Julia Sets and the Mandelbrot Set

Universality of the Mandelbrot set

For the details of the Curry-Garnett-Sullivan experiment, first note that for all values of c, z = 1 is a root of the polynomial fc(z) = z3 + (c - 1)z - c.
fc(1) = 13 + (c - 1)⋅1 - c
= 1 + (c - 1) - c
= 0
Always starting with z0 = 0, Curry, Garnett, and Sullivan painted c
  black if Newton's method converged to 1,
  white if it converged to some other root of fc(z), and
  grey if it converged to a cycle of at least 2 points.
Here are their results, with vertical and horizontal ranges -2 to 2.
On the left below is a magnification of the blob on the top of the picture; on the right, a magnification of the little grey region.
It's the Mandelbrot set, yet again.
Keep in mind the function being iterated is Newton's method for a cubic polynomial. It is not at all like z2 + c. Yet here's the Mandelbrot set, yet again.

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