Talks and events


Upcoming talks

[mathematikon] Tue 24.10.2017, Phys 2.52 at 12h15

Ivan Izmestiev: Schliessungsätze

Please find the abstract here.

[colloque] Tue 24.10.2017, Phys 2.52 at 17h15

Prof. Omid Amini (CNRS - Ecole Normale Supérieure Paris): Graph theory in arithmetic and algebraic geometry

Despite their simplicity of nature, graphs are among the richest mathematical objects whose links to other branches of mathematics constantly surprise.

In this talk, I will aim to explain how some concepts which have shaped the development of modern graph theory appear naturally in algebraic geometry, in the study of the space of solutions of systems of polynomial equations. I will discuss two themes: geometric universality of graphs and control of arithmetic points of algebraic curves.

[oberseminar] Oberseminar Topologie, Mon 30.10.2017, Math II (Lonza) at 16h00

Michael Joachim (Münster): Twisted spin^c bordism and twisted K-homology

In our talk we present a twisted analogue of a result of Hopkins and Hovey who show that the functor which associates to a space $X$ the graded abelian group $\Omega^{spin}_{*}(X) \otimes_{\Omega^{spin}_{*}} KO_{*}(pt)$ yields a geometric description of $KO_{*}(X)$. Our analogue for twisted $K$-theory also gives further inside to a Brown-Douglas approach to twisted $K$-homology. The results are joint work with Baum, Khorami and Schick.

[colloque] Tue 7.11.2017, Phys 2.52 at 17h15

Prof. Christine Bachoc (Bordeaux): Sets avoiding the distance 1 in $\mathbb R^n$

What is the supremum density of a measurable set in $\mathbb R^n$ avoiding distance 1? If the distance is the Euclidean distance, the answer is known only in the trivial case n = 1. This problem is closely related to that of the determination of the chromatic number of the Euclidean space, a surprisingly difficult problem even in dimension 2, which is open since it was posed by Nelson and Hadwiger in 1950. We will discuss recent results obtained on this question and also on several variants that rely on a combination of methods from convex optimization and Fourier analysis. In one of these variants, one replaces the Euclidean norm by a norm defined by a convex symmetric polytope. When the polytope tiles the space by translations, we conjecture that the answer is $\mathbb 1/2^n$ and that the proof should be much easier that in the Euclidean setting. We will present a proof of this conjecture in dimension 2 and discuss a few other cases of Voronoi polytopes associated to lattices.

[colloque] Tue 14.11.2017, Phys 2.52 at 17h15

Prof. Yohei Komori (Waseda Univ, Tokyo): Growth functions of hyperbolic groups

[oberseminar] Oberseminar Topologie, Mon 27.11.2017, Math II (Lonza) at 16h15

Masoumeh Zarei (Peking Uni.): Equivariant classification of cohomogeneity one Alexandrov spaces in low dimension

In this talk, I will give an equivariant classification of cohomogeneity one Alexandrov spaces in dimensions 5; 6 and 7. As a result, we show that all orbifolds appeared in the classification are equivariantly homeomorphic to a smooth good orbifold of cohomogeneity one. Furthermore, I will discuss a characterization of cohomogeneity one Alexandrov spaces to be topological manifolds. In particular, we prove that such spaces are homeomorphic to smooth manifolds in low dimensions. This is a joint work with Fernando Galaz-Garcia.

[colloque] Tue 28.11.2017, Phys 2.52 at 17h15

Prof. Urs Lang (ETHZ): tba

[colloque] Tue 5.12.2017, Phys 2.52 at 17h15

Prof. Valentin Féray (Uni Zürich): tba

[colloque] Tue 12.12.2017, Phys 2.52 at 17h15

Prof. Maryna Viazovska (EPFL): tba

[colloque] Tue 19.12.2017, Phys 2.52 at 17h15

Sophie Hautphenne (Melbourne / EPFL): tba


Colloquia in the current semester

[colloque] Tue 1.3.2016, Phys 2.52 at 17h15 - Festvortrag zum 80. Geburtstag von Ernst Ruhmore

