Friday Fish seminars

History: Between December 2016 and February 2020 I have been the organiser of the Friday Fish seminars (the weekly seminars of the differential geometry research group of Universiteit Utrecht). The talks were announced weekly via a mailing list and put on the online calendar of the maths department. In this page, for the sake of keeping records, I collected below the schedule of the talks given in that period.

If you want to know what happened in the Friday Fish before December 2016, you can scroll the calendar on the older website http://www.projects.science.uu.nl/poisson/activities.html (it goes back until September 2013 - but the first seminars actually dates back to 2004).

During the pandemic the seminar has been digitalised and globalised, but in the academic year 2021-2022 it returned to the older (physical) format. The general information written below may no longer be applicable: please see the current webpage.

General information: Usually we have one or two speakers per week, each of them talking for roughly an hour and a half (45 + 45 minutes, with a break in the middle and time for questions at the end) in the time slots 11-13 and 15-17 on Friday, in room 610 of the Mathematics Department; of course, basing on the preferences and the availabilities of the speakers and other circumstances, the time and place can be changed (and occasionally even the day).

The atmosphere is quite informal, the audience is in general small (usually about 10 people, never more than 15-20), so it's a perfect occasion for talking in a "safe environment" about the latest paper you published, the problem you're currently working on, the paper you're reading, the topic of your bachelor or master thesis (students are welcome too), etc.

All the speakers were affiliated with Universiteit Utrecht at the time of their talk, unless written otherwise.

• Persistence modules in geometry (Vukašin Stojisavljević, Tel Aviv University)

Room 610, 4 February 2020, 17.15 - 19.15 (TUESDAY)

• Submersions by Lie algebroids (Pedro Frejlich, Universidade Federal Rio Grande do Sul, Porto Alegre)

Room 610, 31 January 2020, 14.00-16.00

• Introduction to spinors (Santiago Quintero)

Room 802, 9 January 2020, 14.00.16.00 (THURSDAY)

(Christmas break)

• Romanian Fish: no seminar due to the Contact and Poisson geometry workshop in Timișoara (https://sites.google.com/view/wcpg/home)

1 November 2019

• Homogeneous G-Structures (Luca Vitagliano, Università degli Studi di Salerno)

Room 610, 18 October 2019, 14.00-16.00

(summer break)

• A normal form for Hamiltonian groupoid actions II (Maarten Mol)

Room 610, 19 July 2019, 15.30-17.30

• Infinitesimal picture, Van Est theorem and characteristic map for étalifications (Luca Accornero)

Room 610, 19 July 2019, 13.00-15.00

• Poisson structures on vector bundles III: Normal form(s) of elliptic symplectic (Aldo Witte)

Room 610, 19 July 2019, 10.00-12.00

• A normal form for Hamiltonian groupoid actions (Maarten Mol)

Room 610, 12 July 2019, 14.00-16.00

• Poisson structures on vector bundles II: Naive approximation of Poisson structures (Aldo Witte)

Room 610, 12 July 2019, 11.00-13.00

• Differentiable cohomology of Lie pseudogroup - second try (Luca Accornero)

Room 610, 5 July 2019, 16.00-18.00

• Differentiable cohomology of \Gamma^q (Luca Accornero)

Room 610, 21 June 2019, 16.00-18.00

• The linearization and canonical stratification of proper Lie groupoids (Maarten Mol)

Room 610, 21 June 2019, 13.30-15.30

• Poisson structures on vector bundles I: ''Fibrewise linear Poisson structures and Poisson connections" (Aldo Witte)

Room 610, 21 June 2019, 10.30-12.30

• Fish along the Lower Rhine: no seminar due to the "Higher Geometric Structures along the Lower Rhine" workshop in Utrecht (https://www.uu.nl/en/events/higher-geometric-structures-along-the-lower-rhine-xiii)

14 June 2019

• A characterization of 3D steady Euler flows (Francisco Torres de Lizaur, Max Planck Institute for Mathematics, Bonn)

