Imbert, Cyril Some regularity results for anisotropic motion of fronts. (English) Zbl 1034.35159 Differ. Integral Equ. 15, No. 10, 1263-1271 (2002). This paper concerns the regularity of fronts propagating in the environment being anisotropic and inhomogeneous. It is proved that under appropriate assumptions there is at most one normal direction at each point of the front. With the help of this result the author shows that convex fronts are \(C^{1,1}\). The level-set approach, together with the theory of viscosity solutions, is used. The fronts are regarded as level sets of viscosity solutions of the anisotropic mean curvature equations. In particular, the author uses the results of Y. Giga, S. Goto, H. Ishii, and M.-H. Sato [Indiana Univ. Math. J. 40, 443–470 (1991; Zbl 0836.35009)] concerning existence, uniqueness, and convexity of viscosity solutions. Reviewer: Shigeru Sakaguchi (Ehime) Cited in 1 Document MSC: 35R35 Free boundary problems for PDEs 35K55 Nonlinear parabolic equations 35B65 Smoothness and regularity of solutions to PDEs 49L25 Viscosity solutions to Hamilton-Jacobi equations in optimal control and differential games Keywords:regularity of fronts; anisotropic mean curvature; viscosity solutions Citations:Zbl 0836.35009 PDFBibTeX XMLCite \textit{C. Imbert}, Differ. Integral Equ. 15, No. 10, 1263--1271 (2002; Zbl 1034.35159)