The obstacle problem with singular coefficients near Dirichlet data
Annales de l'I.H.P. Analyse non linéaire, Tome 34 (2017) no. 2, pp. 293-334.

In this paper we study the behaviour of the free boundary close to its contact points with the fixed boundary B{x1=0} in the obstacle type problem

{div(x1au)=χ{u>0}inB+,u=0onB{x1=0}
where a<1, B+=B{x1>0}, B is the unit ball in Rn and n2 is an integer.

Let Γ=B+{u>0} be the free boundary and assume that the origin is a contact point, i.e. 0Γ. We prove that the free boundary touches the fixed boundary uniformly tangentially at the origin, near to the origin it is the graph of a C1 function and there is a uniform modulus of continuity for the derivatives of this function.

DOI : 10.1016/j.anihpc.2015.12.003
Classification : 35R35, 35J60
Mots clés : Free boundary, Obstacle problem, Singular coefficient, Regularity of free boundaries
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     title = {The obstacle problem with singular coefficients near {Dirichlet} data},
     journal = {Annales de l'I.H.P. Analyse non lin\'eaire},
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Shahgholian, Henrik; Yeressian, Karen. The obstacle problem with singular coefficients near Dirichlet data. Annales de l'I.H.P. Analyse non linéaire, Tome 34 (2017) no. 2, pp. 293-334. doi : 10.1016/j.anihpc.2015.12.003. http://www.numdam.org./articles/10.1016/j.anihpc.2015.12.003/

[1] Caffarelli, L. The obstacle problem revisited, J. Fourier Anal. Appl., Volume 4 (1998) no. 4–5, pp. 383–402 | MR | Zbl

[2] Caffarelli, L.; Silvestre, L. An extension problem related to the fractional Laplacian, Commun. Partial Differ. Equ., Volume 32 (2007) no. 7–9, pp. 1245–1260 | MR | Zbl

[3] Daskalopoulos, P.; Feehan, P.M.N. C1,1 regularity for degenerate elliptic obstacle problems | arXiv | Zbl

[4] Fabes, E.B.; Kenig, C.E.; Serapioni, R.P. The local regularity of solutions of degenerate elliptic equations, Commun. Partial Differ. Equ., Volume 7 (1982) no. 1, pp. 77–116 | DOI | MR | Zbl

[5] Gilbarg, D.; Trudinger, N. Elliptic Partial Differential Equations of Second Order, Classics in Mathematics, Springer-Verlag, Berlin, 2001 (Reprint of the 1998 edition xiv+517 pp) | MR | Zbl

[6] Petrosyan, A.; Shahgholian, H.; Uraltseva, N. Regularity of Free Boundaries in Obstacle-Type Problems, Graduate Studies in Mathematics, vol. 136, American Mathematical Society, Providence, RI, 2012 (x+221 pp) | DOI | MR | Zbl

[7] Rubel, L.A. Necessary and sufficient conditions for Carlson's theorem on entire functions, Trans. Am. Math. Soc., Volume 83 (1956), pp. 417–429 | MR | Zbl

[8] Shahgholian, H.; Uraltseva, N. Regularity properties of a free boundary near contact points with the fixed boundary, Duke Math. J., Volume 116 (2003) no. 1, pp. 1–34 | DOI | MR | Zbl

[9] Weiss, G.S. Partial regularity for weak solutions of an elliptic free boundary problem, Commun. Partial Differ. Equ., Volume 23 (1998) no. 3–4, pp. 439–455 | MR | Zbl

[10] Yang, R. On higher order extensions for the fractional Laplacian | arXiv

[11] Yeressian, K. Nondegeneracy in the obstacle problem with a degenerate force term, Interfaces Free Bound., Volume 17 (2015) no. 2, pp. 233–244 | DOI | MR | Zbl

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