Word metric

In group theory, a word metric on a group G is a way to measure distance between any two elements of G . As the name suggests, the word metric is a metric on G , assigning to any two elements g , h of G a distance d(g,h) that measures how efficiently their difference g^{-1} h can be expressed as a word whose letters come from a generating set for the group. The word metric on G is very closely related to the Cayley graph of G: the word metric measures the length of the shortest path in the Cayley graph between two elements of G.

Related Topics:
Group theory - Group - Metric - Word - Generating set - Cayley graph

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A generating set for G must first be chosen before a word metric on G is specified. Different choices of a generating set will typically yield different word metrics. While this seems at first to be a weakness in the concept of the word metric, it can be exploited to prove theorems about geometric properties of groups, as is done in Geometric group theory.

Related Topics:
Generating set - Geometric group theory

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