Abstract
We consider the elliptic problem
We consider the elliptic problem
P. H. Rabinowitz, Minimax Methods in Critical Point Theory with Applications to Differential Equations, vol. 65 of CBMS Regional Conference Series in Mathematics, American Mathematical Society, Providence, RI, USA, 1986.
View at: Zentralblatt MATH | MathSciNetA. Ambrosetti and P. H. Rabinowitz, “Dual variational methods in critical point theory and applications,” Journal of Functional Analysis, vol. 14, no. 4, pp. 349–381, 1973.
View at: Publisher Site | Google Scholar | Zentralblatt MATH | MathSciNetM. Willem, Minimax Theorems, vol. 24 of Progress in Nonlinear Differential Equations and Their Applications, Birkhäuser, Boston, Mass, USA, 1996.
View at: Zentralblatt MATH | MathSciNetH.-C. Wang and T.-F. Wu, “Symmetry breaking in a bounded symmetry domain,” NoDEA. Nonlinear Differential Equations and Applications, vol. 11, no. 3, pp. 361–377, 2004.
View at: Publisher Site | Google Scholar | MathSciNetH. Berestycki and P.-L. Lions, “Nonlinear scalar field equations. I. Existence of a ground state,” Archive for Rational Mechanics and Analysis, vol. 82, no. 4, pp. 313–345, 1983.
View at: Google Scholar | Zentralblatt MATH | MathSciNetW. C. Lien, S. Y. Tzeng, and H.-C. Wang, “Existence of solutions of semilinear elliptic problems on unbounded domains,” Differential and Integral Equations, vol. 6, no. 6, pp. 1281–1298, 1993.
View at: Google Scholar | Zentralblatt MATH | MathSciNetK.-J. Chen and H.-C. Wang, “A necessary and sufficient condition for Palais-Smale conditions,” SIAM Journal on Mathematical Analysis, vol. 31, no. 1, pp. 154–165, 1999.
View at: Publisher Site | Google Scholar | Zentralblatt MATH | MathSciNetM. A. Del Pino and P. L. Felmer, “Local mountain passes for semilinear elliptic problems in unbounded domains,” Calculus of Variations and Partial Differential Equations, vol. 4, no. 2, pp. 121–137, 1996.
View at: Google Scholar | Zentralblatt MATH | MathSciNetM. A. Del Pino and P. L. Felmer, “Least energy solutions for elliptic equations in unbounded domains,” Proceedings of the Royal Society of Edinburgh. Section A, vol. 126, no. 1, pp. 195–208, 1996.
View at: Google Scholar | Zentralblatt MATH | MathSciNetM. K. Kwong, “Uniqueness of positive solutions of in ,” Archive for Rational Mechanics and Analysis, vol. 105, no. 3, pp. 243–266, 1989.
View at: Publisher Site | Google Scholar | Zentralblatt MATH | MathSciNetV. Benci and G. Cerami, “Positive solutions of some nonlinear elliptic problems in exterior domains,” Archive for Rational Mechanics and Analysis, vol. 99, no. 4, pp. 283–300, 1987.
View at: Publisher Site | Google Scholar | Zentralblatt MATH | MathSciNetA. Bahri and P.-L. Lions, “On the existence of a positive solution of semilinear elliptic equations in unbounded domains,” Annales de l'Institut Henri Poincaré. Analyse Non Linéaire, vol. 14, no. 3, pp. 365–413, 1997.
View at: Google Scholar | Zentralblatt MATH | MathSciNetM. J. Esteban and P.-L. Lions, “Existence and nonexistence results for semilinear elliptic problems in unbounded domains,” Proceedings of the Royal Society of Edinburgh. Section A, vol. 93, no. 1-2, pp. 1–14, 1982-1983.
View at: Google Scholar | Zentralblatt MATH | MathSciNetD.-M. Cao, “Positive solution and bifurcation from the essential spectrum of a semilinear elliptic equation on ,” Nonlinear Analysis, vol. 15, no. 11, pp. 1045–1052, 1990.
View at: Publisher Site | Google Scholar | Zentralblatt MATH | MathSciNetA. Bahri and Y. Y. Li, “On a min-max procedure for the existence of a positive solution for certain scalar field equations in ,” Revista Matemática Iberoamericana, vol. 6, no. 1-2, pp. 1–15, 1990.
View at: Google Scholar | Zentralblatt MATH | MathSciNetT.-F. Wu, “Multiplicity of single-bump solutions for semilinear elliptic equations in multi-bump domains,” Nonlinear Analysis, vol. 59, no. 6, pp. 973–992, 2004.
View at: Publisher Site | Google Scholar | MathSciNetX. P. Zhu, “A perturbation result on positive entire solutions of a semilinear elliptic equation,” Journal of Differential Equations, vol. 92, no. 2, pp. 163–178, 1991.
View at: Publisher Site | Google Scholar | Zentralblatt MATH | MathSciNetD.-M. Cao and H.-S. Zhou, “Multiple positive solutions of nonhomogeneous semilinear elliptic equations in ,” Proceedings of the Royal Society of Edinburgh. Section A, vol. 126, no. 2, pp. 443–463, 1996.
View at: Google Scholar | Zentralblatt MATH | MathSciNetL. Jeanjean, “Two positive solutions for a class of nonhomogeneous elliptic equations,” Differential and Integral Equations, vol. 10, no. 4, pp. 609–624, 1997.
View at: Google Scholar | Zentralblatt MATH | MathSciNetS. Adachi and K. Tanaka, “Multiple positive solutions for nonhomogeneous elliptic equations,” Nonlinear Analysis, vol. 47, no. 6, pp. 3783–3793, 2001.
View at: Publisher Site | Google Scholar | Zentralblatt MATH | MathSciNetS. Adachi and K. Tanaka, “Four positive solutions for the semilinear elliptic equation: in ,” Calculus of Variations and Partial Differential Equations, vol. 11, no. 1, pp. 63–95, 2000.
View at: Publisher Site | Google Scholar | Zentralblatt MATH | MathSciNetH.-L. Lin, H.-C. Wang, and T.-F. Wu, “A Palais-Smale approach to Sobolev subcritical operators,” Topological Methods in Nonlinear Analysis, vol. 20, no. 2, pp. 393–407, 2002.
View at: Google Scholar | Zentralblatt MATH | MathSciNetG. Tarantello, “On nonhomogeneous elliptic equations involving critical Sobolev exponent,” Annales de l'Institut Henri Poincaré. Analyse Non Linéaire, vol. 9, no. 3, pp. 281–304, 1992.
View at: Google Scholar | Zentralblatt MATH | MathSciNetH. Brézis and E. Lieb, “A relation between pointwise convergence of functions and convergence of functionals,” Proceedings of the American Mathematical Society, vol. 88, no. 3, pp. 486–490, 1983.
View at: Google Scholar | Zentralblatt MATH | MathSciNetI. Ekeland, “On the variational principle,” Journal of Mathematical Analysis and Applications, vol. 47, no. 2, pp. 324–353, 1974.
View at: Publisher Site | Google Scholar | Zentralblatt MATH | MathSciNet