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Abstracts for Oberseminar Differentialgeometrie

Alternatively have a look at the program.

Uniqueness of the contact structure approximating a foliation

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Speaker: 
Thomas Vogel
Affiliation: 
MPI
Date: 
Thu, 2013-04-11 16:30 - 17:30
Location: 
MPIM Lecture Hall

According to a theorem of Eliashberg and Thurston a C2-foliation on a closed 3-manifold can be C0-approximated by contact structures unless all leaves of the foliation are spheres. Examples on the 3-torus show that every neighbourhood of  a foliation can contain
infinitely many non-diffeomorphic contact structures. In this talk we show that this is rather exceptional: In many interesting situations the contact structure in a sufficiently small

Low dimensional collapsing theory and soul theorem for Alexandrov spaces

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Speaker: 
Jian Ge
Affiliation: 
Dotre Dame
Date: 
Thu, 2013-04-18 16:30 - 17:30
Location: 
MPIM Lecture Hall
In this talk we will give an overview of the collapsing theory for 3-dimensional manifolds with a lower sectional curvature bound. This theory first developed by Shioya and Yamaguchi served as the completion of the last claim in Perelman's Proof of Geometrization Conjecture. The basic techniques used in the study will be presented with emphasis on Perelman's Fibration Theorem and Soul Theorem. Collapsing theory with bounded sectional curvature will also be quickly reviewed so that we can see the differences/parallel structures between these two theory.

Representations from a metric point of view

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Speaker: 
Alexander Lytchak
Affiliation: 
Universität zu Köln
Date: 
Thu, 2013-05-16 16:30 - 17:30
Location: 
MPIM Lecture Hall

In the talk I will discuss metric properties of  quotient spaces of representations of compact groups
on Euclidean spaces.

Analytic construction of dihedral A.L.F. gravitational instantons

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Speaker: 
Hugues Auvray
Date: 
Thu, 2013-06-27 16:30 - 17:30
Location: 
MPIM Lecture Hall

Calabi-Yau Conjecture for Minimal Surfaces

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Speaker: 
Baris Coskunuzer
Affiliation: 
KOC Univ. Istanbul/MPI
Date: 
Thu, 2013-07-18 16:30 - 17:30
Location: 
MPIM Lecture Hall
In this talk, I will first give an outline of the current state of the Calabi-Yau Conjecture, which asserts that any complete, embedded minimal surface in R^3 must be properly embedded. Then, I will give a construction of a counterexample in H^3.

The geometry of biinvariant word metrics

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Speaker: 
Jaroslaw Kedra
Affiliation: 
U of Aberdeen
Date: 
Thu, 2013-10-31 16:30 - 17:30
Location: 
MPIM Lecture Hall
Let G be a normally finitely generated group and let |g| be the
conjugation invariant word norm of an element g of G. We are interested in
the growth rate of the function n --> |g^n|. A priori this can be anything
between bounded and linear. I will show that for many classes of groups
there is a dichotomy: |g^n| is either bounded or linear.

Construction of surfaces with large systolic ratio

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Speaker: 
Bjoern Muetzel
Affiliation: 
University Montpellier 2
Date: 
Thu, 2013-12-12 16:30 - 17:30
Location: 
MPIM Lecture Hall

The long-time evolution of three-dimensional Ricci flow

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Speaker: 
John Lott
Date: 
Thu, 2014-01-09 16:30 - 17:30
Location: 
MPIM Lecture Hall

Coarse topology of leaves of foliations

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Speaker: 
Robert Schmidt
Affiliation: 
LMU München
Date: 
Thu, 2014-01-23 16:30 - 17:30
Location: 
MPIM Lecture Hall

On isoparametric hypersurfaces

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Speaker: 
Uwe Abresch
Affiliation: 
Ruhr U Bochum
Date: 
Thu, 2014-01-30 16:30 - 17:30
Location: 
MPIM Lecture Hall
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