In projective geometry, the harmonic conjugate point of a point on the real projective line with respect to two other points is defined by the following...
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include "harmonic" include: Projective harmonic conjugate Cross-ratio Harmonic analysis Harmonic conjugate Harmonic form Harmonic function Harmonic mean Harmonic...
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parallelogram with d at the fourth vertex. In projective geometry, the process of finding a projective harmonic conjugate is a ternary operation on three points...
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throws (German: Wurftheorie). It is based on projective range and the relation of projective harmonic conjugates. Through operations of addition of points...
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Complete quadrangle (category Projective geometry)
at projective harmonic conjugate positions. The four points on the line deriving from the sides and diagonals of the quadrangle are called a harmonic range...
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Cross-ratio (redirect from Projective invariant)
construction of the projective harmonic conjugate, which he called a throw (German: Wurf): given three points on a line, the harmonic conjugate is a fourth point...
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Under the projective transformations, the incidence structure and the relation of projective harmonic conjugates are preserved. A projective range is the...
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the construction of the projective harmonic conjugate relation between points is part of the structure of the real projective line. For instance, given...
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affine definition of the midpoint M of a segment AB is the projective harmonic conjugate of the point at infinity, P, of the line AB. That is, the point...
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mathematics, the projective line over a ring is an extension of the concept of projective line over a field. Given a ring A (with 1), the projective line P1(A)...
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duality and beyond that to duality in any finite-dimensional projective geometry. A projective plane C may be defined axiomatically as an incidence structure...
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relation of projective harmonic conjugates. Indeed, three points on a projective line determine a fourth by this relation. Application of a projectivity to this...
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contribution to Feuerbach's theorem. He also made discoveries about projective harmonic conjugates; relating these to the poles and polar lines associated with...
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belonging to arguments θ, θ + π, θ + 2π, θ + 3π the point C is the projective harmonic conjugate of B with respect to A, D, i.e. the cross ratio (A,D;B,C) has...
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In geometry, a real projective line is a projective line over the real numbers. It is an extension of the usual concept of a line that has been historically...
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Conic section (section In the real projective plane)
is the projective harmonic conjugate of the point of intersection of AB and the absolute line, with respect to A and B. A conic in a projective plane that...
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pairs M 1 , M 2 ; E , I {\displaystyle M_{1},M_{2};E,I} are projective harmonic conjugate: Their cross ratio is ( M 1 , M 2 ; E , I ) = − 1 {\displaystyle...
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Poncelet–Steiner theorem (section Projective geometry, as it relates to the Poncelet-Steiner Theorem)
prescribed circle center. This construction is a special case of the projective harmonic conjugate construction, which is not demonstrated in this article. If...
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Hodge theory (redirect from Harmonic form)
complex projective manifold, meaning that X is a closed complex submanifold of some complex projective space CPN. By Chow's theorem, complex projective manifolds...
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Unit hyperbola (redirect from Quasi-harmonic motion)
interpreted in the projective plane using homogeneous coordinates. Then the asymptotes are lines that are tangent to the projective curve at a point at...
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Pole and polar (category Projective geometry)
line were advanced in projective geometry. For instance, the polar line can be viewed as the set of projective harmonic conjugates of a given point, the...
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"Joachimsthal's Notations". See "Conics and Joachimthal's equation" in Projective harmonic conjugate This article incorporates text from a publication now in the...
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Point-pair separation (category Projective geometry)
each other. Given any pair of points on a projective line, they separate a third point from its harmonic conjugate. A pair of lines in a pencil separates...
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corresponds to the process of inversion in projective geometry and taking the projective harmonic conjugate, which can be defined in terms of the cross...
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use of a third parallel midway between the others that is the projective harmonic conjugate of a line at infinity. In a triangle ABC the feet of the altitudes...
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Centre (geometry) (section Projective conics)
concept of centre in projective geometry uses this relation. The following assertions are from G. B. Halsted. The harmonic conjugate of a point at infinity...
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Möbius transformation (category Projective geometry)
transformations are the projective transformations of the complex projective line. They form a group called the Möbius group, which is the projective linear group...
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axioms for projective n-space, among other things, he considered the consequences of having a fourth harmonic point be equal to its conjugate. This leads...
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Pappus manipulated the complete quadrangle, used the relation of projective harmonic conjugates, and displayed an awareness of cross-ratios of points and lines...
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(Baker 1922b, vol 2, p. 26) 4. For harmonic conjugate see harmonic. connex A correspondence between a projective space and its dual. consecutive Infinitesimally...
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