RT Journal Article T1 Dirichlet systems with discrete relativistic operator A1 Cabada Fernández, Alberto A1 Jebelean, Petru A1 Şerban, Călin K1 Difference Equations K1 Discrete relativistic operator K1 Variational Methods AB We are concerned with Dirichlet systems involving the relativistic discrete operator$$ u \mapsto \Delta \left [ \frac{\Delta u(n-1)}{\sqrt{1 - |\Delta u(n-1)|^2}} \right ] \qquad \left (n \in \{1, \ldots, T\} \right ).$$Here, for $u:\{0, \ldots, T+1\}\to \mathbb{R}^N,$ we denote $\Delta u(n-1):=u(n)-u(n-1)$. Besides an "universal" existence result for a system with a general nonlinearity, we obtain multiplicity of solutions for systems with parameterized nonlinearities. Our approaches mainly rely on Brouwer degree arguments and critical point theory for convex, lower semicontinuous perturbations of $C^1$-functionals. PB Wiley SN 0024-6093 YR 2023 FD 2023-12-26 LK https://hdl.handle.net/10347/39892 UL https://hdl.handle.net/10347/39892 LA eng NO Cabada, A., Jebelean, P. and Şerban, C. (2024), Dirichlet systems with discrete relativistic operator. Bull. London Math. Soc., 56: 1149-1168 NO This is the Author Accepted Manuscript version of the following article: Cabada, A., Jebelean, P. and Şerban, C. (2024), Dirichlet systems with discrete relativistic operator. Bull. London Math. Soc., 56: 1149-1168, which has been published in final form at https://doi.org/10.1112/blms.12986 NO The first author was supported by Grant PID2020-113275GB-I00 funded by MCIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe” of the “European Union”. DS Minerva RD 28 abr 2026