In recent years, the study of partial differential equations (PDEs) and their systems in graph settings has emerged as a prominent research area, driven by their significant applications in image processing and data clustering. Motivated by these developments, we aim to extend certain existence results for biharmonic-Kirchhoff systems and biharmonic systems from the Euclidean setting (continuous models) to their counterparts in locally finite graphs (discrete models). Our primary focus is on establishing the existence of infinitely many solutions for a biharmonic-Kirchhoff system defined on a locally finite graph by employing the symmetric mountain pass theorem as our key analytical tool. Under the assumption that the nonlinear term is super-quartic, we prove that the system admits infinitely many solutions. Additionally, we present analogous results for the biharmonic system. A notable observation from our study is that the results obtained in the locally finite graph setting surpass those in the Euclidean setting. This improvement is fundamentally attributed to the more favorable embedding properties inherent to the locally finite graph framework.
Citation: Xiaoyu Wang, Junping Xie, Xingyong Zhang. Infinitely many solutions of biharmonic-Kirchhoff systems on locally finite graphs[J]. Networks and Heterogeneous Media, 2026, 21(5): 1866-1889. doi: 10.3934/nhm.2026069
In recent years, the study of partial differential equations (PDEs) and their systems in graph settings has emerged as a prominent research area, driven by their significant applications in image processing and data clustering. Motivated by these developments, we aim to extend certain existence results for biharmonic-Kirchhoff systems and biharmonic systems from the Euclidean setting (continuous models) to their counterparts in locally finite graphs (discrete models). Our primary focus is on establishing the existence of infinitely many solutions for a biharmonic-Kirchhoff system defined on a locally finite graph by employing the symmetric mountain pass theorem as our key analytical tool. Under the assumption that the nonlinear term is super-quartic, we prove that the system admits infinitely many solutions. Additionally, we present analogous results for the biharmonic system. A notable observation from our study is that the results obtained in the locally finite graph setting surpass those in the Euclidean setting. This improvement is fundamentally attributed to the more favorable embedding properties inherent to the locally finite graph framework.
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