M. Bjorklund gave a talk in Orsay on the following problem in additive combinatorics: Given , show that is “large” unless they have a “special structure”. The size of sets is defined here in terms of their upper Banach density: where ranges over the integer sequences such that . The special structure is the following [...]
Posts Tagged ‘abstract ergodic theory’
Ergodic theory of sumsets
Posted in Dynamics, talks, tagged abstract ergodic theory, combinatorics, Dynamics on October 2, 2009 | Leave a Comment »
Bratelli diagrams, Vershik maps and Invariant measures
Posted in should have known, tagged abstract ergodic theory, Dynamics, symbolic dynamics on April 3, 2009 | 1 Comment »
DEFINITION. A Bratteli diagram is a directed graph with a distinguished vertex such that (i) any vertex can be joined from by at least one path; (ii) such paths have all the same length called the level of ; (iii) there is a finite, non-zero number of arrows leaving each vertex. Remark. Property (ii) is [...]
