"Most programs for computing Julia sets work well when the underlying dynamics is hyperbolic but experience an exponential slowdown in the parabolic case." ( Mark Braverman )^{[1]}
In other words it means that one can need days for making a good picture of parabolic Julia set with standard / naive algorithms.
There are 2 problems here :
 slow (= lazy) local dynamics ( in the neighbourhood of a parabolic fixed point )
 some parts are very thin ( hard to find using standard plane scanning)
Contents
PlanesEdit
Dynamic planeEdit
Dynamic plane = complex zplane :
 Julia set is a common boundary :
 Fatou set
 exterior of Julia set = basin of attraction to infinity :
 interior of Julia set = basin of attraction of finite, parabolic fixed point p :
 immediate basin = sum of componets which have parabolic fixed point p on it's boundary ; the immediate parabolic basin of p is the union of periodic connected components of the parabolic basin.
See also :
 Filled Julia set^{[3]}
Key wordsEdit
 parabolic chessboard or checkerboard
 parabolic implosion
 Fatou coordinate
 Gevrey symptotic expansions
 the ÉcalleVoronin invariants of (7.1) at the origin which have Gevrey 1/2 asymptotic expansions^{[4]}
 germ^{[5]}^{[6]} ^{[7]}
 germ of the function : Taylor expansion of the function
 multiplicity^{[8]}
 JuliaLavaurs sets
 The LeauFatou flower theorem^{[9]} : repelling or attracting flower. Flower consist of petals
 Parabolic Linearization theorem
 The horn map
 Blaschke product
 Inou and Shishikura's near parabolic renormalization
 complex polynomial vector field ^{[10]}
 numbers
 "a positive integer ν, the parabolic degeneracy with the following property: there are νq attracting petals and νq repelling petals, which alternate cyclically around the fixed point." ^{[11]}
 combinatorial rotation number
 a Poincaré linearizer of function f at parabolic fixed point^{[12]}
Ecalle cilinderEdit
Ecalle cylinders^{[13]} or EcalleVoronin cylinders ( by Jean Ecalle^{[14]} ^{[15]})
"... the quotient of a petal P under the equivalence relation identifying z and f (z) if both z and f (z) belong to P. This quotient manifold is called the Ecalle cilinder, and it is conformally isomorphic to the infinite cylinder C/Z"^{[16]}
eggbeater dynamicsEdit
Physical model : the behaviour of cake when one uses eggbeater.
The mathematical model : a 2D vector field with 2 centers ( secondorder degenerate points ) ^{[17]}^{[18]}
The field is spinning about the centers, but does not appear to be diverging.
parabolic germEdit
Germ : ^{[19]}^{[20]}^{[21]}
 z+z^2
 z+z^3
 z+z^{k+1}
 z+a_{k+1}z^{k+1}
 z+a_{k+1}z^{k+1}
 "a germ with is holomorphically conjugated to its linear part " ( Sylvain Bonnot )^{[22]}
germ of vector field
The horn mapEdit
" the horn map h = Φ ◦ Ψ, where Φ is a shorthand for Φattr and Ψ for Ψrep (extended Fatou coordinate and parameterizations)." ^{[23]}
PetalEdit
"The petals ... are interesting not only because they give a rather good intuitive idea of the dynamics that arise near a parabolic point, but also because that the dynamic of f0 on a petal can be linearized, i.e., it is conjugated to the shift map T of C defined by T(w) := w + 1." ( Laurea Triennale ^{[24]} )
There is no unified definition of petals.
Petal of a flower can be :
 attracting / repelling
 small/alfa/big/ ( small attracting petals do not ovelap with repelling petals, but big do)
Each petal is invariant under f^period. In other words it is mapped to itself by f^period.
