Questions tagged [projective-geometry]
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8 questions
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Which people are considered to be the founders of Projective Geometry?
What were the fundamental principles and ideas of projective geometry that made people consider it groundbreaking and separates it from the rest of the geometry? I would love to learn about a good ...
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What is Laguerre's definition of the angle via the cross ratio?
I recently read an article which said Cayley showed that affine geometry could be developed from projective geometry after he learnt of Laguerre's definition of the angle using the cross ratio. This ...
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What motivated the development of the theory of perspective during the Renaissance? [closed]
It is said that the theory of perspective in art was greatly developed during the Renaissance because of the search for reality at this time: more realistic representations.
My question is what ...
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Who wrote "projective geometry" for the first time?
I guess Desargues did not use that term. Anyone could help me know where did it appear for the first time? Thanks
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What theorem of Sophus Lie on the number of geometries is H. Poincaré referring to?
In this quotation from Henri Poincaré's essay "Non-Euclidean Geometry" published in Nature in 1892 (No. 1165, Vol 45, p. 406), he refers to a theorem of Sophus Lie. Does anyone know a source for this ...
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What was the old system of using right circular cones to solve problems about circles in the plane?
[I asked this originally at the Math Stack Exchange, and they suggested I also ask about it here.]
I heard about this from a college professor but haven't ever been able to find any other mention of ...
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Did Einstein get inspired by projective geometry?
I read somewhere that projective geometry was an inspiration to Einstein to build the theory of relativity. However, the keyword "projective geometry" isn't mentioned in history of general relativity ...
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Where was the word "pencil" first used in (projective) geometry and what is the reason behind this curious name?
The title is pretty self-explanatory: A pencil in projective (or algebraic) geometry is the family of all lines through a point. The above-linked website tells me that Cremona, on page x of Elements ...