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List of spirals

From Wikipedia, the free encyclopedia

This list isincomplete; you can help byadding missing items.(February 2019)

Thislist of spirals includes namedspirals that have been described mathematically.

ImageNameFirst describedEquationComment
Circler=k{\displaystyle r=k}The trivial spiral
Archimedean spiral (alsoarithmetic spiral)c. 320 BCr=a+bθ{\displaystyle r=a+b\cdot \theta }
Fermat's spiral (also parabolic spiral)1636[1]r2=a2θ{\displaystyle r^{2}=a^{2}\cdot \theta }
Euler spiral (alsoCornu spiral or polynomial spiral)1696[2]x(t)=C(t),{\displaystyle x(t)=\operatorname {C} (t),\,}y(t)=S(t){\displaystyle y(t)=\operatorname {S} (t)}UsingFresnel integrals[3]
Hyperbolic spiral (alsoreciprocal spiral)1704r=aθ{\displaystyle r={\frac {a}{\theta }}}
Lituus1722r2θ=k{\displaystyle r^{2}\cdot \theta =k}
Logarithmic spiral (also known asequiangular spiral)1638[4]r=aebθ{\displaystyle r=a\cdot e^{b\cdot \theta }}Approximations of this are found in nature
Fibonacci spiralCircular arcs connecting the opposite corners of squares in the Fibonacci tilingApproximation of the golden spiral
Golden spiralr=φ2θπ{\displaystyle r=\varphi ^{\frac {2\cdot \theta }{\pi }}\,}Special case of the logarithmic spiral
Spiral of Theodorus (also known asPythagorean spiral)c. 500 BCContiguous right triangles composed of one leg with unit length and the other leg being the hypotenuse of the prior triangleApproximates the Archimedean spiral
Involute1673x(t)=r(cos(t+a)+tsin(t+a)),{\displaystyle x(t)=r(\cos(t+a)+t\sin(t+a)),}

