Activities / Seminars in IMPAN

Academic year 2024 / 2025

24 January 2025 

- Hellen Santana (Universidade de São Paulo) 

- Thais Dalbelo (Universidade Federal de São Carlos)

13 - 14 December 2024 - mini-workshop

(on-site meeting, University of Gdańsk)

 - Szymon Brzostowski ( Łódź) - The Łojasiewicz exponent and polar curves

 - Paweł Goldstein (Warsaw) - Constructing homeomorphisms and diffeomorphisms with prescribed derivatives

 - Rouzbeh Mohseni (Warsaw) - Sasakian manifolds: Old and New

 - Tadeusz Mostowski (Warsaw) - On Marie-Hélène Schwartz's construction of Chern classes in the Lipschitz framework

 - Rafał Pierzchała (Kraków) - On the C^pω category 

 - Artur Piękosz (Kraków) - The development of tame topology

 - Anna Valette (Kraków) - Semialgebraic Whitney partition of unity

 - Andrzej Weber (Warsaw) - How to arrive from nothing to elliptic genus?

22 November 2024 

- 10:00 - 10:50  Anne Pichon (University of Aix-Marseille) 

  Logarithmic links of complex germs and Lipschitz geometry

- 11:00 - 11:50 Dmitry Kerner (Ben-Gurion University of the Negev) 

   Fast cycles and where to find them

25 October 2024 

- 15:30 - 16:20  Michał Farnik (Uniwersytet Jagielloński) 

  Generic symmetry defect set of plane algebraic curves 

- 16:30 - 17:20  Grzegorz Oleksik (Uniwersytet Poznański)  

  On the generic dimension of analytic sets

 

Academic year 2023 / 2024

17 May 2024

- 10:00 - 10:50 Lorenzo Fantini  (École Polytechnique, Paris)  

   Lipschitz geometry of complex surfaces 

10 May 2024

- 10:00 10:50 : Carles Bivià-Ausina (Universitat Politècnica de València) 

  Global multiplicity, special closure and non-degeneracy of polynomial maps

- 11:00 11:50 : Boulos El Hilany (Technische Universität Braunschweig) 

  The polyhedral type of a complex polynomial map on the plane

12 April 2024

- 10:00 10:50 : Dmitry Kerner (Ben-Gurion University of the Negev)

  Which germs are inner-metrically conical? (And how to detect fast vanishing cycles?)

- 11:00 11:50 : Patrick Popescu-Pampu (Université de Lille) 

  Combinatorics of real analytic morsifications

22 March 2024

- 14:00 - 14:45 : Bárbara Karolline de Lima Pereira (Universidade de São Paulo)

   The Relative Bruce-Roberts Numbers of a Function on an Isolated Complete Intersection Singularity

- 14:55 - 15:40 : Otoniel Nogueira da Silva (Universidade Federal da Paraíba) 

   On Zariski multiplicity conjecture for quasihomogeneous surfaces with non-isolated singularities

- 15:50 - 16:35 : Maciej Denkowski (Uniwersytet Jagielloński) 

   On Yomdin's version of a Lipschitz Implicit Function Theorem

1 March 2024

- 10:00 - 10:50 Zbigniew Jelonek (IMPAN)

   Bi-Lipschitz equivalent cones with different degrees

- 11:00-11:50 Adam Różycki (Uniwersytet Łódzki)

   Bi-Lipschitz invariance of the Lê numbers of quasi-ordinary singularities

19 January 2024

- 10:00 - 10:50 : Dmitry Kerner (Ben-Gurion University)

   Artin approximation. The ordinary, the inverse, the left-right, and on quivers

- 11:00-11:50 Jean-Baptiste Campesato (Universite d'Angers)

   Motivic, logarithmic, and topological Milnor fibrations

8 December 2023

- 10:00 - 10:50 : Nicolas Dutertre (Universite d'Angers) 

  On the topology of non-isolated real singularities

- 11:00 - 11:50 : Grzegorz Oleksik (Uniwersytet Łódzki) 

  On Zariski multiplicity conjecture in µ-constant families of non-degenerate singularities

1-2 December 2023

 On-site GKLW mini-workshop, Uniwersytet Jagielloński, Kraków

24 November 2023

- 10:00 - 10:50 : Ursula Ludwig (Univ. Münster)

  Cheeger-Müller theorem for singular spaces

- 11:00 - 11:50 : M'hammed Oudrane (Univ. of Nice)

