Seminarium Zakładu Funkcji Rzeczywistych

16/02/20

Seminar of the Division of Real Functions

Forthcoming lectures:

Time and place: usually on Tuesdays at 10:15 in room 122

  • 2020-02-18: Krzysztof Kowitz, Arithmetic progressions in lacunary sets
    Abstract: Talk based on the paper T.C. Brown and A.R. Freedman „Arithmetic progressions in lacunary sets”, Rocky Mountain J. Math.Volume 17, Number 3 (1987), 587-596.
  • 2020-02-25: Wojciech Wołoszyn, Modal model theory
    Abstract I shall introduce the subject of modal model theory, a research effort bringing modal concepts and vocabulary into model theory. For any first-order theory T, we may naturally consider the models of T as a Kripke model under the submodel relation, and thereby naturally expand the language of T to include the modal operators. In the class of all graphs, for example, a statement is possible in a graph, if it is true in some larger graph, having that graph as an induced subgraph, and a statement is necessary when it is true in all such larger graphs. The modal expansion of the language is quite powerful: in graphs it can express k-colorability and even finiteness and countability. The main idea applies to any collection of models with an extension concept. The principal questions are: what are the modal validities exhibited by the class of models or by individual models? For example, a countable graph validates S5 for graph theoretic assertions with parameters, for example, just in case it is the countable random graph; and without parameters, just in case it is universal for all finite graphs. Similar results apply with digraphs, groups, fields and orders. This is joint work with Professor Joel David Hamkins, Oxford University.

History of the Seminar

Pictures

SeminarGroup-2017-1SeminarGroup-2017-2

Past lectures

2020

  • 2020-01-21: Krzysztof Kowitz, van der Waerden spaces and Hindman spaces are not the same
  • 2020-01-14: Piotr Nowakowski (Lodz University of Technology), Microscopic sets among symmetric Cantor sets

2019

  • 2020-01-07: Jacek Tryba, Different kinds of density ideals
  • 2019-12-17: Stanisław Kowalczyk (Pomeranian University in Słupsk), On sets of points of quasicontinuity and porouscontinuity
  • 2019-12-10: Piotr Szuca, ω-diagonalizability of Fσ filters (continuation)
  • 2019-12-03: Franciszek Prus-Wiśniowski (University of Szczecin), The arithmetic sums of central Cantor sets
  • 2019-11-26: Piotr Szuca, ω-diagonalizability of Fσ filters (continuation)
  • 2019-11-19: Piotr Szuca, ω-diagonalizability of Fσ filters
  • 2019-11-05: Adam Kwela, Generalized density ideals versus density-like ideals (continuation)
  • 2019-10-29: Adam Kwela, Generalized density ideals versus density-like ideals
  • 2019-10-22: Adam Ostaszewski (London School of Economics, UK), Multivariate regular variation and Popa homomorphisms
  • 2019-10-15: Eliza Jabłońska (Pedagogical University of Cracow), Generically Haar-”small” sets in abelian Polish groups
  • 2019-10-08: Arturo Martínez-Celis (Institute of Mathematics of the Polish Academy of Sciences), P+-filters of finite sets
  • 2019-09-27: Ziemowit Kostana (University of Warsaw and Institute of Mathematics of the Czech Academy of Sciences), On big subgroups evading small sets
  • 2019-06-04: Rafał Filipów, Ideals generated by families of sequences of natural numbers – topological complexity
  • 2019-05-28: Adam Ostaszewski (London School of Economics, UK), The Steinhaus support: Beyond the confines of Haar and Cameron-Martin
  • 2019-05-21: Jaroslav Šupina (Pavol Jozef Šafárik University in Košice, Slovakia), On ideal cardinal invariants and singular sets
  • 2019-05-14: Michał Banakiewicz (West Pomeranian University of Technology, Szczecin), The set of subsums of the Guthrie-Nymann-Jones series
  • 2019-05-07: Rafał Filipów, Ideals generated by families of sequences of natural numbers – basic properties
  • 2019-04-25: Wojciech Wołoszyn (Oxford University, UK), On the multiverse, potentialism, and implicit actualism
  • 2019-04-16: Piotr Szuca, The structure of equicontinuous maps
  • 2019-04-09: Tomasz Natkaniec, Different notions of Sierpiński-Zygmund functions (continuation)
  • 2019-04-02: Tomasz Natkaniec, Different notions of Sierpiński-Zygmund functions
  • 2019-03-26: Jacek Tryba, A proof of a sumset conjecture of Erdős
  • 2019-03-19: Adam Kwela, Nonmeasurable subgroups of compact groups
  • 2019-03-12: Bartosz Kamedulski, G-spaces, equivariant degree and its product property
  • 2019-03-05: Andrzej Nowik, Ideals of nowhere dense sets in some topologies on positive integers (continuation)
  • 2019-02-26: Andrzej Nowik, Ideals of nowhere dense sets in some topologies on positive integers
  • 2019-02-21: Adam Ostaszewski (London School of Economics, UK), Kendall’s sequential characterization of regular variation: Category versus measure
  • 2019-02-19: Piotr Sworowski (Casimir the Great University in Bydgoszcz), Comparison of some trigonometric integrals (continuation)
  • 2019-01-22: Edward Grzegorek, On σ-algebras closed under Souslin’s operation and Stanisław Saks theorem
  • 2019-01-15: Piotr Sworowski (Casimir the Great University in Bydgoszcz), Comparison of some trigonometric integrals

