Configuration (geometry) - Duality of Configurations

Duality of Configurations

The projective dual to a configuration (pγ lπ) is a configuration (lπ pγ) in which the roles of "point" and "line" are exchanged. Thus, types of configurations come in dual pairs, except when taking the dual results in an isomorphic configuration. Such configurations are self-dual and in such cases p = l.

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