y(t)=r(sin(t+a)tcos(t+a)){\displaystyle y(t)=r(\sin(t+a)-t\cos(t+a))}

Involutes of a circle appear like Archimedean spirals
Helixr(t)=1,{\displaystyle r(t)=1,\,}θ(t)=t,{\displaystyle \theta (t)=t,\,}z(t)=t{\displaystyle z(t)=t}A three-dimensional spiral
Rhumb line (also loxodrome)Type of spiral drawn on a sphere
Cotes's spiral17221r={Acosh(kθ+ε)Aexp(kθ+ε)Asinh(kθ+ε)A(kθ+ε)Acos(kθ+ε){\displaystyle {\frac {1}{r}}={\begin{cases}A\cosh(k\theta +\varepsilon )\\A\exp(k\theta +\varepsilon )\\A\sinh(k\theta +\varepsilon )\\A(k\theta +\varepsilon )\\A\cos(k\theta +\varepsilon )\\\end{cases}}}Solution to the two-body problem for an inverse-cube central force
Poinsot's spiralsr=acsch(nθ),{\displaystyle r=a\cdot \operatorname {csch} (n\cdot \theta ),\,}
r=asech(nθ){\displaystyle r=a\cdot \operatorname {sech} (n\cdot \theta )}
Nielsen's spiral1993[5]x(t)=ci(t),{\displaystyle x(t)=\operatorname {ci} (t),\,}
y(t)=si(t){\displaystyle y(t)=\operatorname {si} (t)}
A variation of Euler spiral, usingsine integral and cosine integrals
Polygonal spiralSpecial case approximation of arithmetic or logarithmic spiral
Fraser's Spiral1908Optical illusion based on spirals
Conchospiralr=μta,{\displaystyle r=\mu ^{t}\cdot a,\,}θ=t,{\displaystyle \theta =t,\,}z=μtc{\displaystyle z=\mu ^{t}\cdot c}A three-dimensional spiral on the surface of a cone.
Calkin–Wilf spiral
Ulam spiral (also prime spiral)1963
Sacks spiral1994Variant of Ulam spiral and Archimedean spiral.
Seiffert's spiral2000[6]r=sn(s,k),{\displaystyle r=\operatorname {sn} (s,k),\,}θ=ks{\displaystyle \theta =k\cdot s}z=cn(s,k){\displaystyle z=\operatorname {cn} (s,k)}Spiral curve on the surface of a sphere using theJacobi elliptic functions[7]
Tractrix spiral1704[8]{r=Acos(t)θ=tan(t)t{\displaystyle {\begin{cases}r=A\cos(t)\\\theta =\tan(t)-t\end{cases}}}
Pappus spiral1779{r=aθψ=k{\displaystyle {\begin{cases}r=a\theta \\\psi =k\end{cases}}}3D conical spiral studied byPappus andPascal[9]
Doppler spiralx=a(tcos(t)+kt),{\displaystyle x=a\cdot (t\cdot \cos(t)+k\cdot t),\,}y=atsin(t){\displaystyle y=a\cdot t\cdot \sin(t)}2D projection of Pappus spiral[10]
Atzema spiralx=sin(t)t2cos(t)tsin(t),{\displaystyle x={\frac {\sin(t)}{t}}-2\cdot \cos(t)-t\cdot \sin(t),\,}y=cos(t)t2sin(t)+tcos(t){\displaystyle y=-{\frac {\cos(t)}{t}}-2\cdot \sin(t)+t\cdot \cos(t)}The curve that has acatacaustic forming a circle. Approximates the Archimedean spiral.[11]
Atomic spiral2002r=θθa{\displaystyle r={\frac {\theta }{\theta -a}}}This spiral has twoasymptotes; one is the circle of radius 1 and the other is the lineθ=a{\displaystyle \theta =a}[12]
Galactic spiral2019{dx=Ryx2+y2dθdy=R[ρ(θ)xx2+y2]dθ{x=dxy=dy+R{\displaystyle {\begin{cases}dx=R\cdot {\frac {y}{\sqrt {x^{2}+y^{2}}}}d\theta \\dy=R\cdot \left[\rho (\theta )-{\frac {x}{\sqrt {x^{2}+y^{2}}}}\right]d\theta \end{cases}}{\begin{cases}x=\sum dx\\\\\\y=\sum dy+R\end{cases}}}The differential spiral equations were developed to simulate the spiral arms of disc galaxies, have 4 solutions with three different cases:ρ<1,ρ=1,ρ>1{\displaystyle \rho <1,\rho =1,\rho >1}, the spiral patterns are decided by the behavior of the parameterρ{\displaystyle \rho }. Forρ<1{\displaystyle \rho <1}, spiral-ring pattern;ρ=1,{\displaystyle \rho =1,} regular spiral;ρ>1,{\displaystyle \rho >1,} loose spiral. R is the distance of spiral starting point (0, R) to the center. The calculated x and y have to be rotated backward by (θ{\displaystyle -\theta }) for plotting.[13][predatory publisher]

See also

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References

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  1. ^"Fermat spiral - Encyclopedia of Mathematics".www.encyclopediaofmath.org. Retrieved18 February 2019.
  2. ^Weisstein, Eric W."Cornu Spiral".mathworld.wolfram.com. Retrieved2023-11-22.
  3. ^Weisstein, Eric W."Fresnel Integrals".mathworld.wolfram.com. Retrieved2023-01-31.
  4. ^Weisstein, Eric W."Logarithmic Spiral".mathworld.wolfram.com. Wolfram Research, Inc. Retrieved18 February 2019.
  5. ^Weisstein, Eric W."Nielsen's Spiral".mathworld.wolfram.com. Wolfram Research, Inc. Retrieved18 February 2019.
  6. ^Weisstein, Eric W."Seiffert's Spherical Spiral".mathworld.wolfram.com. Retrieved2023-01-31.
  7. ^Weisstein, Eric W."Seiffert's Spherical Spiral".mathworld.wolfram.com. Retrieved2023-01-31.
  8. ^"Tractrix spiral".www.mathcurve.com. Retrieved2019-02-23.
  9. ^"Conical spiral of Pappus".www.mathcurve.com. Retrieved28 February 2019.
  10. ^"Doppler spiral".www.mathcurve.com. Retrieved28 February 2019.
  11. ^"Atzema spiral".www.2dcurves.com. Retrieved11 March 2019.
  12. ^"atom-spiral".www.2dcurves.com. Retrieved11 March 2019.
  13. ^Pan, Hongjun."New spiral"(PDF).www.arpgweb.com. Retrieved5 March 2021.
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