# Noon lecture

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On 11.06.2014 at 12:20 in S6, there is the following noon lecture:

# Points and lines in metric spaces

## Václav Chvátal

## Concordia University, Montreal; Canada Research Chair in Discrete Mathematics

## Abstract

The notion of lines in a Euclidean spaces can be generalized to a definition of lines in metric spaces in at least two distinct ways. The classical Sylvester-Gallai theorem of Euclidean geometry has been generalized to all metric spaces with one of the two definitions of lines; its corollary, customarily and not quite correctly referred to as a De Bruijn-Erdos theorem, has been conjectured to allow a generalization to all metric spaces with the other definition of lines.

Webmaster: kamweb.mff.cuni.cz Modified: 19. 10. 2010