Attracting petal P is a :
 Each petal is invariant under . In other words it is mapped to itself by :
 domain (topological disc ) containing :
 parabolic periodic point p in its boundary ( precisely in its root , which is a coomon points of all attracting and repelling petals = center of the LeaFatou flower)
 critical point or it's n=period images on the other side ( only small ?? )
 trap which captures any orbit tending to parabolic point ^{[25]}
 set contained inside component of filledin Julia set. The attracting petals of parabolic fixed point are contained in it's basin of attraction
 " ... is maximal with respect to this property. This preferred petal P max always has one or more critical points on its boundary."^{[26]}
 "an attracting petal is the interior of an analytic curve which lies entirely in the Fatou set, has the right tangency property at the fixed point, and is mapped into its interior by the correct power of the map" Scott Sutherland
Petals are symmetric with respect to the d1 directions :
where :
 d is (to do)
 l is from 0 to d2
Petals can have different size.
If then Julia set should approach parabolic periodic point in n directions, between n petals. ^{[27]}
" Using the language of holomorphic dynamics, people would say that you are studying the dynamics of a polynomial near the parabolic fixed point . By a simple linear change of variables, the study of any such parabolic fixed point can be reduced to the study of . Then you can apply another change . Thus you are reduced to the study of . If the real part $Re(w)$ is large enough you will obtain . This will give you what you want (when going back to the zvariable).
The domain (for large ) looks like some kind of cardioid (in your particular case) when you visualize it in the zvariable (it's poetically called an attracting petal). " Sylvain Bonnot ^{[28]}
0/1Edit
Cpp code by Wolf Jung see function parabolic from file mndlbrot.cpp ( program mandel ) ^{[29]}^{[30]}
To see effect :
 run Mandel
 (on parameter plane ) find parabolic point for angle 0, which is c=0.25. To do it use key c, in window input 0 and return.
C code :
// in function uint mndlbrot::esctime(double x, double y)
if (b == 0.0 && !drawmode && sign < 0
&& (a == 0.25  a == 0.75)) return parabolic(x, y);
// uint mndlbrot::parabolic(double x, double y)
if (Zx>=0 && Zx <= 0.5 && (Zy > 0 ? Zy : Zy)<= 0.5  Zx)
{ if (Zy>0) data[i]=200; // show petal
else data[i]=150;}
Gnuplot code :
reset
f(x,y)= x>=0 && x<=0.5 && (y > 0 ? y : y) <= 0.5  x
unset colorbox
set isosample 300, 300
set xlabel 'x'
set ylabel 'y'
set sample 300
set pm3d map
splot [2:2] [2:2] f(x,y)
1/2Edit
Cpp code by Wolf Jung see function parabolic from file mndlbrot.cpp ( program mandel ) ^{[31]} To see effect :
 run Mandel
 (on parameter plane ) find parabolic point for angle 1/2, which is c=0.75. To do it use key c, in window input 0 and return.
C code :
// in function uint mndlbrot::esctime(double x, double y)
if (b == 0.0 && !drawmode && sign < 0
&& (a == 0.25  a == 0.75)) return parabolic(x, y);
// uint mndlbrot::parabolic(double x, double y)
if (A < 0 && x >= 0.5 && x <= 0 && (y > 0 ? y : y) <= 0.3 + 0.6*x)
{ if (j & 1) return (y > 0 ? 65282u : 65290u);
else return (y > 0 ? 65281u : 65289u);
}
1/3Edit
Method by Scott Sutherland:
 choose the connected component containing the critical point
 find an analytic curve which lies entirely in the Fatou set, has the right tangency property at the fixed point, and is mapped into its interior by the correct power of the map
 the other two are just the image of this curve under the first and second iterates.
Number of petalsEdit

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For quadratic polynomials :
Multiplicity = ParentPeriod + ChildPeriod
NumberOfPetals = multiplicity  ParentPeriod
It is because in parabolic case fixed point coincidence with periodic cycle. Length of cycle ( child period) is equal to number of petals
For other polynomial maps :
f(z)  number of petals  explanation 

d1  for point z=0 has multiplicity d  
d+2  (?)for a root z=0 has multiplicity d+3  
For f(z)= z+z^(p+1) parabolic flower has :
 2p petals for p odd
 p petals for p even ^{[32]}
... ( to do )
SepalEdit
Definitions:
 A sepal is the intersection of an attracting and repelling petal.A parabolic PommerenkeLevinYoccoz inequality. by Xavier Buf and Adam L. Epstein There does not seem to be an official definition of sepal.
