supérieure, Paris, France
- Topology Seminar (29.02.2016), University of Manchester, UK
- Pure Mathematics Seminar (25.02.2016), University of Lancaster, UK
- Geometric Representation Theory Seminar (30.11.2015), Fields Institute, Toronto, Canada
- Algebra Seminar (18.11.2015), University of Alberta, Canada
- Oberseminar Algebra, Geometrie und Zahlentheorie (18.12.2014), Universitat Duisburg-Essen, Germany
- Algebra seminar (14.11.2014), KAIST, Daejeon, Korea
- Colloquium (13.11.2014), KAIST, Daejeon, Korea
- Algebra and Lie groups seminar (14.10.2014), Yale University, USA
- Colloquium (10.10.2014), State University of New York at Albany, USA
- Geometry seminar (06.05.2014), Courant Institute of Mathematical Sciences, USA
- Algebra seminar (24.03.2014), University of Virginia, USA
- Geometry and Topology seminar (27.01.2014), Western University, Canada
- Colloquium (14.10.2013), University of Maryland, USA
- Topology and related seminars (07.08.2013), University of British Columbia, Canada
- Algebraic geometry seminar (06.08.2013), University of British Columbia, Canada
- Thematic Program visitors seminar (15.03.2013), Fields Institute, Toronto, Canada
- Geometric Representation Theory Seminar (14.03.2013), Fields Institute, Toronto, Canada
- Algebra seminar (27.04.2012), University of Virginia, USA
- Colloquium (26.04.2012), University of Virginia, USA
- Algebra Seminar (28.11.2011), University of Alberta, Canada
- Algebra and Number Theory Seminar (07.11.2011), Emory University, USA
- Algebraic Groups Seminar (25.10.2011), University of British Columbia, Canada
- Algebraic Geometry seminar (24.10.2011), University of British Columbia, Canada
- Geometry and Topology seminar (23.09.2011), Universite du Quebec a Montreal, Canada
- Algebra Seminar (03.03.2011), University of Alberta, Canada
- Algebraic Geometry seminar (22.11.2010), Queen's University, Canada
- Séminaires de l'équipe de Topologie Algébrique (24.06.2010), Universite Paris 13, France
- Algebra Colloquium (11.03.2010), University of California at Los Angeles, USA
- Geometry and topology seminar (25.01.2010), University of Western Ontario, Canada
- Joint seminar Regensburg-Munchen (17.07.2009), University of Regensburg, Germany
- Algebraic Geometry and Arithmetic seminar (19.02.2009), University of Liverpool, UK
- Seminaire "Varietes rationnelles" (13.02.2009), ENS Paris, France
- Algebra Seminar (15.01.2009), University of Ottawa, Canada
- Seminaire Autour des Cycles Algebriques (05.11.2008), University Paris 6, France
- Geometry Seminar (03.10.2008), University of Cambridge, UK
- Seminario di Algebra e Geometria (29.05.2008), University of Genua, Italy
- Pure Math Colloquium (07.05.2008), University of Sheffield, UK
- Number theory seminar (08.02.2008), University of Nottingham, UK
- Seminar "Algebraische Gruppen" (02.07.2007), Universitat Bielefeld Germany.
- Seminar "Algebraische Gruppen" (23.01.2007), Universitat Bielefeld Germany.
- Seminaire de theorie des nombres de Chevaleret (18.12.2006), University of Paris 7, France
- Arbeitsgemeinschaft Algebra und Topologie (15.12.2006), University of Basel, Switzerland
- Seminar "Arithmetische Geometrie" (15.11.2006), University of Goettingen, Germany
- Seminar DFG-Forschergruppe (03.11.2006), University of Regensburg, Germany
- Oberseminar "Motivische Algebraische Topologie" (27.04.2006), University of Muenchen, Germany
- Staffcolloqium (06.04.2006), University of Utrecht, Netherlands
- Algebra seminar (28.02.2006), University of Edmonton, Canada
- Number Theory Seminar (24.01.2006), Max-Planck-Institut fur Mathematik, Bonn, Germany.
- Oberseminar "Agebra und Homotopie" (19.10.2005), University of Bielefeld, Germany
- Oberseminar "Arithmetische Geometrie" (15.06.2005), University of Goettingen, Germany
- Number Theory Seminar (08.06.2005), Max-Planck-Institut fur Mathematik, Bonn, Germany
- AG Algebraische Gruppen (10.05.2005), University of Bielefeld, Germany
- Séminaire "Variétés rationnelles" (15.01.2005), École Normale Supérieure, Paris, France
- Algebra - Topology Seminar (17.01.2005), ETH, Zürich, Switzerland
- Forschungsseminar "Algebraische Geometrie" (23.11.2004), Humboldt Universität zu Berlin, Germany
- Arithmetische Geometrie seminar (05.11.2004), Universität Regensburg, Germany
- Oberseminar Algebraische Gruppen (27.10.2004), Mathematisches Institut Georg-August-Universität Göttingen, Germany
- Oberseminar Algebraische Geometrie (05.05.2004), Mathematisches Institut Georg-August-Universität Göttingen, Germany
- Department Seminar (12.01.2004), Mathematisches Institut, Universität Heidelberg, Germany
- MathDepartment Seminar (07.07.2003), Essen University, Germany
- SFB478 seminar (15.05.2003), University of Münster, Germany
- Seminaire d'Algebre et de Theorie des Nombres (14.03.2002), Ecole Polytechnique Federale de Lausanne, Switzerland
- Groupe de travail de Geometrie Algebrique (22.02.2002), Institut des Hautes Etudes Scientifiques, Bures-sur-Yvette, France
- Séminaire "Variétés rationnelles" (24.11.2001), École Normale Supérieure, Paris, France
- Seminar des Graduiertenkollegs (07.06.2001), Universitaet Muenster, Germany