Department of Computer Science | Institute of Theoretical Computer Science | CADMO
Prof. Emo Welzl and Prof. Bernd Gärtner
Mittagsseminar Talk Information |
Date and Time: Tuesday, November 01, 2005, 12:15 pm
Duration: This information is not available in the database
Location: This information is not available in the database
Speaker: Alexander Engström
A subset of the vertex set of a graph is independent if its induced subgraph has no edges.
Given a graph, a game is played between an angel and the devil. The goal of the angel is to determine if a set of vertices is independent or not, without knowing exactly which vertices are in the set. When they start the angel knows nothing, but she can ask the devil if vertices are in the set or not. The devil wins if the angel asks about the complete vertex set.
Strategies for the angel, and how much she must cheat to win, give information about a topological space constructed from the independent sets, called the independence complex. Using this game we get easier proofs and generalize recent results by Ehrenborg and Hetyei on independence complexes of trees, and work by Kalai and Meshulam on independence complexes of graphs with degree restrictions. Also, this game gives a combinatorial proof of a theorem on chessboard complexes by Björner and Lovász.
Upcoming talks | All previous talks | Talks by speaker | Upcoming talks in iCal format (beta version!)
Previous talks by year: 2025 2024 2023 2022 2021 2020 2019 2018 2017 2016 2015 2014 2013 2012 2011 2010 2009 2008 2007 2006 2005 2004 2003 2002 2001 2000 1999 1998 1997 1996
Information for students and suggested topics for student talks
Automatic MiSe System Software Version 1.4803M | admin login