Extremal functions for the second-order Sobolev inequality on Cayley graphs
摘要
In this paper, we introduce the second-order Sobolev spaces on Cayley graphs. We also prove the second-order Sobolev inequalities and the existence of extremal functions for best constants in supercritical cases. As an application, we derive positive ground state solutions for the p-biharmonic equations and the Lane-Emden systems on Cayley graphs of groups of polynomial growth.