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Ci-dessous, les différences entre deux révisions de la page.

--- fables [2022/06/20 15:46] – g.m
+++ fables [2023/02/12 13:07] – kalinin0
@@ Ligne 1: / Ligne 1: @@
 ====== Séminaire "Fables Géométriques". ======
+----
+  Monday, February 27, 2023
+  room 6-13
+**15h00 Evgeni Abakoumov (Paris/Eiffel U)**
+**Chui's conjecture аnd rational approximation**
+Abstract:  C. K. Chui conjectured in 1971 that the average gravitaional field strength in the unit disk due to unit point masses on its boundary was the smallest when these point masses were equidistributed on the circle. We will present an elementary solution to some weighted versions of this problem, and discuss related questions concerning approximation of holomorphic functions by simple partial fractions. This is joint work with A. Borichev and K. Fedorovskiy.
+** 16h00  Ferit Ozturk (Istanbul/Bosphorus U and Budapest/Renyi Inst)**
+**Every real 3-manifold admits a real contact structure**
+Abstract: We survey our results regarding real contact 3-manifolds and present our result in the title.
+A real 3-manifold is a smooth 3-manifold together with an orientation preserving smooth involution, called a real structure.
+A real contact 3-manifold is a real 3-manifold with a contact distribution that is antisymmetric with respect to the real structure.
+The standard examples of real contact 3-manifolds are link manifolds of isolated, real analytic surface singularities.
+We show that every real contact 3-manifold can be obtained via contact surgery along invariant knots starting from the standard real contact 3-sphere.
+As a corollary we show that any oriented overtwisted contact structure on an integer homology real 3-sphere can be isotoped to be real.
+----
+  Monday, February 6, 2023
+:00, room 6-13
+**Sergey Finashin (Ankara)**
+**“Affine Real Cubic Surfaces”**
+Abstract: (A joint work with V.Kharlamov) We prove that the space of
+affine, transversal at infinity, non-singular real cubic surfaces has 15 connected components. We give a topological criterion to distinguish them and show also how these 15 components are adjacent to each other via wall-crossing.
 ----
@@ Ligne 13: / Ligne 47: @@
 Abstract: The highly non-trivial stable homotopy groups of the Waldhausen’s
 h-cobordism space inject into the homotopy groups of spaces of appropriate Legendrian submanifolds. For instance,  there is  a  homotopically non-trivial 2-parametric family of Legendrian unknots in ${\mathbb R}^{2n+1}$ for a sufficiently large $n$. This is a joint work with Thomas Kragh.
-----
-  Monday, Dec, 20th, 16h15 - 18h15
-**On the asymptotics of Arakelov invariants**
-We will discuss the asymptotics of invariants of Riemann
-surfaces motivated by Arakelov theory. These invariants play a
-fundamental role in bounds for the number of geometric torsion points on
-curves. We will show that their asymptotic behaviour in families of
-degenerating Riemann surfaces is controlled by their tropical counterparts.
 ----
   Fri 17.12.2021, 13h30, room 6-13