• Séminaire

Séminaire du Cirget: «Circle squaring and actions of Z^n»

Conférencier: Marcin Sabok, McGill University

Résumé/Abstract: In 1930's Tarski asked if it is possible to divide the unit square into finitely many pieces, rearrange them by translations and get a disc of area 1. It turns out that this is possible and proved by Laczkovich in the 1990's. His decomposition, however, used nonmeasurable pieces and seemed paradoxical. Recently, Grabowski, Mathe and Pikhurko and Marks and Unger showed that such decompositions can be obtained using nice measurable pieces. I will discuss an abstract result in measurable group theory of ergodic actions of the groups Z^n that lies behind this recent result. This is joint work with T. Ciesla. 

clockCreated with Sketch.Date / heure

vendredi 7 décembre 2018
10 h à 11 h

pinCreated with Sketch.Lieu

UQAM - Pavillon Président-Kennedy (PK)
PK-5115
201, avenue du Président-Kennedy
Montréal (QC) H2X 2J6

personCreated with Sketch.Renseignements

Mots-clés

  • Recherche
  • Mathématiques

Groupes

  • Département de mathématiques
  • Centre interuniversitaire de recherches en géométrie et topologie (CIRGET)