  Sobolev sheaves on the definable site

13 October 2023

- 10:00 - 10:50 : Jan Stevens (Chalmers Univ. of Technology and Univ. of Gothenburg) 

   Conjectures on stably Newton degenerate singularities

- 11:00 - 11:50 : Victor Goryunov (Univ. of Liverpool)

   Second Arnold-Maslov classes and loops in the spaces of Legendrian and Lagrangian maps of surfaces

 

Academic year 2022 / 2023

2 June 2023

- 10:00 - 11:00 : Evelia Garcia Barroso (Universidad de la Laguna) 

   On the Tjurina and Milnor numbers of a foliation

21 April 2023 

- 14:30 - 15:30 : Maria Michalska (Universidade Federal do Ceara, Fortaleza)

  Classification of Lipschitz normally embedded complex algebraic curves

- 15:45 - 16:45 : Aftab Patel (University of Western Ontario)

  Algebraic approximability of analytic germs

24 March 2023 

- 10:00 - 11:00 : Enrique Artal Bartolo (Universidad de Zaragoza)

   Topology of surface singularities: superisolated, Lê-Yomdin and weighted Lê-Yomdin

- 11:15 - 12:15 : Aleksandra Zakrzewska (Uniwersytet Łódzki)

   Extension of the Gusein-Zade theorem on the jumps equal to 1 of the Milnor number in deformations of plane curve singularities

24 February 2023 - special session with Brazil

- 14:00 - 14:45 : Hellen Monção de Carvalho Santana (University of São Paulo)

   A study on the local topology of a deformation of a function-germ with a one-dimensional critical set

- 15:00 - 15:45 : Taciana  Oliveira Souza (Federal University of Uberlândia)

   On the topology of the Milnor fibration

- 16:00 - 16:45 : Eder Leandro Sanchez Quiceno (University of São Paulo)

   Links of mixed polynomials with a nice Newton inner non-degenerate boundary

20 January 2023

- 10:00 - 11:00 : Armin Rainer (Universität Wien)

  Tame properties of differentiable functions

- 16:00 - 17:00 : Jawad Snoussi (Universidad Nacional Autónoma de México, Cuernavaca)

  On tangency in equisingular families of curves and surfaces

12-16 December 2022 (hybrid, online & IMPAN)

Gdańsk-Kraków-Łódź-Warszawa workshop in Singularity Theory - a special session dedicated to the memory of S. Łojasiewicz

18 November 2022

- 8:00 - 8:45 : Dmitry Kerner (Ben Gurion University of the Negev, Be’er Sheva)

  Generalizations of Newton non-degeneracy for hypersurface singularities

- 9:00 - 9:45 : Christophe Eyral (IMPAN)

   Zeta-function and µ*-Zariski pairs of surfaces

- 10:00 - 10:45 : Goulwen Fichou (Université de Rennes)

   Saturation, seminormalization and homeomorphisms of algebraic varieties

 

Academic year 2021 / 2022

27 May 2022

- 09:00 - 10:00 : Dmitry Kerner (Ben Gurion University of the Negev, Be’er Sheva)

  Germs of maps, group actions and large modules inside group orbits

- 10:15 - 11:15 : Helmut Hamm (Universität Münster)

  An approach to Zariski-van Kampen theorems

29 April 2022 - special session with Vietnam

- 09:00 - 09:45 : Nguyen Tat Thang (Vietnam Academy of Science and Technology, Hanoi)

  Bifurcation set of non-degenerate rational functions

- 10:00 - 10:45 : Nguyen Xuan Viet Nhan (Vietnam Institute for Advanced Study in Mathematics, Hanoi)

  Nice cell decomposition and its application to calculating moderately discontinuous homology

- 11:00 - 11:45 : Pho Duc Tai (Hanoi University of Science, Vietnam National University, Hanoi)

  Elliptic curves with singularities, from geometry, number theory to post-quantum cryptography

25 March 2022

- 10:00 - 11:00 : Lev Birbrair (Federal University of Ceará, Fortaleza)

  Lipschitz geometry of surface germs in R^4: metric knots

- 11:15 - 12:15 : Adam Różycki (Uniwersytet Łódzki)

   Effective Bertini theorem and formulas for multiplicity and the local Łojasiewicz exponent

25 Feb. 2022

- 10:00 - 11:00 : Patricio Almirón (Universidad Complutense de Madrid)

  The minimal Tjurina number and the 4/3 problem for plane curve singularities

- 11:15 - 12:15 : Maciej Denkowski (Uniwersytet Jagielloński)

