Bifurcation of Boundary Wavefronts for Some Graphs
This Demonstration shows bifurcations of wavefronts generated by some curves with and without boundaries (red points). Wavefronts are generated by a curve and its normal boundary. We are concerned with local bifurcations on initial wavefronts around a point as a function of time, that is, behavior of the shape of a wavefront around a red point at times when the shape has a singularity.
The theory of bifurcations of generic wavefronts is given in .
 T. Tsukada, "Bifurcations of Wavefronts on r-Corners : Semi-Local Classification," Methods and Applications of Analysis, 18(3), pp. 303–334 (2011).
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