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In knot theory, a Lissajous knot is a knot defined by parametric equations of the form : where , , and are integers and the phase shifts , , and may be any real numbers.〔M.G.V. Bogle, J.E. Hearst, V.F.R. Jones, L. Stoilov, "Lissajous knots", Journal of Knot Theory and Its Ramifications, 3(2), 1994, 121–140.〕 The projection of a Lissajous knot onto any of the three coordinate planes is a Lissajous curve, and many of the properties of these knots are closely related to properties of Lissajous curves. Replacing the cosine function in the parametrization by a triangle wave transforms every Lissajous knot isotopically into a billiard curve inside a cube, the simplest case of so-called ''billiard knots''. Billiard knots can also be studied in other domains, for instance in a cylinder.〔C. Lamm, D. Obermeyer. "Billiard knots in a cylinder", Journal of Knot Theory and Its Ramifications, 8(3), 1999, 353–366.〕 == Form == Because a knot cannot be self-intersecting, the three integers must be pairwise relatively prime, and none of the quantities : may be an integer multiple of pi. Moreover, by making a substitution of the form , one may assume that any of the three phase shifts , , is equal to zero. 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Lissajous knot」の詳細全文を読む スポンサード リンク
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