  Testing Lipschitz non-normally embedded complex spaces

21 Jan. 2022

  10:00 - 11:00 : Juan José Nuño-Ballesteros (Univ. València, Spain)
   The cone structure theorem

17 Dec. 2021 - special session with Brazil

- 14:15 - 15:00 :  Thaís Maria Dalbelo (Univ. Federal de Sao Carlos) 

  Newton Polyhedra and Whitney Equisingularity for Determinantal Singularities

- 15:15 - 16:00 :  José Edson Sampaio (Univ. Federal do Ceara, Fortaleza)

  Differential invariance of the  multiplicity of real and complex analytic sets 

- 16:15 - 17:00 :  Otoniel Nogueira da Silva (Univ. Federal de Sao Carlos) 

  Equisingularity in families of curves and surfaces

26 Nov. 2021

- 10:00 - 11:00 : Jean-Paul Brasselet (I2M CNRS and Aix-Marseille Univ.)

  Generic sections of essentially isolated determinantal singularities

- 11:15 - 12:15 : Meral Tosun (Galatasaray Univ., Istanbul) 

  Lojasiewicz exponent of rational singularities and ideals in their local ring

29 Oct. 2021 

- 10:00 - 11:00 : Mark Spivakovsky (CNRS, Univ. Toulouse)

  μ-constant families of Newton non-degenerate singularities admit simultaneous embedded desingularization 

- 11:15 - 12:15 : Zbigniew Jelonek (IMPAN, Warsaw) 

  On the Fukui-Kurdyka-Paunescu Conjecture

 

Academic year 2020 / 2021

28 May 2021 - special session with Japan

- 09:00 - 10:00 : Mutsuo Oka (Tokyo University of Science)

  Almost non-degenerate functions and a Zariski pair of links

- 10:15 - 11:15 : Toshizumi Fukui (Saitama University)

  Properness of polynomial maps with Newton polyhedrons

30 Apr. 2021

- 10:00 - 11:00 : Wojciech Kucharz (Uniwersytet Jagielloński, Kraków)

  Rational approximation of holomorphic maps

- 11:15 - 12:15 : Marcin Bilski (Uniwersytet Jagielloński, Kraków)

  Effective approximation of the solutions of algebraic equations

26 Mar. 2021

- 10:00 - 11:00 : Meral Tosun (Galatasaray Üniversitesi, Istanbul)

  Simple elliptic singularities and Generalized Slodowy Slices

- 11:15 - 12:15 : Tadeusz Krasiński (Uniwersytet Łódzki)

  The Łojasiewicz exponent in non-degenerate deformations of surface singularities

26 Feb. 2021 - special session with Brazil

- 14:00 - 14:45 : Maria Aparecida Soares Ruas (Universidade de Sao Paulo, Sao Carlos)

  Mixed Bruce-Roberts number

- 15:00 - 15:45 : Vincent Grandjean (Universidade Federal do Ceara, Fortaleza)

  A variation around Malgrange-Rabier condition

- 16:00 - 16:45 : Alexandre Fernandes (Universidade Federal do Ceara, Fortaleza)

  Multiplicity of singular points as a bi-Lipschitz invariant

22 Jan. 2021

- 10:00 - 11:00 : Adam Parusiński (Université de Nice)

  Equisingular families of surface singularities

- 11:15 - 12:15 : Carles Bivia-Ausina (Universitat Politècnica de València)

  Invariants for bi-Lipschitz equivalence of ideals and related topics

11 Dec. 2020

- 10:00 - 11:00 : Wolfgang Ebeling (Leibniz Universität Hannover)

  A McKay correspondence for the Poincaré series of some finite subgroups of SL3(C)

- 11:15 - 12:15 : Jean-Philippe Monnier (Université d'Angers)

  Some normalizations of real algebraic varieties

27 Nov. 2020

- 11:00 - 12:00 : Beata Gryszka (Uniwersytet Pedagogiczny w Krakowie)

  Approximate roots of quasi-ordinary polynomials

- 12:15 - 13:15 : Pedro González Pérez (Unversidad Complutense de Madrid)

  The combinatorics of plane curve singularities. How Newton polygons blossom into lotuses

30 Oct. 2020

- 10:00 - 11:00 : David Trotman (Université d'Aix-Marseille)

  The smooth Whitney fibering conjecture and density of strongly topologically stable maps

- 11:15 - 12:15 : Grzegorz Oleksik (Uniwersytet Łódzki)

  On jumps of the Lê numbers in the family of line singularities