Article Contents
Article Contents

# Limit periodic upper and lower solutions in a generic sense

• * Corresponding author: Zhe Zhou

The second author is partially supported by the Key Lab of Random Complex Structures and Data Science, Chinese Academy of Sciences (Grant No. 2008DP173182) and the National Natural Science Foundation of China (Grant No. 11301512 and No. 11671382)

• The method of upper and lower solutions is a main tool to prove the existence of periodic solutions to periodic differential equations. It is known that, in general, the method does not extend to the almost periodic case. The aim of the present paper is to show that, however, something interesting survives: if the classical assumptions of the method are satisfied, then the expected existence result holds generically in the limit periodic framework.

Mathematics Subject Classification: Primary:34A34;Secondary:34C27.

 Citation:

•  A. I. Alonso , R. Obaya  and  R. Ortega , Differential equations with limit-periodic forcings, Proc. Amer. Math. Soc., 131 (2003) , 851-857.  doi: 10.1090/S0002-9939-02-06692-3. H. Brezis, Analyse Fonctionnelle -Théorie et Applications Masson, Paris, 1983. W. A. Coppel, Dichotomies in Stability Theory Lecture Notes in Mathematics, Vol. 629, Springer-Verlag, 1978. C. Corduneanu, Almost Periodic Functions 2nd English ed. , AMS Chelsea Publishing, New York, 1989. C. De Coster and P. Habets, Two-point Boundary Value Problems: Lower and Upper Solutions Mathematics in Science and Engineering 205, Elsevier, Amsterdam, 2006. A. Fink, Almost Periodic Differential Equations Springer, New York/Berlin, 1974. B. M. Levitan and V. V. Zhikov, Almost Periodic Functions and Differential Equations Cambridge Univ. Press, Cambridge, 1982. W. Magnus and S. Winkler, Hill's Equation Dover, New York, 1979. P. Martinez–Amores , J. Mawhin , R. Ortega  and  M. Willem , Generic results for the existence of nondegenerate periodic solutions of some differential systems with periodic nonlinearities, J. Differential Equation, 91 (1991) , 138-148.  doi: 10.1016/0022-0396(91)90135-V. R. Ortega , The pendulum equation: from periodic to almost periodic forcings, Differential Integral Equations, 22 (2009) , 801-814. R. Ortega  and  M. Tarallo , Almost periodic upper and lower solutions, J. Differential Equation, 193 (2003) , 343-358.  doi: 10.1016/S0022-0396(03)00130-X. K. Scmitt  and  J. R. Ward , Almost periodic solutions of nonlinear second order differential equations, Res. Math., 21 (1992) , 190-199.  doi: 10.1007/BF03323078. S. Smale , An infinite dimensional version of Sard's theorem, Amer. J. Math., 87 (1965) , 861-866.  doi: 10.1142/9789812792822_0005.

• on this site

/