Julius Plücker

Julius Plücker (June 16, 1801 - May 22, 1866) was a German mathematician and physicist. He made fundamental contributions to the field of analytical geometry and was a pioneer in the investigations of cathode rays that led eventually to the discovery of the electron. He also vastly extended the study of Lamé curves.

In projective geometry, Plücker co-ordinates refer to a set of homogeneous co-ordinates introduced initially to embed the set of lines in three dimensions as a quadric in five dimensions. The construction uses 2x2 minor determinants, or equivalently the second exterior power of the underlying vector space of dimension 4. Their study was called line geometry in the nineteenth century. It is now part of the theory of Grassmannians, to which these co-ordinates apply in generality (k-dimensional subspaces of n-dimensional space).