Talks and events

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Upcoming talks

[colloque] Tue 20.2.2018, Phys 2.52 at 17h15

Prof. Alexandre Stauffer (University of Bath): Spatial growth processes: dendritic formation and competition

This talk focuses on a classical growing process, called multi-particle diffusion-limited aggregation (MDLA), where growth is governed by the aggregation of moving particles. This model was introduced in the physics literature in 1980 with the goal of providing an example of “a simple and tractable” mathematical model of dendritic growth, which (similar to what has been observed in nature) produces a delicate, fractal-like geometry. Almost four decades later we still encounter tremendous mathematical challenges studying its geometric and dynamic properties, and understanding the driving mechanism lying behind the formation of fractal-like structures. In this talk, I will survey the developments in this field, giving emphasis to a new process, based on the competition of two growing systems, which we introduce and use to better understand MDLA. This is based on joint works with Elisabetta Candellero and Vladas Sidoravicius.

[oberseminar] Oberseminar Geometrie, Wed 21.02.2018, Math II (Lonza) at 10h20

Corina Ciobotaru (Fribourg): Applications of hyperbolic geometry to Kuramoto model of synchronization

The Kuramoto model of synchronization is a mathematical model describing the phenomenon of self-synchronization in large systems of interacting oscillatory elements. Examples include synchronization of cardiac pacemaker cells, firefly populations, electro-chemical oscillations, synchronization of people walking, etc… Those phenomena are modelled via a system of ordinary differential equations (the Kuramoto model) and the solution to this o.d.e ‘converges’ with time to an equilibrium point, the synchronisation of the system. Amazingly, the equilibrium point is linked to the hyperbolic geometry on the Poincaré disc model and the Moebius transformations. By employing the four different models for the hyperbolic plane, in the recent joint work with Hoessly—Mazza—Richard, we unify and clarify various aspects of the Kuramoto model previously existed in the literature.

[colloque] Tue 6.3.2018, Phys 2.52 at 17h15

Prof. Jan Maas (IST Austria): tba

[oberseminar] Combinatorics Seminar, Wed 7.3.2018, Math II (Lonza) at 14h00

Enrico Cecini (Genoa): tba

[oberseminar] Oberseminar Topologie, Mon 12.03.2018, Math II (Lonza) at 16h00

Uwe Semmelmann (Stuttgart): The kernel of the Rarita-Schwinger operator on Riemannian spin manifolds

[colloque] Tue 13.3.2018, Phys 2.52 at 17h15

Prof. Florian Bertrand (University of Beyrouth): tba

[oberseminar] Oberseminar Topologie, Monday 19.03.2018, Math II (Lonza) at 16h00

Jan-Bernhard Kordass (Karlsruhe): Spaces of Riemannian Metrics satisfying Surgery Stable Curvature Conditions

In an effort to extend a well-known result by V. Chernysh and M. Walsh, we explore the notion of a surgery stable curvature condition as suggested by the work of S. Hoelzel. We will sketch the construction of a deformation map, which allows to continuously alter a riemannian metric to a certain prescribed one in a small neighbourhood of an embedded submanifold, while curvature conditions are controlled. Moreover, we will comment on disconnectedness properties for spaces of metrics satisfying several curvature conditions and explain an application to highly-connected manifolds.

[colloque] Tue 20.3.2018, Phys 2.52 at 17h15

Prof. Jean-Marc Schlenker (Luxembourg): tba

[oberseminar] Combinatorics Seminar, Wed 21.3.2018, Math II (Lonza) at 14h00

Viola Siconolfi (Roma): tba

[oberseminar] Oberseminar Topologie, Monday 26.03.2018, Math II (Lonza) at 16h00

Raphael Zentner (Regensburg/FIM): Irreducible SL(2,C)-representations of integer homology 3-sphere

We prove that the splicing of any two non-trivial knots in the 3-sphere admits an irreducible SU(2)-representation of its fundamental group. This uses instanton gauge theory, and in particular a non-vanishing result of Kronheimer-Mrowka and some new results that we establish for holonomy perturbations of the ASD equation. Using a result of Boileau, Rubinstein and Wang (which builds on the geometrization theorem of 3-manifolds), it follows that the fundamental group of any integer homology 3-sphere different from the 3-sphere admits irreducible representations of its fundamental group in SL(2,C).