 "Let l be an invariant curve in the first quadrant and L1 the region enclosed by l ∪ {0}, called a sepal." ^{[33]}
FlowerEdit
Sum of all petals creates a flower with center at parabolic periodic point.^{[34]}
"... an attracting petal is a set of points in a sufficient small disk around the periodic point whose forward orbits always remain in the disk under powers of return map. " ( W P Thurston : On the geometry and dynamics of Iterated rational maps)
CauliflowerEdit
Cauliflower or broccoli :^{[35]}
 empty ( its interior is empty ) for c outside Mandelbrot set. Julia set is a totally disconnected (
 filled cauliflower for c=1/4 on boundary of the Mandelbrot set. Julia set is a Jordan curve ( quasi circle).
Pleae note that :
 size of image differs because of different zplanes.
 different algorithms are used so colours are hard to compare
Bifurcation of the CauliflowerEdit
How Julia set changes along real axis ( going from c=0 thru c=1/4 and futher ) :
Perturbation of a function by complex :
When one add epsilon > 0 ( move along real axis toward + infinity ) there is a bifurcation of parabolic fixed point :
 attracting fixed point ( epsilon<0 )
 one parabolic fixed point ( epsilon = 0 )
 one parabolic fixed point splits up into two conjugate repelling fixed points ( epsilon > 0 )
"If we slightly perturb with epsilon<0 then the parabolic fixed point splits up into two real fixed points on the real axis (one attracting, one repelling). "
See :
 demo 2 page 9 in program Mandel by Wolf Jung
parabolic implosionEdit
Video on YouTube^{[36]}
Vector fieldEdit
 2D vector field and its
singularityEdit
singularity types :
 center type : "In this case, one can find a neighborhood of the singular point where all integral curves are closed, inside one another, and contain the singular point in their interior" ^{[37]}
 noncenter type : neighborhood of singularity is made of several curvilinear sectors :^{[38]}
" A curvilinear sector is defined as the region bounded by a circle C with arbitrary small radius and two streamlines S and S! both converging towards singularity. One then considers the streamlines passing through the open sector g in order to distinguish between three possible types of curvilinear sectors."
Local dynamicsEdit
Local dynamics :
 in the exterior of Julia set
 on the Julia set
 near parabolic fixed point ( inside Julia set )
Near parabolic fixed pointEdit
Why analyze f^p not f ?
Forward orbit of f near parabolic fixed point is composite. It consist of 2 motions :
 around fixed point
 toward / away from fixed point
How to compute parabolic c valuesEdit
n  Internal angle (rotation number) t = 1/n  The root point c = parabolic parameter  Two external angles of parameter rays landing on the root point c (1/(2^n+1); 2/(2^n+1)  fixed point  external angles of dynamic rays landing on fixed point 

1  1/1  0.25  (0/1 ; 1/1)  0.5  (0/1 = 1/1) 
2  1/2  0.75  (1/3; 2/3)  0.5  (1/3; 2/3) 
3  1/3  0.64951905283833*%i0.125  (1/7; 2/7)  0.43301270189222*%i0.25  (1/7; 2/7; 3/7) 
4  1/4  0.5*%i+0.25  (1/15; 2/15)  0.5*%i  (1/15; 2/15; 4/15; 8/15) 
