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UID:20260415T075913EDT-24227i9Xu1@132.216.98.100
DTSTAMP:20260415T115913Z
DESCRIPTION:Title: A story about pointwise ergodic theorems\n\nAbstract:Poi
 ntwise ergodic theorems provide a bridge between the global behaviour of t
 he dynamical system and the local combinatorial statistics of the system a
 t a point. Such theorem have been proven in different contexts\, but typic
 ally for actions of semigroups on a probability space. Dating back to Birk
 hoff (1931)\, the first known pointwise ergodic theorem states that for a 
 measure-preserving ergodic transformation T on a probability space\, the m
 ean of a function (its global average) can be approximated by taking local
  averages of the function at a point x over finite sets in the forward-orb
 it of x\, namely {x\, Tx\, ...\, T^n x}. Almost a century later\, we revis
 it Birkhoff's theorem and turn it backwards\, showing that the averages al
 ong trees of possible pasts also approximate the global average. This back
 ward theorem for a single transformation surprisingly has applications to 
 actions of free groups\, which we will also discuss. This is joint work wi
 th Jenna Zomback.\n\n \n\nColloquium Colloque des sciences mathématiques d
 u Québec\n	Salle/Room 5340\, Pav. André Aisenstadt\, Pour obtenir les accès
  Zoom veuillez vous inscrire aux listes de votre choix / To get your Zoom 
 access\, please subscribe to the lists of your choice: https://forms.gle/a
 xqFGSkRkbkdFtE68\n\nhttp://crm.umontreal.ca/colloque-sciences-mathematique
 s-quebec/index.htm...\n
DTSTART:20220923T193000Z
DTEND:20220923T203000Z
SUMMARY:Anush Tserunyan\, Mcgill
URL:https://www.mcgill.ca/mathstat/channels/event/anush-tserunyan-mcgill-34
 1780
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