Department of Computer Science | Institute of Theoretical Computer Science | CADMO

Theory of Combinatorial Algorithms

Prof. Emo Welzl and Prof. Bernd Gärtner

Mittagsseminar (in cooperation with A. Steger, D. Steurer and B. Sudakov)

Mittagsseminar Talk Information

Date and Time: Thursday, October 03, 2019, 12:15 pm

Duration: 30 minutes

Location: OAT S15/S16/S17

Speaker: Stefan Glock

High-girth Steiner triple systems and a Turán problem of Brown, Erdős and Sós

A Steiner triple system of order n is a set of triples in an n-set such that every pair is covered by exactly one triple. Kirkman characterised in 1847 for which n these exist. Erdős conjectured in 1973 that for fixed g and any sufficiently large admissible order n, there exists a Steiner triple system of order n with girth at least g, meaning that there are no j points which span at least j-2 triples for any 3 < j < g. We prove this conjecture asymptotically by analysing a random process. In this talk, we will discuss this result and also briefly discuss connections to a Turán problem of Brown, Erdős and Sós. partly joined with Daniela Kühn, Allan Lo and Deryk Osthus

Upcoming talks     |     All previous talks     |     Talks by speaker     |     Upcoming talks in iCal format (beta version!)

Previous talks by year:   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