Prof. Dr. Ernst Heintze (Uni Augsburg): Affine root systems and submanifolds of Hilbert spaces

[colloque] Tue 8.3.2016, Phys 2.52 at 17h15more

Prof. Joan Porti (Barcelona): Reidemeister torsion and hyperbolic 3-manifolds

[colloque] Tue 22.3.2016, Phys 2.52 at 17h15more

Prof. Uwe Semmelmann (Uni. Stuttgart): Invariant 4-forms and exceptional Lie algebras

[colloque] Tue 12.4.2016, Phys 2.52 at 17h15more

Prof. Dr. Benjamin Sudakov (ETH Zürich): Induced matchings, arithmetic progressions and communication

[colloque] Tue 19.4.2016, Phys 2.52 at 17h15more

Prof. Christophe Bavard (Bordeaux): Points conjugués en géométrie riemannienne et lorentzienne

[colloque] Tue 26.4.2016, Phys 2.52 at 17h15more

Prof. Roman Sauer (KIT): Invariant random subgroups

[colloque] Tue 3.5.2016, Phys 2.52 at 17h15more

Prof. Hans Josef Pesch (Uni Bayreuth): Optimal Control of Dynamical Systems Governed by Partial Differential Equations

[colloque] Tue 10.5.2016, Phys 2.52 at 17h15more

Prof. Sergiu Moroianu (Bucharest): Renormalized volume in hyperbolic geometry

[colloque] Tue 17.5.2016, Phys 2.52 at 17h15more

Prof. Vincent Beffara (CNRS Grenoble): Introduction to the Schramm-Loewner Evolution

[colloque] Tue 24.5.2016, Phys 2.52 at 17h15more

Dr. Roger Zuest (Fribourg): Regularity theory for almost minimal surfaces

[colloque] Tue 31.5.2016, Phys 2.52 at 17h15more

Prof. Wolfgang Lück (Universität Bonn / HIM Bonn): Introduction to $L^2$-Betti numbers

[colloque] Tue 7.6.2016, Phys 2.52 at 15h30more

Prof. Alexandru Suciu (Northeastern University, Boston): Fundamental groups in algebraic geometry and three-dimensional topology

[colloque] Tue 20.9.2016, Phys 2.52 at 17h15more

Prof. Daniel Grieser (Universität Oldenburg): A look at triangles from elementary geometry, spectral theory and singular analysis

[colloque] Tue 27.9.2016, Phys 2.52 at 17h15more

Prof. Christoph Böhm (Universität Münster): Immortal homogeneous Ricci flows

[colloque] Tue 11.10.2016, Phys 2.52 at 17h15more

Prof. Gerhard Opfer (Universität Hamburg): Zeros of unilateral quaternionic and coquaternionic polynomials

[colloque] Tue, 25.10.2016, Phys 2.52 at 17h15more

Dr. Wim Hordijk (Konrad Lorenz Institut, Klosterneuburg): Autocatalytic Sets: The Origin and Organization of Life

[colloque] Tue 8.11.2016, Phys 2.52 at 17h15more

Prof. Manfred Lehn (JG Universität Mainz): The theorem of Grothendieck-Brieskorn-Slodowy and symplectic singularities

[colloque] Tue 15.11.2016, Phys 2.52 at 17h15more

Prof. Nicolas Curien (Université Paris-Sud Orsay): A panoramic introduction to random planar maps

[colloque] Tue 22.11.2016, Phys 2.52 at 17h15more

Prof. Masahiko Yoshinaga (Hokkaido University): Characteristic polynomials of hyperplane arrangements

[colloque] Tue 6.12.2016, Phys 2.52 at 17h15more

Prof. Priyam Patel (UCSB): Quantitative methods in hyperbolic geometry

[colloque] Tue 13.12.2016, Phys 2.52 at 17h15more

Prof. Christophe Soulé (IHES): La théorie d'Arakelov

[colloque] Tue 7.3.2017, Phys 2.52 at 17h15more

Prof. Sergei Tabachnikov (Pennsylvania State University): Skewers

[colloque] Tue 14.3.2017, Phys 2.52 at 17h15more

Prof. Philipp Habegger (Uni Basel): Complex Multiplication or is $e^{\pi \sqrt{163}}$ an Integer?

