Julia sets

The Julia set is closely related to the Mandelbrot set. For each complex number c, the Julia set J_c is the set of complex numbers z whose orbit under iteration of f_c(z) = z^2+c is bounded. The Julia set fixes c and allows the initial point z, whose orbit gets computed, to vary. The set J_c comprises those values z whose orbits are bounded.

Use the cr and ci sliders to set the real and imaginary parts of the constant c, then press Go to view J_c. The program otherwise is controlled the same as the previous Mandelbrot program.

Julia sets

Here are the locations of some interesting Julia sets:1

  • c=-0.79+0.15i
  • c=-0.162 + 1.04i
  • c = 0.3 - 0.01i
  • c = -1.476 + 0i
  • c = -0.12 - 0.77i
  • c = 0.28 + 0.008i

Use the text fields for cr and ci to input these values. Increase levels for maximum detail.