Room 610, 7 June 2019, 11.00-13.00

• No Fish in Heaven: no seminar due to public holiday (Hemelvaartsdag)

31 May 2019

• Rigidity for loops of Legendrian knots (Francisco Javier Martínez-Aguinaga, Instituto de Ciencias Matemáticas, Universidad Complutense de Madrid)

Room 610, 30 May 2019, 13.00-15.00 (THURSDAY)

• Kan Fish: no seminar due to the Kan lectures by Fabien Morel (https://www.uu.nl/en/events/kan-lectures-2019-fabien-morel-munchen)

24 May 2019

• Connecting Fish: no seminar due to the Symposium "Connecting Mathematical Methods across Utrecht University" (https://www.uu.nl/en/events/annual-symposium-connecting-mathematical-methods-across-utrecht-university-edition-2019).

3 May 2019

(Easter break)

• The Atiyah-Bott Localization Formula (Sergej Monavari)

Room 610, 10 April 2019, 15.00-17.00 (WEDNESDAY)

• Borel Model for Equivariant Cohomology (Sergej Monavari)

Room 610, 3 April 2019, 15.00-17.00 (WEDNESDAY)

• A de Rham theorem for BG (Maarten Mol)

Room 610, 29 March 2019, 15.00-17.00

• Principal g-DGAs and the Weil algebra (Maarten Mol)

Room 610, 21 March 2019, 13.00-15.00 (THURSDAY!)

• Symplectic Fish: no seminar due to the Symplectic Geometry workshop in Utrecht (https://www.staff.science.uu.nl/~zilte001/symplectic_2019_03_15/index.php)

15 March 2019

• CAST(ing a) Fish(ing rod): no seminar due to the workshop on Symplectic geometry, contact geometry and interaction in Berlin (https://www2.mathematik.hu-berlin.de/~wendl/CAST2019/).

8 March 2019

• Universal bundles II - simplicial approach and existence (Luca Accornero)

Room 610, 1 March 2019, 15.00-17.00

• Universal bundles I: classification theorem and examples (Luca Accornero)

Room 610, 22 February 2019, 15.00-17.00

• An introduction to equivariant cohomology and localization formulas (Maarten Mol)

Room 610, 15 February 2019, 14.00-16.00

• Conformal symplectic foliations III (Lauran Toussaint)

Room 409, 8 February 2019, 15.00-17.00 (DIFFERENT ROOM)

• Fish along the Lower Rhine: no seminar due to the "Higher Geometric Structures along the Lower Rhine" workshop in Nijmegen (https://www.math.ru.nl/~sagave/higher-structures-XII/)

1 February 2019

• Deformations of symplectic groupoids (João Nuno Mestre, Max Planck Institute for Mathematics, Bonn)

Duistermaat Room (5th floor), 30 January 2019, 15.00-17.00 (WEDNESDAY, DIFFERENT ROOM THAN USUAL)

• Positive complexity one spaces (Daniele Sepe, Universidade Federal Fluminense, Rio de Janeiro)

Room 610, 30 January 2019, 11.00-13.00 (WEDNESDAY)

• The rational cohomology of affine Grassmanians (Jack Davies)

Room 610, 25 January 2019, 15.00-17.00

• Contact structures and conformal symplectic foliations II (Lauran Toussaint)

Room 610, 25 January 2019, 11.00-13.00

• Contact structures and conformal symplectic foliations (Lauran Toussaint)

Room 610, 18 January 2019, 14.00-16.00

• The Madsen-Weiss theorem: delooping II (Álvaro del Pino Gómez)

Room 610, 11 January 2019, 14.30-17 (STARTS 30 MINUTES EARLIER)

(Christmas break)

• Fish along the Waal: no seminar due to the "Poisson aan de Waal" workshop in Nijmegen (https://www.ru.nl/math/vm/events/@1180277/poisson-waal-12-14-december-2018/)

