The acronym GKŁW stands for Gdańsk-Kraków-Łódź-Warszawa. The GKŁW seminar in Singularity Theory is a monthly, online seminar organized by C. Eyral (Institute of Mathematics of the Polish Academy of Sciences, Warszawa), T. Krasiński (University of Łódź), A. Nowel (University of Gdańsk) and A. Valette (Jagiellonian University, Kraków). In addition to the online lectures, twice a year, a mini-workshop on-site is also organized in one of our four host institutions.
Websites
https://gklw.matinf.uj.edu.pl/index.php
Gdańsk-Kraków-Łódź-Warszawa Seminar in Sigularity Theory (impan.pl)
Academic year 2025 / 2026
3-4 October 2025
Mini-workshop in Singularity Theory (on-site, IMPAN, Warsaw)
Academic year 2024 / 2025
30-31 May 2025
Mini-workshop in Singularity Theory (on-site, IMPAN, Warsaw)
16 May 2025
08:00 - 08:50 Leslie Wilson (University of Hawaii)
Bilipschitz geometry of real surface singularities whose tangent cone is a plane
9 May 2025
10:00 - 10:50 Taketo Shirane (Tokushima University)
Combinatorial type and splitting invariants of plane curves
4 April 2025
• 10:00 - 10:50 María Pe Pereira (Universidad Complutense de Madrid)
A theory to study metric degenerations: Moderately Discontinuous Algebraic Topology
• 11:00 - 11:50 Maciej Denkowski (Uniwersytet Jagielloński)
Lipschitz Normally Embedded Hölder Triangles in R4
7 March 2025
• 10:00 - 10:50 Dmitry Kerner (Ben-Gurion University of the Negev)
Deforming the weighted-homogeneous foliation of (kN, 0), and trivializing families of semi-weighted homogeneous ICIS
• 11:00 - 11:50 Aftab Patel (University of Rennes)
An open problem in algebraic approximation of analytic singularities
24 January 2025 - special session with Brazil
• 14:00 - 14:50 Hellen Santana (Universidade de São Paulo)
Brasselet number: a generalization of the local Euler obstruction
• 15:00 - 15:50 Thais Dalbelo (Universidade Federal de São Carlos)
Stratified Morse critical points and locally tame singularities
13 - 14 December 2024
Mini-workshop in Singularity Theory (on-site, University of Gdańsk)
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 - special session with Brazil
- 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 (Be’er Sheva)
Artin approximation. The ordinary, the inverse, the left-right, and on quivers
- 11:00 - 11:50 : Jean-Baptiste Campesato (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 (29 lectures)
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 February 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 January 2022
- 10:00 - 11:00 : Juan José Nuño-Ballesteros (Univ. València, Spain)
The cone structure theorem
17 December 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 November 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 October 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