2018

  • 2018-12-18: Gertruda Ivanova (Pomeranian University in Słupsk), Comparison of some families of real functions in porosity terms
  • 2018-12-11: Jacek Tryba, A note on nonregular matrices and ideals associated with them
  • 2018-12-04: Marcin Szyszkowski, Matrices of projections and their diagonals – how to connect them in measurable way
  • 2018-11-27: A seminar dedicated to the 95th birthday of Professor Lipiński
  • 2018-11-20: Edward Grzegorek, On σ-algebras closed under Souslin’s operation
  • 2018-11-13: Rafał Filipów, Abstract densities and ideals of sets
  • 2018-11-06: Stanisław Kowalczyk (Pomeranian University in Słupsk), Multiplication in the space of functions of bounded variation (continuation)
  • 2018-10-30: Stanisław Kowalczyk (Pomeranian University in Słupsk), Multiplication in the space of functions of bounded variation
  • 2018-10-23: Adam Ostaszewski (London School of Economics, UK), Centenary of the Steinhaus(-Weil) Theorem: A sneak preview
  • 2018-10-16: Adam Kwela, Marcin Staniszewski, Size of the set of attractors for iterated function systems (continuation)
  • 2018-10-09: Adam Kwela, Marcin Staniszewski, Size of the set of attractors for iterated function systems
  • 2018-06-19: Paweł Klinga, Attractors for iterated function systems form an Fσ set
  • 2018-06-12: Adam Kwela, Haar-smallest sets (continuation)
  • 2018-06-05: Adam Kwela, Haar-smallest sets
  • 2018-05-29: Robert Rałowski (Wroclaw University of Science and Technology), Nonmeasurable sets and unions with respect to tree ideals
  • 2018-05-22: Piotr Szuca, Attractors for iterated function schemes on [0,1]N are exceptional (continuation)
  • 2018-05-15: Marcin Staniszewski, Attractors for iterated function schemes on [0,1]N are exceptional
  • 2018-05-08: Wojciech Wołoszyn, Fusion-type forcings (continuation)
  • 2018-04-24: Wojciech Wołoszyn, Fusion-type forcings
  • 2018-04-17: Waldemar Sieg (Casimir the Great University in Bydgoszcz), Sets of convergence points of sequences of functions with a closed graph (continuation)
  • 2018-04-10: Waldemar Sieg (Casimir the Great University in Bydgoszcz), Sets of convergence points of sequences of functions with a closed graph (continuation)
  • 2018-03-27: Adam Ostaszewski (London School of Economics, UK), Some generalizations of Steinhaus theorem by Raikov and Świątkowski
  • 2018-03-13: Waldemar Sieg (Casimir the Great University in Bydgoszcz), Sets of convergence points of sequences of functions with a closed graph
  • 2018-03-06: Rafał Filipów, Intersections of matrix summability methods in the realm of bounded and unbounded sequences
  • 2018-02-27: Rafał Filipów, Unions of matrix summability methods in the realm of bounded and unbounded sequences
  • 2018-02-20: Tomasz Natkaniec, Convergent subsequences of a divergent sequence of functions
  • 2018-01-23: Edward Grzegorek, On some old results of Karel Prikry about partitions into null sets
  • 2018-01-16: Michał Popławski (Lodz University of Technology), Ideal convergence of subseries from the measure viewpoint
  • 2018-01-09: Nikodem Mrożek, On ideal cluster points and ideal limit points