14 December 2018

• Madsen-Weiss II: Deloopings (Aldo Witte)

Duistermaat room (5th floor), 11 December 2018, 11.00-13.00 (DIFFERENT ROOM, TIME AND DAY)

• GQT Fish: no seminar due to GQT colloquium in Groesbeek (https://gqt.nl/colloquium/conference/)

30 November 2018

• Madsen Weiss Theorem, part I (Luca Accornero)

Room 610, 23 November 2018, 15.00-17.00

• The group completion theorem (Lennart Meier)

Room 610, 9 November 2018, 15.00-17.00

• The Earle-Eells theorem on diffeomorphism groups of surfaces (Álvaro del Pino Gómez)

Room 610, 2 November 2018, 15.00-17.00

• Transversely Integrable Lie Algebroids and Asymmetric Orbispaces (Joel Villatoro, KU Leuven)

Room 610, 26 October 2018, 15.30-16.30

• Almost regular Poisson structures and their holonomy groupoids (Marco Zambon, KU Leuven)

Room 610, 26 October 2018, 14.00-15.00

• Introduction to the Madsen-Weiss theorem (Thomas Rot, Vrije Universiteit Amsterdam)

Room 610, 19 October 2018, 15.00-17.00

• Towards the understanding of Asymptotically conical scalar flat Kähler metrics (Simone Siclari, Aarhus Universitet)

Room 610, 19 October 2018, 11.00-13.00

• Finding the local and global solutions to Cartan's Realization Problem III (Rui Loja Fernandes, University of Illinois at Urbana Champaign)

Room 610, 9 October 2018, 13.30-15.30 (TUESDAY)

• Finding the local and global solutions to Cartan's Realization Problem II (Rui Loja Fernandes, University of Illinois at Urbana Champaign)

Room 610, 5 October 2018, 11.00-13.00

• Finding the local and global solutions to Cartan's Realization Problem (Rui Loja Fernandes, University of Illinois at Urbana Champaign)

Room 610, 2 October 2018, 14.00-16.00 (TUESDAY)

• Symplectic Fish: no seminar due to the Symplectic Geometry workshop in Amsterdam (https://www.staff.science.uu.nl/~zilte001/symplectic_2018_09_20__21/index.php)

21 September 2018

• Italian Fish: no seminar due to the workshop on Poisson geometry and Higher structures in Roma (http://www1.mat.uniroma1.it/ricerca/convegni/2018/hippo2018/index.html)

14 September 2018

(summer break)

• Canadian Fish: no seminar due to the Poisson geometry school (http://www.fields.utoronto.ca/activities/18-19/poisson-summer-school) and conference (http://www.fields.utoronto.ca/activities/18-19/poisson-2018) in Toronto

14-21 July 2018

• Generalized monodromy in integrable Hamiltonian systems (Nikolay Martynchuk, Rijksuniversiteit Groningen)

Room 610, 29 June 2018, 14.00-16.00

• Kan Fish: no seminar due to the Kan lectures by Eric Friedlander (https://www.uu.nl/en/events/kan-lectures-2018-eric-friedlander-university-of-southern-california)

15 June 2018

• GQT Fish: no seminar due to the GQT colloquium in Groesbeek (https://gqt.nl/colloquium/conference/)

8 June 2018

• Shifted symplectic structures (Brice Le Grignou)

Room 610, 1 June 2018, 14.00-16.00

• An Application of the theory of EDS to G-Structures (Ori Yudilevich, Katholieke Universiteit Leuven)

Room 610, 28 May 2018, 11-13 (MONDAY)

• About a Kontsevich conjecture on vertex models (Damien Lejay, Pohang University of Science and Technology)

Room 610, 25 May 2018, 14.00-16.00

• Geometric decompositions of almost contact manifolds (Francisco Presas, Instituto de Ciencias Matemáticas, Madrid)

