 ##  [Projective Geometry](/projective-geometry) 

  ##  [Projective Geometry](https://puremath.quantumdictionary.io/projective-geometry-0) 

  
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- Mathematics &amp; Logic -

**Pure Mathematics Dictionary**

 
Definition

The study of incidence relations and invariants under projective transformations, extending affine geometry by adding points at infinity so that parallel lines meet, centering on cross-ratio, perspectivity, and duality between points and lines while ignoring metrical measures.