Difference between revisions of "Darboux trihedron"
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+ | $#C+1 = 4 : ~/encyclopedia/old_files/data/D030/D.0300200 Darboux trihedron | ||
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+ | A trihedron associated with a point on a surface and defined by a triple of vectors, given by the normal unit vector $ \mathbf n $ | ||
+ | to the surface and two mutually orthogonal principal unit tangent vectors $ \mathbf r _ {1} $ | ||
+ | and $ \mathbf r _ {2} $ | ||
+ | to the surface such that | ||
+ | |||
+ | $$ | ||
+ | \mathbf n = \mathbf r _ {1} \times \mathbf r _ {2} . | ||
+ | $$ | ||
The properties of the surface can be described in terms of displacement of the Darboux trihedron when its base point describes the surface. A systematic use of the Darboux trihedron in the study of surfaces led G. Darboux [[#References|[1]]] to the [[Moving-frame method|moving-frame method]]. | The properties of the surface can be described in terms of displacement of the Darboux trihedron when its base point describes the surface. A systematic use of the Darboux trihedron in the study of surfaces led G. Darboux [[#References|[1]]] to the [[Moving-frame method|moving-frame method]]. | ||
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====References==== | ====References==== | ||
<table><TR><TD valign="top">[1]</TD> <TD valign="top"> G. Darboux, "Leçons sur la théorie générale des surfaces et ses applications géométriques du calcul infinitésimal" , '''1''' , Gauthier-Villars (1887)</TD></TR></table> | <table><TR><TD valign="top">[1]</TD> <TD valign="top"> G. Darboux, "Leçons sur la théorie générale des surfaces et ses applications géométriques du calcul infinitésimal" , '''1''' , Gauthier-Villars (1887)</TD></TR></table> | ||
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====Comments==== | ====Comments==== |
Latest revision as of 17:32, 5 June 2020
A trihedron associated with a point on a surface and defined by a triple of vectors, given by the normal unit vector $ \mathbf n $
to the surface and two mutually orthogonal principal unit tangent vectors $ \mathbf r _ {1} $
and $ \mathbf r _ {2} $
to the surface such that
$$ \mathbf n = \mathbf r _ {1} \times \mathbf r _ {2} . $$
The properties of the surface can be described in terms of displacement of the Darboux trihedron when its base point describes the surface. A systematic use of the Darboux trihedron in the study of surfaces led G. Darboux [1] to the moving-frame method.
References
[1] | G. Darboux, "Leçons sur la théorie générale des surfaces et ses applications géométriques du calcul infinitésimal" , 1 , Gauthier-Villars (1887) |
Comments
A Darboux trihedron is also called a Darboux frame. It is also introduced in affine differential geometry, cf. [a1].
References
[a1] | H.W. Guggenheimer, "Differential geometry" , McGraw-Hill (1963) |
Darboux trihedron. Encyclopedia of Mathematics. URL: http://encyclopediaofmath.org/index.php?title=Darboux_trihedron&oldid=14346