Room 610, 18 May 2018, 13.00-15.00

• Cartan's Realization Problem for G-Structures (Ivan Struchiner, Universidade de São Paulo)

Room 610, 18 May 2018, 10.00-12.00

• No Fish in Heaven: no seminar due to public holiday (Hemelvaartsdag)

11 May 2018

• Fishy data analysis: no seminar due to the UGC masterclass on topological data analysis by Vidit Nanda (https://www.uu.nl/en/events/masterclass-topological-data-analysis)

4 May 2018

• Overview of prolongation theory (Luca Accornero)

Room 610, 30 April 2018, 11.00-13.00 (MONDAY)

• No Fish for the King: no seminar due to public holiday (Koningsdag)*

27 April 2018

* Unless the sudden death or abdication of the king, or a Republican coup d'état will revoke such celebration; in that case the Monday talk will be anticipated on Friday (same time, same room).

• Derived stacks (Joost Nuiten)

Room 610, 20 April 2018, 14.00-16.00

• EDSs and PDEs (Francesco Cattafi)

Room 610, 20 April 2018, 11.00-13.00

• Affine Derived Algebraic Geometry (Brice Le Grignou)

Room 610, 13 April 2018, 14.00-16.00

• Cartan-Kähler theorem and Cartan test (Luca Accornero)

Room 610, 13 April 2018, 11.00-13.00

(Easter break)

• K3 surfaces and PMSCTs (Luka Zwaan)

Room 610, 23 March 2018, 14.00-16.00

• Proof and consequences of the Cartan-Kähler theorem (Francesco Cattafi)

Room 610, 23 March 2018, 11.00-13.00

• Symplectic Fish: no seminar due to the Symplectic Geometry workshop in Utrecht (https://www.staff.science.uu.nl/~zilte001/symplectic_2018_03_16/index.php)

16 March 2018

• Integral elements of EDS: fundamental properties and Cartan test (Luca Accornero)

Room 610, 15 March 2018, 13.00-15.00 (THURSDAY)

• Generalised complex geometry VI (Aldo Witte)

Duistermaat room (5th floor), 12 March 2018, 15.30-17.30 (MONDAY)

• K3 surfaces - basic properties (Luka Zwaan)

Duistermaat room (5th floor), 12 March 2018, 13.00-15.00 (MONDAY)

• Fish along the Lower Rhine: no seminar due to the "Higher Geometric Structures along the Lower Rhine" workshop in Bonn (http://www.mpim-bonn.mpg.de/node/7958)

9 March 2018

• Generalized complex V: Complex log symplectic structures (Aldo Witte)

Room 610, 2 March 2018, 14.00-16.00

• Introduction to EDS and Cartan-Kähler theorem (Francesco Cattafi)

Room 610, 2 March 2018, 11.00-13.00

• Formality of fibrations (Bjarne Kosmeijer)

Room 610, 23 February 2018, 14.00-16.00

• Generalized complex IV: Generalized Darboux (Aldo Witte)

Room 610, 23 February 2018, 11.00-13.00

• Formality & geometric structures (Bjarne Kosmeijer)

Room 610, 16 February 2018, 14.00-16.00

• Generalized complex geometry (Aldo Witte)

Room 610, 16 February 2018, 11.00-13.00

• Generalized complex geometry: Spinors (Aldo Witte)

Room 610, 9 February 2018, 13.00-15.00

• Stable generalized complex structures: Dirac geometry (Aldo Witte)

Room 610, 2 February 2018, 13.00-15.00

• Hairy Fish and Friday Mole: no seminar due to the master thesis presentation of Rik Voorhaar ("Higher Gauge Theory") and Maarten Mol ("A classification of toric actions by symplectic torus bundles")

19 January 2018

(Christmas break)

• Arnol'd conjecture and sheaves (Davide Alboresi)

Room 610, 15 December 2017, 13.00-15.00

• Sheaf quantization of Hamiltonian isotopies (Dušan Joksimović)

