The pic is the phase portrait of a simple "piecewise isometry". Define a map by sliding the two halves of the plane: the top half to the right; the lower half to the left and then rotate. Around each periodic point of the map there's a "periodic island". These are what are in the image...
Q&A for professional mathematicians
Joined 3 years ago, last seen today
Q&A for people studying math at any level and professionals in related fields
Joined 1 year ago, last seen 17 days ago
Q&A for professional and enthusiast programmers
Joined 2 months ago, last seen 9 days ago