2017

  • 2017-12-19: Edward Grzegorek, On two theorems of Sierpiński
  • 2017-12-12: Adam Kwela, Ideal weak QN-spaces
  • 2017-12-05: Szymon Żeberski (Wroclaw University of Science and Technology), On applications of Shoenfield absoluteness theorem
  • 2017-11-28: Klaudiusz Czudek (Institute of Mathematics of the Polish Academy of Sciences) , Invariant measures for random interval homeomorphisms
  • 2017-11-21: Jakub Jasiński (University of Scranton, USA), Fixed and periodic points of locally contracting maps
  • 2017-11-14: Wojciech Wołoszyn, V = Ultimate L
  • 2017-11-07: Piotr Szuca, On Darboux-Baire one composition problem
  • 2017-10-24: Adam Ostaszewski (London School of Economics, UK), Additivity and subadditivity in the light of asymptotic group action
  • 2017-10-17: Tomasz Natkaniec, Perfectly everywhere surjective but not Jones functions (continuation)
  • 2017-10-10: Tomasz Natkaniec, Perfectly everywhere surjective but not Jones functions
  • 2017-07-20: Wiesław Kubiś (Institute of Mathematics of the Czech Academy of Sciences and Cardinal Stefan Wyszyński University in Warsaw), Universal homogeneous probability measure on the Cantor set
  • 2017-06-13: Pratulananda Das (Jadavpur University, India), Some remarks on open covers and selection principles using ideals
  • 2017-06-06: Michał Małafiejski (Gdansk University of Technology), Generalization of Hales–Jewett theorem (continuation)
  • 2017-05-23: Jacek Tryba, Dense difference sets and their combinatorial structure
  • 2017-05-16: Jacek Tryba, Various problems on densities (continuation)
  • 2017-05-09: Jacek Tryba, Various problems on densities
  • 2017-04-25: Marek Balcerzak (Lodz University of Technology), Baire category of ideal convergent subseries and permutations
  • 2017-04-11: Adam Ostaszewski (London School of Economics), Walk on the real line: stable distributions versus functional equations
  • 2017-04-04: Michał Małafiejski (Gdansk University of Technology), Generalization of Hales–Jewett theorem (continuation)
  • 2017-03-28: Michał Małafiejski (Gdansk University of Technology), Generalization of Hales–Jewett theorem
  • 2017-03-21: Adam Kwela, Simple density ideals (continuation)
  • 2017-03-14: Adam Kwela, Simple density ideals
  • 2017-03-07: Jacek Tryba, Simple density ideals
  • 2017-02-28: Tomasz Natkaniec, Pointwise limits of sequences of Świątkowski functions (continuation)
  • 2017-02-21: Tomasz Natkaniec, Pointwise limits of sequences of Świątkowski functions (continuation)
  • 2017-02-14: Adam Ostaszewski (London School of Economics, UK), Category-measure duality: convexity, mid-point convexity and Berz sublinearity
  • 2017-01-24: Tomasz Natkaniec, Pointwise limits of sequences of Świątkowski functions
  • 2017-01-17: Waldemar Sieg (Casimir the Great University in Bydgoszcz), P-spaces and an unconditional closed graph theorem (continuation)
  • 2017-01-10: Waldemar Sieg (Casimir the Great University in Bydgoszcz), P-spaces and an unconditional closed graph theorem