Room 610, 8 December 2017, 13.00-15.00

• Flexibility for bracket-generating distributions (Francisco Javier Martínez Aguinaga, Universidad Complutense de Madrid)

Room 610, 1 December 2017, 15.30-17.30

• The Arnol'd conjecture. Part I (Álvaro del Pino Gómez)

Room 610, 1 December 2017, 13.00-15.00

• Functorial operations and the Microsupport of Sheaves (Kay Werndli)

Room 610, 24 November 2017, 13.00-15.00

• Branes with boundary and symplectic methods for stable generalised complex manifolds (Charlotte Kirchhoff-Lukat, University of Cambridge)

Room 610, 24 November 2017, 11.00-12.00

• S-immersions (Álvaro del Pino Gómez)

Room 610, 17 November 2017, 15.30-17.30

• Morse theorem for microsupport (Luca Accornero)

Room 610, 17 November 2017, 13.00-15.00

• Wrinkled submersions II (Lauran Toussaint)

Room 610, 10 November 2017, 15.30-17.30

• Microsupport of sheaves (Davide Alboresi)

Room 610, 10 November 2017, 13.00-15.00

• Wrinkled submersions (Lauran Toussaint)

Springer room (7th floor), 3 November 2017, 15.30-17.30 (DIFFERENT ROOM)

• Derived functors and operations between sheaves (Dušan Joksimović)

Room 610, 3 November 2017, 13.00-15.00 (USUAL ROOM)

• Holonomic Approximation II (Florian Zeiser)

Room 610, 27 October 2017, 15.30-17.30

• The six operations on sheaves (Álvaro del Pino Gómez)

Room 610, 27 October 2017, 13.00-15.00

• Fish along the Lower Rhine: no seminar due to the "Higher Geometric Structures along the Lower Rhine" workshop in Utrecht (http://www.projects.science.uu.nl/Moerdijk/HigherLower%202017%20home%202.htm)

20 October 2017

• Holonomic Approximation (Florian Zeiser)

Room 610, 13 October 2017, 15.30-17.30

• Derived categories and derived functors (Peter James)

Room 610, 13 October 2017, 13.00-15.00

• Hard Lefschetz Theorem for Sasakian manifolds (Antonio de Nicola, Università degli Studi di Salerno)

Room 610, 6 October 2017, 16.00-18.00

• The symplectic-to-contact dictionary (Luca Vitagliano, Università degli Studi di Salerno)

Room 610, 6 October 2017, 14.00-16.00

• Introduction to sheaf theory in symplectic topology (Davide Alboresi)

Room 610, 29 September 2017, 15.30-17.30

• Introduction to h-principle (Álvaro del Pino Gómez)

Room 610, 29 September 2017, 13.00-15.00

• Higher Gauge Theory II: (2-)Gauge Theory (Rik Voorhaar, Université de Genève)

Room 610, 22 September 2017, 11.00-13.00

• Higher Gauge Theory I: (1-)Gauge Theory (Rik Voorhaar, Université de Genève)

Room 610, 15 September 2017, 11.00-13.00

(summer break)

• Deformation quantization of other kinds of spaces (Micheal Bailey)

Room 610, 21 July 2017, 15.00-17.00

• Proof of Delzant's Theorem II (Maarten Mol)

Room 610, 14 July 2017, 15.00-17.00

• Proof of Delzant's Theorem I (Maarten Mol)

Room 610, 14 July 2017, 11.00-13.00

• GQT Fish: no seminar due to the GQT colloquium in Den Dolder (https://www.projects.science.uu.nl/gqt/GQT_colloquium/Conference.html)

7 July 2017

• White Fish: no seminar due to the master thesis presentation of Aldo Witte ("A new view on a symplectic foliation on the five-sphere")

30 June 2017

• The faces of a moment polytope (Maarten Mol)

