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TZID:Europe/Vienna
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DTSTART:20190331T030000
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DTSTART:20191027T020000
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DTSTAMP:20260406T041117Z
UID:5ba209fb35c99313190053@ist.ac.at
DTSTART:20190509T133000
DTEND:20190509T153000
DESCRIPTION:Speaker: Lilla Tóthmérész\nhosted by Tamas Hausel\nAbstract:
  I will talk about the sandpile group of finite graphs and directed graphs
 . I will state the Riemann-Roch theorem for graphs (due to Baker-Norine)\,
  say what can be known about the case of directed graphs\, and how these t
 hings are connected to feedback arc sets. (This part is joint work with Bl
 int Hujter.)I will also talk about a very nice connection between sandpile
  groups of ribbon graphs and planarity: By Chan-Church-Grochow and Baker-W
 ang\, certain actions of the sandpile group of a ribbon graph on the spann
 ing trees are canonical if and only if the ribbon structure is planar. Wit
 h Tams Klmn and Seunghun Lee we gave a canonical definition for this actio
 n in the planar case.
LOCATION:Big Seminar room Ground floor / Office Bldg West (I21.EG.101)\, IS
 TA
ORGANIZER:cpetz@ist.ac.at
SUMMARY:Lilla Tóthmérész: Sandpile group of graphs and digraphs
URL:https://talks-calendar.ista.ac.at/events/1863
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