X-Nico

unusual facts about projective geometry



Erlangen program

Klein proposed an idea that all these new geometries are just special cases of the projective geometry, as already developed by Poncelet, Möbius, Cayley and others.

John Wesley Young

John Wesley Young (November 17, 1879, Columbus, Ohio, to February 17, 1932, Hanover, New Hampshire) was an American mathematician who, with Oswald Veblen, introduced the axioms of projective geometry, coauthored a 2-volume work on them, and proved the Veblen–Young theorem.

Julius Plücker

In projective geometry, Plücker coordinates 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.

Semifield

In projective geometry and finite geometry (MSC 51A, 51E, 12K10), a semifield is the analogue of a division algebra, but defined over the integers Z rather than over a field.


see also

Corrado Segre

He began to instruct in projective geometry, as stand-in for Giuseppe Bruno, from 1885 to 1888.

Cross-ratio

Dirk Struik (1953) Lectures on Analytic and Projective Geometry, page 7, Addison-Wesley.

Finite geometry

The first finite projective geometry was developed by the Italian mathematician Gino Fano.