Abstract
We establish existence and sharp regularity results for solutions to singular elliptic equations of the order u −β, 0 < β < 1, with gradient dependence and involving a forcing term λ f(x, u). Our approach is based on a singularly perturbed technique. We show that if the forcing parameter λ > 0 is large enough, our solution is positive. For λ small solutions vanish on a nontrivial set and therefore they exhibit free boundaries. We also establish regularity results for the free boundary and study the asymptotic behavior of the problem as \({\beta\searrow 0}\) and \({\beta\nearrow 1}\). In the former, we show that our solutions u β converge to a C 1,1 function which is a solution to an obstacle type problem. When \({\beta\nearrow 1}\) we recover the Alt-Caffarelli theory.
Similar content being viewed by others
References
Alt H.M., Caffarelli L.A.: Existence and regularity for a minimum problem with free boundary. J. Reine Angew. Math. 325, 105–144 (1981)
Alt H.M., Phillips D.: A free boundary problem for semilinear elliptic equations. J. Reine Angew. Math. 368, 63–107 (1986)
Caffarelli L.A.: The regularity of free boundaries in higher dimensions. Acta Math. 139(3–4), 155–184 (1977)
Caffarelli L.A., Rivière N.M.: On the rectifiability of domains with finite perimeter. Ann. Scuola Norm. Sup. Pisa Cl. Sci. (4) 3(2), 177–186 (1976)
Crandall M.G., Rabinowitz P.H., Tartar L.: On a Dirichlet problem with a singular nonlinearity. Commun. Partial Differ. Equ. 2(2), 193–222 (1977)
Danielli D., Petrosyan A.: A minimum problem with free boundary for a degenerate quasilinear operator. Calc. Var. Partial Differ. Equ. 23, 97–124 (2005)
Dávila J.: Global regularity for a singular equation and local H 1 minimizers of a nondifferentiable functional. Commun. Contemp. Math. 6(1), 165–193 (2004)
Dávila J., Montenegro M.: Positive versus free boundary solutions to a singular elliptic equation. J. Anal. Math. 90, 303–335 (2003)
Dávila J., Montenegro M.: Existence and asymptotic behavior for a singular parabolic equation. Trans. Am. Math. Soc. 357, 1801–1828 (2005)
Diaz J.I., Morel J.-M., Oswald L.: An elliptic equation with singular nonlinearity. Commun. Partial Differ. Equ. 12(12), 1333–1344 (1987)
Montenegro M., Ponce A.: The sub-supersolution method for weak solutions. Proc. Am. Math. Soc. 136(7), 2429–2438 (2008)
Montenegro M., Teixeira E.V.: Gradient estimates for viscosity solutions of singular fully non-linear elliptic equations. J. Funct. Anal. 259, 428–452 (2010)
Montenegro M., de Queiroz O.S.: Existence and regularity to an elliptic equation with logarithmic nonlinearity. J. Differ. Equ. 246(2), 482–511 (2009)
Moreira D.R., Teixeira E.V.: A singular perturbation free boundary problem for elliptic equations in divergence form. Calc. Var. Partial Differ. Equ. 29(2), 161–190 (2007)
Phillips D.: A minimization problem and the regularity of solutions in the presence of a free boundary. Indiana Univ. Math. J. 32, 1–17 (1983)
Phillips D.: Hausdorff measure estimates of a free boundary for a minimum problem. Commun. Partial Differ. Equ. 8, 1409–1454 (1983)
Teixeira E.V.: A variational treatment for general elliptic equations of the flame propagation type: regularity of the free boundary. Ann. Inst. H. Poincaré Anal. Non Linéaire 25(4), 633–658 (2008)
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Montenegro, M., de Queiroz, O.S. & Teixeira, E.V. Existence and regularity properties of non-isotropic singular elliptic equations. Math. Ann. 351, 215–250 (2011). https://doi.org/10.1007/s00208-010-0591-6
Received:
Revised:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00208-010-0591-6