A maximum principle related to level surfaces of solutions of parabolic equations

Carlo Pucci
1989 Journal of the Australian Mathematical Society  
Let u be a solution of a parabolic equation ut = F (v, Du, D 2 u). Under convenient hypotheses it is proved that the angle between a given direction and the normal to the level surfaces of u(-,t) satisfies a maximum principle. 1980 Mathematics subject classification (Amer. Math. Soc.) (1985 Revision): 35 B 50.
doi:10.1017/s1446788700030342 fatcat:ocqhsbyubzet7l32b3oehjugrm