projective geometry

American  

noun

1. the geometric study of projective properties.

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projective geometry British  

noun

1. the branch of geometry concerned with the properties of solids that are invariant under projection and section

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Etymology

Origin of projective geometry

First recorded in 1880–85

Example Sentences

The principal subjects studied were: "The relation of generalized projective geometry to classical projective geometry, projective relativity, the theory of spinors,* conformal geometry and its relation to unitary field theory."

From Time Magazine Archive

This was the beginning of the discipline of projective geometry, where mathematicians look at the shadows and projections of geometric figures to uncover hidden truths even more powerful than the equivalence of parabolas and ellipses.

From "Zero: The Biography of a Dangerous Idea" by Charles Seife

However, Poncelet had no idea that projective geometry would reveal the mysterious nature of zero, because the second important advance, the complex plane, was still needed.

From "Zero: The Biography of a Dangerous Idea" by Charles Seife

Gérard Desargues, a seventeenth-century French architect, was one of the early pioneers of projective geometry.

From "Zero: The Biography of a Dangerous Idea" by Charles Seife

Riemann merged projective geometry with the complex numbers, and all of a sudden lines became circles, circles became lines, and zero and infinity became the poles on a globe full of numbers.

From "Zero: The Biography of a Dangerous Idea" by Charles Seife