5  1/5  0.32858194507446*%i+0.35676274578121  (1/31; 2/31)  0.47552825814758*%i+0.15450849718747  (1/31; 2/31; 4/31; 8/31; 16/31) 
6  1/6  0.21650635094611*%i+0.375  (1/63; 2/63)  0.43301270189222*%i+0.25  (1/63; 2/63; 4/63; 8/63; 16/63; 32/63) 
7  1/7  0.14718376318856*%i+0.36737513441845  (1/127; 2/127)  0.39091574123401*%i+0.31174490092937  (1/127; 2/127, 4/127; 8/127; 16/127; 32/127, 64/127) 
8  1/8  0.10355339059327*%i+0.35355339059327  0.35355339059327*%i+0.35355339059327  
9  1/9  0.075191866590218*%i+0.33961017714276  0.32139380484327*%i+0.38302222155949  
10  1/10  0.056128497072448*%i+0.32725424859374  0.29389262614624*%i+0.40450849718747 
For internal angle n/p parabolic period p cycle consist of one zpoint with multiplicity p^{[39]} and multiplier = 1.0 . This point z is equal to fixed point
Period 1Edit
One can easily compute boundary point c
of period 1 hyperbolic component ( main cardioid) for given internal angle ( rotation number) t using this cpp code by Wolf Jung^{[40]}
t *= (2*PI); // from turns to radians
cx = 0.5*cos(t)  0.25*cos(2*t);
cy = 0.5*sin(t)  0.25*sin(2*t);
or this Maxima CAS code :
/* conformal map from circle to cardioid ( boundary of period 1 component of Mandelbrot set */ F(w):=w/2w*w/4; /* circle D={w:abs(w)=1 } where w=l(t,r) t is angle in turns ; 1 turn = 360 degree = 2*Pi radians r is a radius */ ToCircle(t,r):=r*%e^(%i*t*2*%pi); GiveC(angle,radius):= ( [w], /* point of unit circle w:l(internalAngle,internalRadius); */ w:ToCircle(angle,radius), /* point of circle */ float(rectform(F(w))) /* point on boundary of period 1 component of Mandelbrot set */ )$ compile(all)$ /*  global constants & var */ Numerator :1; DenominatorMax :10; InternalRadius:1; /*  main  */ for Denominator:1 thru DenominatorMax step 1 do ( InternalAngle: Numerator/Denominator, c: GiveC(InternalAngle,InternalRadius), display(Denominator), display(c), /* compute fixed point */ alfa:float(rectform((1sqrt(14*c))/2)), /* alfa fixed point */ display(alfa) )$
Period 2Edit
// cpp code by W Jung http://www.mndynamics.com
t *= (2*PI); // from turns to radians
cx = 0.25*cos(t)  1.0;
cy = 0.25*sin(t);
Periods 16Edit
/* batch file for Maxima CAS computing bifurcation points for period 16 Formulae for cycles in the Mandelbrot set II Stephenson, John; Ridgway, Douglas T. Physica A, Volume 190, Issue 12, p. 104116. */ kill(all); remvalue(all); start:elapsed_run_time (); /*  functions */ /* exponential for of complex number with angle in turns */ /* "exponential form prevents allroots from working", code by Robert P. Munafo */ GivePoint(Radius,t):=rectform(ev(Radius*%e^(%i*t*2*%pi), numer))$ /* gives point of unit circle for angle t in turns */ GiveCirclePoint(t):=rectform(ev(%e^(%i*t*2*%pi), numer))$ /* gives point of unit circle for angle t in turns Radius = 1 */ /* gives a list of iMax points of unit circle */ GiveCirclePoints(iMax):=block( [circle_angles,CirclePoints], CirclePoints:[], circle_angles:makelist(i/iMax,i,0,iMax), for t in circle_angles do CirclePoints:cons(GivePoint(1,t),CirclePoints), return(CirclePoints) /* multipliers */ )$ /* http://commons.wikimedia.org/wiki/File:Mandelbrot_set_Components.jpg Boundary equation b_n(c,P)=0 defines relations between hyperbolic components and unit circle for given period n , allows computation of exact coordinates of hyperbolic componenets. b_n(w,c), is boundary polynomial ( implicit function of 2 variables ). */ GiveBoundaryEq(P,n):= block( if n=1 then return(c + P^2  P), if n=2 then return( c + P  1), if n=3 then return(c^3 + 2*c^2  (P1)*c + (P1)^2), if n=4 then return( c^6 + 3*c^5 + (P+3)* c^4 + (P+3)* c^3  (P+2)*(P1)*c^2  (P1)^3), if n=5 then return(c^15 + 8*c^14 + 28*c^13 + (P + 60)*c^12 + (7*P + 94)*c^11 + (3*P^2 + 20*P + 116)*c^10 + (11*P^2 + 33*P + 114)*c^9 + (6*P^2 + 40*P + 94)*c^8 + (2*P^3  20*P^2 + 37*P + 69)*c^7 + (3*P  11)*(3*P^2  3*P  4)*c^6 + (P  1)*(3*P^3 + 20*P^2  33*P  26)*c^5 + (3*P^2 + 27*P + 14)*(P  1)^2*c^4  (6*P + 5)*(P  1)^3*c^3 + (P + 2)*(P  1)^4*c^2  c*(P  1)^5 + (P  1)^6), if n=6 then return( c^27+ 13*c^26+ 78*c^25+ (293  P)*c^24+ (792  10*P)*c^23+ (1672  41*P)*c^22+ (2892  84*P  4*P^2)*c^21+ (4219  60*P  30*P^2)*c^20+ (5313 + 155*P  80*P^2)*c^19+ (5892 + 642*P  57*P^2 + 4*P^3)*c^18+ (5843 + 1347*P + 195*P^2 + 22*P^3)*c^17+ (5258 + 2036*P + 734*P^2 + 22*P^3)*c^16+ (4346 + 2455*P + 1441*P^2  112*P^3 + 6*P^4)*c^15 + (3310 + 2522*P + 1941*P^2  441*P^3 + 20*P^4)*c^14 + (2331 + 2272*P + 1881*P^2  853*P^3  15*P^4)*c^13 + (1525 + 1842*P + 1344*P^2  1157*P^3  124*P^4  6*P^5)*c^12 + (927 + 1385*P + 570*P^2  1143*P^3  189*P^4  14*P^5)*c^11 + (536 + 923*P  126*P^2  774*P^3  186*P^4 + 11*P^5)*c^10 + (298 + 834*P + 367*P^2 + 45*P^3  4*P^4 + 4*P^5)*(1P)*c^9 + (155 + 445*P  148*P^2  109*P^3 + 103*P^4 + 2*P^5)*(1P)*c^8 + 2*(38 + 142*P  37*P^2  62*P^3 + 17*P^4)*(1P)^2*c^7 + (35 + 166*P + 18*P^2  75*P^3  4*P^4)*((1P)^3)*c^6 + (17 + 94*P + 62*P^2 + 2*P^3)*((1P)^4)*c^5 + (7 + 34*P + 8*P^2)*((1P)^5)*c^4 + (3 + 10*P + P^2)*((1P)^6)*c^3 + (1 + P)*((1P)^7)*c^2 + c*((1P)^8) + (1P)^9) )$ /* gives a list of points c on boundaries on all components for give period */ GiveBoundaryPoints(period,Circle_Points):=block( [Boundary,P,eq,roots], Boundary:[], for m in Circle_Points do (/* map from reference plane to parameter plane */ P:m/2^period, eq:GiveBoundaryEq(P,period), /* Boundary equation b_n(c,P)=0 */ roots:bfallroots(%i*eq), roots:map(rhs,roots), for root in roots do Boundary:cons(root,Boundary)), return(Boundary) )$ /* divide llist of roots to 3 sublists = 3 components */ /*  boundaries of period 3 components period:3$ Boundary3Left:[]$ Boundary3Up:[]$ Boundary3Down:[]$ Radius:1; for m in CirclePoints do ( P:m/2^period, eq:GiveBoundaryEq(P,period), roots:bfallroots(%i*eq), roots:map(rhs,roots), for root in roots do ( if realpart(root)<1 then Boundary3Left:cons(root,Boundary3Left), if (realpart(root)>1 and imagpart(root)>0.5) then Boundary3Up:cons(root,Boundary3Up), if (realpart(root)>1 and imagpart(root)<0.5) then Boundary3Down:cons(root,Boundary3Down) ) )$  */ /* gives a list of parabolic points for given : period and internal angle */ GiveParabolicPoints(period,t):=block ( [m,ParabolicPoints,P,eq,roots], m: GiveCirclePoint(t), /* root of unit circle, Radius=1, angle t=0 */ ParabolicPoints:[], /* map from reference plane to parameter plane */ P:m/2^period, eq:GiveBoundaryEq(P,period), /* Boundary equation b_n(c,P)=0 */ roots:bfallroots(%i*eq), roots:map(rhs,roots), for root in roots do ParabolicPoints:cons(float(root),ParabolicPoints), return(ParabolicPoints) )$ compile(all)$ /*  constant values */ fpprec:16; /* unit circle on a wplane */ a:GiveParabolicPoints(6,1/3); a$
How to draw parabolic Julia setEdit
All points of interior of filled Julia set tend to one periodic orbit ( or fixed point ). This point is in Julia set and is weakly attracting. ^{[41]} One can analyse only behevior near parabolic fixed point. It can be done using critical orbits.
There are two cases here : easy and hard.
If the Julia set near parabolic fixed point is like nth arm star ( not twisted) then one can simply check argument of of zn, relative to the fixed point. See for example z+z^5. This is an easy case.
In the hard case Julia set is twisted around fixed.
Estimation from exteriorEdit
Escape timeEdit
Long iteration methodEdit
Long iteration method ^{[42]}
Dynamic raysEdit
One can use periodic dynamic rays landing on parabolic fixed point to find narrow parts of exterior.
Let's check how many backward iterations needs point on periodic ray with external radius = 4 to reach distance 0.003 from parabolic fixed point :
period  Inverse iterations  time 

1  340  0m0.021s 
2  55 573  0m5.517s 
3  8 084 815  13m13.800s 
4  1 059 839 105  1724m28.990s 
One can use only argument of point z of external rays and its distance to alfa fixed point. ( see code from image) It works for periods up to 15 ( maybe more ... )
Estimation from interiorEdit
Julia set is a boundary of filledin Julia set Kc.
 find points of interior of Kc
 find boundary of interior of Kc using edge detection
If components of interior are lying very close to each other then find components using :^{[43]}
color = LastIteration % period
For parabolic components between parent and child component :^{[44]}
periodOfChild = denominator*periodOfParent color = iLastIteration % periodOfChild
where denominator is a denominator of internal angle of parent comonent of Mandelbrot set.
AngleEdit
"if the iterate zn of tends to a fixed parabolic point, then the initial seed z0 is classified according to the argument of zn−z0, the classification being provided by the flower theorem " ( Mark McClure ^{[45]})
Attraction timeEdit
Interior of filled Julia set consist of components. All comonents are preperiodic, some of them are periodic ( immediate basin of attraction).
In other words :
 one iteration moves z to another component ( and whole component to another component)
 all point of components have the same attraction time ( number of iteration needed to reach target set around attractor)
It is possible to use it to color components. Because in parabolic case attractor is weak ( weakly attracting) it needs a lot of iterations for some points to reach it.