[colloque] Tue 10.4.2018, Phys 2.52 at 17h15

Prof. Pierre Pansu (Université Paris-Sud Orsay): tba

[colloque] Tue 1.5.2018, Phys 2.52 at 17h15

Prof. Bernard Ries (Uni Fribourg): tba

[colloque] Tue 8.5.2018, Phys 2.52 at 17h15

Prof. Luis Guijarro (Universidad Autónoma de Madrid): tba

[colloque] Tue 15.5.2018, Phys 2.52 at 17h15

Prof. Andrea Mondino (Warwick): tba

[colloque] Tue 22.5.2018, Phys 2.52 at 17h15

Prof. Stéphane Loisel (ISFA Lyon): tba

Archive:

Colloquia in the current semester

[colloque] Tue 3.10.2017, Phys 2.52 at 17h15more

Prof. Manfred Trummer (Simon Fraser University Vancouver): Reconstruction of Dynamic SPECT Images

[colloque] Tue 17.10.2017, Phys 2.52 at 17h15more

Prof. Jamal Najim (Université de Marne La Vallée): Large Random Matrices of Long Memory Stationary Processes: Asymptotics and fluctuations of the largest eigenvalue

[colloque] Tue 24.10.2017, Phys 2.52 at 17h15more

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

[colloque] Tue 7.11.2017, Phys 2.52 at 17h15more

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

[colloque] Tue 14.11.2017, Phys 2.52 at 17h15more

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

[colloque] Tue 28.11.2017, Phys 2.52 at 17h15more

Prof. Urs Lang (ETHZ): Higher rank hyperbolicity in spaces of nonpositive curvature

[colloque] Tue 5.12.2017, Phys 2.52 at 17h15more

Prof. Valentin Féray (Uni Zürich): What do random constraint permutations look like?

[colloque] Tue 12.12.2017, Phys 2.52 at 17h15more

CANCELLED - Prof. Maryna Viazovska (EPFL): The sphere packing problem in dimensions 8 and 24

Other talks and events in the current semester

[oberseminar] Oberseminar Topologie, Mon 18.09.2017, Math II (Lonza) at 16h00more

David González Álvaro (Fribourg): Non-negative sectional curvature on stable classes of vector bundles

[oberseminar] Wed 27.09.2017, Math II (Lonza) at 10h20more

Grigory Ivanov (EPFL): The cross-polytope and the cube, their sections and projections

[oberseminar] Oberseminar Topologie, Mon 02.10.2017, Math II (Lonza) at 16h00more

Anand Dessai (Fribourg): Topology of moduli spaces of nonnegative curved metrics and eta-invariants

[oberseminar] Wed 04.10.2017, Math II (Lonza) at 10h20more

Stephan Klaus (MFO): Dihedral angles and combinatorial Gauss-Bonnet Theorem

[oberseminar] Wed 11.10.2017, Math II (Lonza) at 10:20more

Yuri Suris (TU Berlin): On a discretization of confocal quadrics

[mathematikon] Tue 24.10.2017, Phys 2.52 at 12h15more

Ivan Izmestiev: Schliessungsätze

[oberseminar] Oberseminar Topologie, Mon 30.10.2017, Math II (Lonza) at 16h00more

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

[oberseminar] Oberseminar Topologie, Mon 27.11.2017, Math II (Lonza) at 16h15more

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

[oberseminar] Oberseminar Geometrie, Wed 29.11.2017, Math II (Lonza) at 10h20more

Plinio G. P. Murillo (Bern): Hyperbolic manifolds with large systole

[oberseminar] Oberseminar Topologie, Mon 04.12.2017, Math II (Lonza) at 16h00more

Michael Wiemeler (Münster): On the topology of moduli spaces of non-negative Ricci-curved metrics

[oberseminar] Oberseminar Geometrie, Wed 06.12.2017, Math II (Lonza) at 10h20more

David González Álvaro (Fribourg): Manifolds with positive sectional curvature

[oberseminar] Oberseminar Geometrie, Wed 13.12.2017, Math II (Lonza) at 10h20more

Florian Besau (Frankfurt): Floating bodies in spherical and hyperbolic geometry

[oberseminar] Oberseminar Topologie, Mon 18.12.2017, Math II (Lonza) at 16h00 more

Manuel Amann (Augburg): Orbifolds with all geodesics closed

[oberseminar] Oberseminar Geometrie, Wed 20.12.2017, Math II (Lonza) at 10h20more

Roman Prosanov (Fribourg): Covering problems in discrete geometry

Université de Fribourg - Mathématiques - Ch. du Musée 23, 1700 Fribourg - tél +41 26 / 300 9180      isabella.schmutz@unifr.ch
Last modified on Dec 18, 2017    Webmasters: Sophie Schneider, Simon Drewitz