[colloque] Tue 21.3.2017, Phys 2.52 at 17h15more

Prof. Jan Draisma (Uni Bern): Stabilisation in algebra and geometry

[colloque] Tue 28.03.2017, Phys 2.52 at 17h15more

Martin Kerin (Univ. of Münster): Curvature and exotic spheres

[colloque] Tue 4.4.2017, Phys 2.52 at 17h15more

Prof. Armin Iske (Uni Hamburg): Kernel-based Scattered Data Approximation

[colloque] Tue 25.4.2017, Phys 2.52 at 17h15more

Prof. Antti Knowles (Uni Genève): Extreme eigenvalues of sparse random graphs

[colloque] Tue 16.5.2017, Phys 2.52 at 17h15more

Prof. Pierre Nolin (ETHZ): Near-critical percolation and self-organized criticality in two dimensions

[colloque] Tue 30.5.2017, Phys 2.52 at 17h15more

Prof. Gerhard Wanner (Uni Genève): Porous media modelling with a 250 years old method

Other talks and events in the current semester

[oberseminar] Oberseminar Geometrie, Wed 4.3.2015, Math II (Lonza) at 10:20more

Martin Herrmann (Fribourg): Almost nonnegative curvature operator, homogeneous spaces and a question of Karsten Grove

[oberseminar] Oberseminar Geometrie, Wed 11.3.2015, Math II (Lonza) at 10:20more

Mike Roberts (Durham): A methodical approach to the construction of Coxeter polytopes in hyperbolic n-space with n+3 facets

[oberseminar] Combinatorics seminar, Fri 13.3.2015, Math II (Lonza) at 13:15more

Ornella greco (KTH Stockholm): The Betti table of Veronese Modules

[oberseminar] Oberseminar Geometrie, Wed 18.3.2015, Math II (Lonza) at 10:20more

Kate Juschenko (Northwestern): Techniques and concepts of amenability of discrete groups

[oberseminar] Oberseminar Geometrie, Wed 26.3.2015, Math II (Lonza) at 10:20more

Stefan Rosemann (Jena): Kähler metrics with Hamiltonian 2-forms, their classification via projectively equivalent metrics and applications

[oberseminar] Oberseminar Geometrie, Wed 15.4.2015, Math II (Lonza) at 10:20more

Bernhard Mühlherr (Giessen): Tits-indices, affine Coxeter groups and buildings

[oberseminar] Oberseminar Geometrie, Wed 22.4.2015, Math II (Lonza) at 10:20more

Viktoriya Ozornova (Bremen / MPIM Bonn): Factorability structures

[oberseminar] Combinatorics seminar, Fri 24.04.2015, Time and place TBAmore

Matteo Varbaro (Genova): On dual graphs of complete intersections

[oberseminar] Oberseminar Geometrie, Wed 29.4.2015, Math II (Lonza) at 10:20more

Jordane Granier (Fribourg): Sous-groupe discret de PU(2,1) avec l'éponge de Menger pour ensemble limite

[oberseminar] Oberseminar Geometrie, Wed 6.5.2015, Math II (Lonza) at 10:20more

Vincent Emery (EPF Lausanne): Volumes des variétés hyperboliques et actions de Galois

[oberseminar] Oberseminar Geometrie, Wed 20.5.2015, Math II (Lonza) at 10:20more

Misha Wasem (ETHZ): Isometric extensions at low regularity and codimension

[oberseminar] Oberseminar Geometrie, Wed 27.5.2015, Math II (Lonza) at 10:20more

Martin Deraux (Grenoble): Groupes de triangles en géométrie hyperbolique complexe

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