Room 610, 30 June 2017, 11.00-13.00

• A local normal form for Hamiltonian torus-spaces (Maarten Mol)

Room 610, 23 June 2017, 15.00-17.00

• Deformation quantization I (Micheal Bailey)

Room 610, 16 June 2017, 11.00-13.00

• Kan Fish: no seminar due to the Kan lectures by Ib Madsen (https://www.uu.nl/en/events/kan-lectures-2017-ib-madsen-copenhagen)

2 June 2017

• No Fish in Heaven: no seminar due to public holiday (Hemelvaartsdag)

26 May 2017

• Geometric structures, integrability and Pfaffian groupoids (Francesco Cattafi)

Room 610, 15 May 2017, 11.00-13.00 (MONDAY)

• Fish along the Lower Rhine: no seminar due to the "Higher Geometric Structures along the Lower Rhine" workshop in Nijmegen (http://www.math.ru.nl/~sagave/higher-structures-IX/)

12 May 2017

• Liberation Fish: no seminar due to public holiday (Bevrijdingsdag)

5 May 2017

(Easter break)

• Torus loop groups and their representations (Shan Shah)

Room 610, 31 March 2017, 15.00-17.00

• Convexity theorem for moment maps (Rik Voorhaar, Université de Genève)

Duistermaat room (5th floor HFG), 20 March 2017, 13.00-15.00

• Symplectic Fish: no seminar due to the Symplectic Geometry workshop in Utrecht (https://www.staff.science.uu.nl/~zilte001/symplectic_2017_03_17/index.php)

17 March 2017

• Symplectic foliations from Donaldson Open Books IV.bis (Aldo Witte)

Room 610, 10 March 2017, 11.00-12.00

• Symplectic foliations from Donaldson Open Books IV (Aldo Witte)

Room 610, 3 March 2017, 11.00-13.00

• Symplectic foliations from Donaldson Open Books III (Aldo Witte)

Room 610, 24 February 2017, 11.00-13.00

• Symplectic foliations from Donaldson Open Books II (Aldo Witte)

Room 610, 17 February 2017, 11.00-13.00

• Symplectic foliations from Donaldson Open Books (Aldo Witte)

Room 610, 10 February 2017, 11.00-13.00

• Constructing A-symplectic structures (Ralph Klaasse)

Room 610, 20 January 2017, 13.00-15.00

• 2-vector bundles over differentiable stacks (Matias del Hoyo, Universidade Federal Fluminense, Rio de Janeiro)

Room 610, 20 January 2017, 10.00-12.00

• Blowing up Riemannian Lie groupoids (Kirsten Wang, Universiteit van Amsterdam)

Room 610, 18 January 2017, 13.00-15.00 (WEDNESDAY)

• Proper Lie groupoids are real analytic (David Martínez Torres, Pontifícia Universidade Católica do Rio de Janeiro)

Room 610, 16 January 2017, 14.00-16.00 (MONDAY)

• Multiplicity Free Realizations of Poisson Manifolds (Rui Loja Fernandes, University of Illinois at Urbana-Champaign)

Room 610, 16 January 2017, 11.00-13.00 (MONDAY)

• Splitting theorems for Poisson and Dirac structures (Ralph Klaasse)

Room 610, 13 January 2017, 15.00-17.00

(Christmas break)

• Fish along the Lower Rhine: no seminar due to the "Higher Geometric Structures on the Lower Rhine" workshop in Bonn (http://www.mpim-bonn.mpg.de/node/6832)

16 December 2016

• On exotic differentiable structures on spheres (Jeroen van der Meer)

Room 610, 9 December 2016, 15.00-17.00

• What is a formal moduli problem? (Brice Le Grignou)

Room 610, 9 December 2016, 11.00-13.00

• GQT Fish: no seminar due to the GQT colloquium in Den Dolder (http://www2.projects.science.uu.nl/GQT/GQT_colloquium/Conference.html)

2 December 2016