2016

  • 2016-12-20: Marta Frankowska, Symmetric density points in the Cantor set
  • 2016-12-06: Piotr Szuca, On extensions of asymptotic density
  • 2016-11-29: Jacek Tryba, On extensions of asymptotic density
  • 2016-11-22: Nikodem Mrożek, Katetov and Katetov-Blass orders on Fσ-ideals
  • 2016-11-15: Jacek Tryba, Ideal convergence versus matrix summability
  • 2016-11-08: Rafał Filipów, Intersection of matrix summability methods (continuation)
  • 2016-10-25: Adam Ostaszewski (London School of Economics, UK), On theorem of Effros about micro-transitive actions on Baire groups
  • 2016-10-18: Rafał Filipów, Intersection of matrix summability methods (continuation)
  • 2016-10-11: Rafał Filipów, Intersection of matrix summability methods
  • 2016-06-14: Klaudiusz Czudek, Bernstein and Kantorovitch polynomials
  • 2016-06-07: Marcin Szyszkowski, Separating sets with Gδ (and Fσ) sets
  • 2016-05-31: Klaudiusz Czudek, Superposition operators in the space of functions of bounded variation
  • 2016-05-24: Julia Wódka (Lodz University of Technology), Uniform limits of sequences of Świątkowski functions
  • 2016-05-17: Nikodem Mrożek, Dominated Convergence and Egorov Theorems for Filter Convergence (continuation)
  • 2016-05-10: Nikodem Mrożek, Dominated Convergence and Egorov Theorems for Filter Convergence
  • 2016-04-26: Paulina Szczuka (Casimir the Great University in Bydgoszcz), Topological and algebraic properties of Darboux-like and pointwise discontinuous functions
  • 2016-04-19: Jacek Tryba, Darboux property for weighted uniform densities (continuation)
  • 2016-04-12: Jacek Tryba, Darboux property for weighted uniform densities
  • 2016-04-05: Adam Ostaszewski (London School of Economics, UK), On the Steinhaus property
  • 2016-03-22: Jacek Tryba, Ideal invariant injections
  • 2016-03-15: Adam Kwela, Homogeneous and hereditarily homogeneous ideals
  • 2016-03-08: Paulina Szczuka (Casimir the Great University in Bydgoszcz), Topologies on the integers generated by arithmetic progressions
  • 2016-03-01: Adam Kwela, Ideal invariant injections with large sets of fixed points
  • 2016-02-23: Klaudiusz Czudek, Generalized bounded variation
  • 2016-02-16: Waldemar Sieg (Casimir the Great University in Bydgoszcz), Extensions of some Baire one functions (continuation)
  • 2016-01-19: Waldemar Sieg (Casimir the Great University in Bydgoszcz), Extensions of some Baire one functions
  • 2016-01-12: Marcin Staniszewski, Quasi-normal convergence of sequences of quasi-continuous functions (continuation)
  • 2016-01-05: Marcin Staniszewski, Quasi-normal convergence of sequences of quasi-continuous functions (continuation)

2015

  • 2015-12-15: Marcin Staniszewski, Quasi-normal convergence of sequences of quasi-continuous functions (continuation)
  • 2015-12-08: Marcin Staniszewski, Quasi-normal convergence of sequences of quasi-continuous functions (continuation)
  • 2015-12-01: Marcin Staniszewski, Quasi-normal convergence of sequences of quasi-continuous functions (continuation)
  • 2015-11-24: Marcin Staniszewski, Quasi-normal convergence of sequences of quasi-continuous functions
  • 2015-11-17: Rafał Filipów, Two ideals not fulfilling Fatou’s lemma: Solecki’s ideal and finite coloring ideal
  • 2015-11-10: Marcin Staniszewski, Quasi-normal convergence of sequences of continuous functions (continuation)
  • 2015-11-03: Marcin Staniszewski, Quasi-normal convergence of sequences of continuous functions
  • 2015-10-27: Adam Ostaszewski (London School of Economics, UK), The sound of silence: filtering and optimal censorship in the market (Krzyk ciszy: filtrowanie i optymalna cenzura w rynkach finansowych)
  • 2015-10-20: Jacek Tryba, A matrix characterization of statistical convergence (Mazur’s problem from The Scottish Book)
  • 2015-10-13: Jacek Tryba, On modified Olivier’s theorem for some idelas
  • 2015-10-05: Szymon Głąb (Politechnika Łódźka), Duże wolne podgrupy grup automorfizmów przestrzeni ultrahomogenicznych
  • 2015-06-09: Marcin Staniszewski, O zbieżności ideałowej (kontynuacja); Jacek Tryba, O pewnym rodzaju zbieżności ciągów zdefiniowanym przy pomocy f-gęstości
  • 2015-06-02: Marcin Staniszewski, O zbieżności ideałowej (kontynuacja)
  • 2015-05-26: Adam Ostaszewski (London School of Economics, UK), Homeomorphisms from functional equations in probability
  • 2015-05-19: Marcin Staniszewski, O zbieżności ideałowej (kontynuacja)
  • 2015-05-12: Marcin Staniszewski, O zbieżności ideałowej
  • 2015-05-05: Adam Kwela, O addytywności zbiorów mikroskopijnych (kontynuacja)
  • 2015-04-28: Adam Kwela, O addytywności zbiorów mikroskopijnych
  • 2015-04-21: Piotr Szuca, Uogólnienie gęstości asymptotycznej (kontynuacja)
  • 2015-04-14: Piotr Szuca, Uogólnienie gęstości asymptotycznej (kontynuacja)
  • 2015-03-31: Piotr Szuca, Uogólnienie gęstości asymptotycznej
  • 2015-03-24: Paweł Klinga, Ideałowa wersja twierdzenia Riemanna
  • 2015-03-17: Jacek Tryba, Ideałowa zbieżność szeregów liczbowych (kontynuacja)
  • 2015-03-10: Jacek Tryba, Ideałowa zbieżność szeregów liczbowych
  • 2015-03-03: Paweł Barbarski, Zrandomizowane twierdzenie Szarkowskiego (kontynuacja)
  • 2015-02-24: Paweł Barbarski, Zrandomizowane twierdzenie Szarkowskiego (kontynuacja)
  • 2015-01-27: Paweł Barbarski, Zrandomizowane twierdzenie Szarkowskiego (kontynuacja)
  • 2015-01-20: Paweł Barbarski, Zrandomizowane twierdzenie Szarkowskiego
  • 2015-01-13: Adam Kwela, Zbiory mikroskopijne (kontynuacja)