// i = number of iteration
// iPeriodChild = period of child component of Mandelbrot set ( parabolic c value is a root point between parant and child component
/* distance from z to Alpha */
Zxt=ZxdAlfaX;
Zyt=ZydAlfaY;
d2=Zxt*Zxt +Zyt*Zyt;
// interior : check if fall into internal target set ( circle around alfa fixed point )
if (d2<dMaxDistance2Alfa2) return iColorsOfInterior[i % iPeriodChild];
Here are some example values :
iWidth = 1001 // width of image in pixels PixelWidth = 0.003996 AR = 0.003996 // Radius around attractor denominator = 1 ; Cx = 0.250000000000000; Cy = 0.000000000000000 ax = 0.500000000000000; ay = 0.000000000000000 denominator = 2 ; Cx = 0.750000000000000; Cy = 0.000000000000000 ax = 0.500000000000000; ay = 0.000000000000000 denominator = 3 ; Cx = 0.125000000000000; Cy = 0.649519052838329 ax = 0.250000000000000; ay = 0.433012701892219 denominator = 4 ; Cx = 0.250000000000000; Cy = 0.500000000000000 ax = 0.000000000000000; ay = 0.500000000000000 denominator = 5 ; Cx = 0.356762745781211; Cy = 0.328581945074458 ax = 0.154508497187474; ay = 0.475528258147577 denominator = 6 ; Cx = 0.375000000000000; Cy = 0.216506350946110 ax = 0.250000000000000; ay = 0.433012701892219 denominator = 1 ; i = 243.000000 denominator = 2 ; i = 31 171.000000 denominator = 3 ; i = 3 400 099.000000 denominator = 4 ; i = 333 293 206.000000 denominator = 5 ; i = 29 519 565 177.000000 denominator = 6 ; i = 2 384 557 783 634.000000
where :
C = Cx + Cy*i a = ax + ay*i // fixed point alpha i // number of iterations after which critical point z=0.0 reaches disc around fixed point alpha with radius AR denominator of internal angle ( in turns ) internal angle = 1/denominator
Note that attraction time i is proportional to denominator.
Now you see what means weakly attracting.
One can :
 use brutal force method ( Attracting radius < pixelSize; iteration Max big enough to let all points from interior reach target set; long time or fast computer )
 find better method (:)) if time is to long for you
Interior distance estimationEdit
TrapEdit
Estimation from interior and exteriorEdit
Julia set is a common boundary of filledin Julia set and basin of attraction of infinity.
 find points of interior/components of Kc
 find escaping points
 find boundary points using Sobel filter
It works for denominator up to 4.
Inverse iteration of repelling pointsEdit
Inverse iteration of alfa fixed point. It works good only for cuting point ( where external rays land). Other points still are not hitten.
Bof61Edit
GalleryEdit

critical orbits for internal angle from 1/1 to 1/10. True attracting directions

Nth arm stars for n from 1 to 10. Schematic attracting directions
See alsoEdit
 Image : Nonstandard Parabolic by Cheritat^{[49]}
 Julia set of parabolic case in Maxima CAS^{[50]}
 The parabolic Mandelbrot set Pascale ROESCH (joint work with C. L. PETERSEN
 PARABOLIC IMPLOSION A MINICOURSE by ArnaudCheritat
 Workshop on parabolic implosion 2010
 The renormalization for parabolic fixed points... Mitsushiro Shishikura and Hiroyuki Inou
 Dynamics of holomorphic maps: Resurgence of Fatou coordinates, and Polytime computability of Julia sets by Artem Dudko, arxiv.org : Dudko_A
 Minicourse "Analytic classification of germs of generic families unfolding a parabolic point by Christiane Rousseau
 Perspectives on Parabolic Points in Holomorphic Dynamics  The Banff International Research Station for Mathematical Innovation and Discovery (BIRS)
 Richard Oudkerk : The Parabolic Implosion for f_0(z) = z + z^{nu+1} + O(z^{nu+2})
