Critical points of a-solutions of quasilinear elliptic equations

: Martio O., Miklyukov V., Vuorinen M.

: 1999

Houston Journal of Mathematics

: 25

: 3

: 583

: 601

: 19

: 0362-1588

: http://api.elsevier.com/content/abstract/scopus_id:0040631555

Critical points of solutions to degenerate elliptic equations in R, n ≥ 2, consist of good (N-points) and bad points. Pseudoharmonic functions (n = 2), in the sense of Morse, have good points only. We give an estimate for the modulus of continuity of a generalized solution at an N-point. An analog of Sard's theorem is proved.