2014

  • 2014-12-16: Adam Kwela, Zbiory mikroskopijne
  • 2014-12-09: Nikodem Mrożek, Zbiory mikroskopijne
  • 2014-12-02: Paweł Klinga, Funkcje osiowe i ideały na ℕ II
  • 2014-11-25: Waldemar Sieg (Uniwersytet Kazimierza Wielkiego w Bydgoszczy, Poland), Rozkłady i przedłużenia pewnych funkcji pierwszej klasy Baire’a
  • 2014-11-18: Rafał Filipów, Zbieżność quasi-normalna i punktowa ciągów funkcyjnych II (kontynuacja)
  • 2014-11-04: Rafał Filipów, Zbieżność quasi-normalna i punktowa ciągów funkcyjnych II (kontynuacja)
  • 2014-10-28: Rafał Filipów, Zbieżność quasi-normalna i punktowa ciągów funkcyjnych II
  • 2014-10-21: Adam Kwela, Selektywność ideałów, a ich gęstość (kontynuacja)
  • 2014-10-14: Adam Kwela, Selektywność ideałów, a ich gęstość
  • 2014-05-27: Rafał Filipów, Zbieżność quasi-normalna i punktowa ciągów funkcyjnych
  • 2014-05-20: Jacek Tryba, Zbieżność w przestrzeniach Hindmana i van der Waerdena (kontynuacja)
  • 2014-05-13: Jacek Tryba, Zbieżność w przestrzeniach Hindmana i van der Waerdena
  • 2014-05-06: Rafał Filipów, Granice Banacha i granice statystyczne
  • 2014-04-29: Paweł Klinga, Funkcje osiowe i ideały na ℕ
  • 2014-04-15: Adam Kwela, Przykład ideału typu Fσ (kontynuacja)
  • 2014-04-08: Adam Kwela, Przykład ideału typu Fσ (kontynuacja)
  • 2014-04-01: Adam Kwela, Przykład ideału typu Fσ
  • 2014-03-18: Piotr Szuca, A-statistical cluster points in finite dimensional spaces and application to turnpike theorem (kontynuacja)
  • 2014-02-25: Paweł Barbarski, Pierścienie funkcji Szarkowskiego (kontynuacja)
  • 2014-02-18: Paweł Barbarski, Pierścienie funkcji Szarkowskiego
  • 2014-01-21: Piotr Szuca,  A-statistical cluster points in finite dimensional spaces and application to turnpike theorem (kontynuacja)
  • 2014-01-14: Piotr Szuca,  A-statistical cluster points in finite dimensional spaces and application to turnpike theorem
  • 2014-01-07: Marcin Staniszewski, Zbieżność punktowa, dyskretna i quasi-normalna ciągów funkcji quasi ciągłych (kontynuacja)

2013

  • 2013-12-17: Marcin Staniszewski, Zbieżność punktowa, dyskretna i quasi-normalna ciągów funkcji quasi ciągłych