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Auteur(s) Bodin Arnaud (145) Blanc-Centi Léa (115) RECHENMANN Francois (52) MEUNIER Jean-Marc (25) Borne Niels (19) Desideri Laura (19) HOOGE Sophie (13) HATCHUEL Armand (13) TERNAY Jean-François (9) LECLERC-OLIVE Michèle (9) Bourdon Marc (9) Chen Guoting (9) BARLES Sabine (8) PIKETTY Thomas (8) LUO Feng (6) VAUTHIER Jacques (6) FLAMENT Dominique (6) Tonegawa Yoshihiro (5) Toro Tatiana (5) COURTOIS Gilles (5)
Producteur(s) CANAL UNISCIEL (156) Institut Fourier (119) Inria (109) Université de tous les savoirs (54) EHESS (42) Ecole Normale Supérieure de Lyon (40) Université Paris 1 Panthéon-Sorbonne (40) Fondation maison des sciences de l'homme (34) Institut d'Enseignement à Distance / université Paris8 (25) Science en cours (23) MINES ParisTech (13) Institut d'astrophysique de Paris (12) Les Amphis de France 5 (10) École doctorale de mathématique et informatique (9) Université Toulouse-Jean Jaurès (Toulouse II-le Mirail) (8) Centre d'Enseignement Multimédia Universitaire (C.E.M.U.) Université de Caen Normandie (8) Université Le Havre Normandie (7) CERIMES (7) Collège de France (7) Université de Bordeaux - SAM (3)
Nombre de programmes trouvés : 750
le 29/06/2016 (1h4m1s)
Feng Luo - Discrete conformal geometry of polyhedral surfaces and its convergence
Our recent joint work with D. Gu established a discrete version of the uniformization theorem for compact polyhedral surfaces. In this talk, we prove that discrete uniformizaton maps converge to conformal maps when the triangulations are sufficiently fine chosen. We will also discuss the relationship between the discrete uniformization theorem and convex polyhedral surfaces in the hyperbolic 3-space. This is a joint work with J. Sun and T. Wu.
Stéphane Saboureau - Sweep-outs, width estimates and volume
Sweep-out techniques in geometry and topology have recently received a great deal of attention, leading to major breakthroughs. In this talk, we will present several width estimates relying on min-max arguments in relation to the volume of Riemannian manifolds. Dealing with the case of surfaces first, we will focus our attention on generalisations in higher dimension and present new estimates obtained in a work in progress.
Jean-Marc Schlenker - Anti-de Sitter geometry and polyhedra inscribed in quadrics
Anti-de Sitter geometry is a Lorentzian analog of hyperbolic geometry. In the last 25 years a number of connections have emerged between 3-dimensional anti-de Sitter geometry and the geometry of hyperbolic sufaces. We will explain how the study of ideal polyhedra in anti-de Sitter space leads to an answer to a question of Steiner (1832) on the combinatorics of polyhedra that can be inscribed in a quadric. Joint work with Jeff Danciger and Sara Maloni.
Burkhard Wilking - Manifolds with almost nonnegative curvature operator
We show that n-manifolds with a lower volume bound v and upper diameter bound D whose curvature operator is bounded below by $-\varepsilon(n,v,D)$ also admit metrics with nonnegative curvature operator. The proof relies on heat kernel estimates for the Ricci flow and shows that various smoothing properties of the Ricci flow remain valid if an upper curvature bound is replaced by a lower volume bound. nonnegative curvature operator.
le 28/06/2016 (1h1m10s)
Vladimir Markovic - Harmonic quasi-isometries between negatively curved manifolds
Very recently, Markovic, Lemm-Markovic and Benoist-Hulin, established the existence of a harmonic mapping in the homotopy class of an arbitrary quasi-isometry between rank 1 symmetric spaces. I will discuss these results and the more general conjecture which states that this result holds for quasi-isometries between negatively curved manifolds and metric spaces.
le 28/06/2016 (1h37s)
Juan Souto - Counting curves on surfaces
An old theorem of Huber asserts that the number of closed geodesics of length at most L on a hyperbolic surface is asymptotic to $\frac{e^L}L$. However, things are less clear if one either fixes the type of the curve, possibly changing the notion of length, or if one counts types of curves. Here, two curves are of the same type if they differ by a mapping class. I will describe some results in these directions.
Genevieve Walsh - Boundaries of Kleinian groups
We study the problem of classifying Kleinian groups via the topology of their limit sets. In particular, we are interested in one-ended convex-cocompact Kleinian groups where each piece in the JSJ decomposition is a free group, and we describe interesting examples in this situation. In certain cases we show that the type of Kleinian group is determined by the topology of its group boundary. We conjecture that this is not the case in general. We also determine the homeomorphism types of planar boundaries that can occur. This is joint work in progress with Peter Haissinsky and Luisa Paoluzzi.
David Gabai - Maximal cusps of low volume
With Robert Haraway, Robert Meyerhoff, Nathaniel Thurston and Andrew Yarmola.We address the following question. What are all the 1-cusped hyperbolic 3-manifolds whose maximal cusps have low volume? Among other things we will outline a proof that the figure-8 knot complement and its sister are the 1-cusped manifolds with minimal maximal cusp volume.
le 28/06/2016 (1h5s)
Greg McShane - Volumes of hyperbolics manifolds and translation distances
...Schlenker and Krasnov have established a remarkable Schlaffli-type formula for the (renormalized) volume of a quasi-Fuchsian manifold. Using this, some classical results in complex analysis and Gromov-Hausdorff convergence for sequences of open...
Reto Buzano - Minimal hypersurfaces with bounded index and bounded area
We study sequences of closed minimal hypersurfaces (in closed Riemannian manifolds) that have uniformly bounded index and area. In particular, we develop a bubbling result which yields a bound on the total curvature along the sequence. As a consequence, we obtain qualitative control on the topology of minimal hypersurfaces in terms of index and area. This is joint work with Ben Sharp.