 Perspectives on Parabolic Points in Holomorphic Dynamics Videos from BIRS Workshop 15w5082
ReferencesEdit
 ↑ Mark Braverman : On efficient computation of parabolic Julia sets
 ↑ Note on dynamically stable perturbations of parabolics by Tomoki Kawahira
 ↑ Filled Julia set in wikipedia
 ↑ Augustin Fruchard, Reinhard Sch¨afke. Composite Asymptotic Expansions and Difference Equations. Revue Africaine de la Recherche en Informatique et Math´ematiques Appliqu´ees, INRIA, 2015, 20, pp.6393. <hal01320625>
 ↑ wikipedia : Germ(mathematics)
 ↑ Fixed points of diffeomorphisms, singularities of vector fields and epsilonneighborhoods of their orbits by Maja Resman
 ↑ The moduli space of germs of generic families of analytic diffeomorphisms unfolding a parabolic fixed point by Colin Christopher, Christiane Rousseau
 ↑ wikipedia : Multiplicity (mathematics)
 ↑ Dynamics of surface homeomorphisms Topological versions of the LeauFatou flower theorem and the stable manifold theorem by Le Roux, F
 ↑ The Dynamics of Complex Polynomial Vector Fields in C by Kealey Dias
 ↑ LIMITS OF DEGENERATE PARABOLIC QUADRATIC RATIONAL MAPS by XAVIER BUFF, JEAN ECALLE, AND ADAM EPSTEIN
 ↑ Poincaré linearizers in higher dimensionsby Alastair Fletcher
 ↑ Théorie des invariants holomorphes. Thèse d'Etat, Orsay, March 1974
 ↑ Jean Ecalle in french wikipedia
 ↑ Jean Ecalle home page
 ↑ mappings by Luna Lomonaco
 ↑ MODULUS OF ANALYTIC CLASSIFICATION FOR UNFOLDINGS OF GENERIC PARABOLIC DIFFEOMORPHISMSby P. Mardesic, R. Roussarie¤ and C. Rousseau
 ↑ mathoverflow questions : the functional equation ffxxfx2
 ↑ Germ in wikipedia
 ↑ MODULUS OF ANALYTIC CLASSIFICATION FOR UNFOLDINGS OF GENERIC PARABOLIC DIFFEOMORPHISMS by P. Mardesic , R. Roussarie and C. Rousseau
 ↑ The moduli space of germs of generic families of analytic diffeomorphisms unfolding a parabolic fixed point Colin Christopher, Christiane Rousseau
 ↑ Mathoverflow : infinitesimal classification of functions near a fixed point upto conjugation
 ↑ Near parabolic renormalization for unisingular holomorphic maps by Arnaud Cheritat
 ↑ The Hausdorff dimension of the boundary of the Mandelbrot set. Tesi di Laurea Triennale
 ↑ PARABOLIC IMPLOSION A MINICOURSE by ARNAUD CHERITAT
 ↑ A FAMILY OF DEGREE 4 BLASCHKE PRODUCTS by Jordi Canela
 ↑ BOF, page 39
 ↑ Asymptotics of iterated polynomials
 ↑ commons:Category:Fractals_created_with_Mandel
 ↑ Program Mandel by Wolf Jung
 ↑ Program Mandel by Wolf Jung
 ↑ A Lösungen zu den Übungenn by Michael Becker
 ↑ Note on dynamically stable perturbations of parabolics by Tomoki Kawahira
 ↑ wikipedia : Rose (topology)
 ↑ cauliflower at MuEncy by Robert Munafo
 ↑ Circle Implodes Into Flames  video by sinflrobot
 ↑ A Topology Simplification Method For 2D Vector Fields by Xavier Tricoche Gerik Scheuermann Hans Hagen
 ↑ e ncyclopedia of math : Sector_in_the_theory_of_ordinary_differential_equations
 ↑ wikipedia : Multiplicity in mathematics
 ↑ Mandel: software for real and complex dynamics by Wolf Jung
 ↑ Local dynamics at a fixed point by Evgeny Demidov
 ↑ Parabolic Julia Sets are Polynomial Time Computable Mark Braverman
 ↑ The fixed points and periodic orbits by Evgeny Demidov
 ↑ Src code of c program for drawing parabolic Julia set
 ↑ stackexchange questions : whatistheshapeofparaboliccriticalorbit
 ↑ planetmath : San Marco fractal
 ↑ wikipedia : Douady rabbit
 ↑ planetmath : San Marco fractal
 ↑ Image : Nonstandard Parabolic by Cheritat
 ↑ Julia set of parabolic case in Maxima CAS