TY - JOUR A1 - Hinz, Michael A1 - Schwarz, Michael T1 - A note on Neumann problems on graphs JF - Positivity N2 - We discuss Neumann problems for self-adjoint Laplacians on (possibly infinite) graphs. Under the assumption that the heat semigroup is ultracontractive we discuss the unique solvability for non-empty subgraphs with respect to the vertex boundary and provide analytic and probabilistic representations for Neumann solutions. A second result deals with Neumann problems on canonically compactifiable graphs with respect to the Royden boundary and provides conditions for unique solvability and analytic and probabilistic representations. KW - Graphs KW - Discrete Dirichlet forms KW - Neumann problem KW - Royden boundary Y1 - 2022 U6 - https://doi.org/10.1007/s11117-022-00930-0 SN - 1385-1292 SN - 1572-9281 VL - 26 IS - 4 PB - Springer CY - Dordrecht ER - TY - JOUR A1 - Keller, Matthias A1 - Lenz, Daniel A1 - Schmidt, Marcel A1 - Schwarz, Michael T1 - Boundary representation of Dirichlet forms on discrete spaces JF - Journal de Mathématiques Pures et Appliquées N2 - We describe the set of all Dirichlet forms associated to a given infinite graph in terms of Dirichlet forms on its Royden boundary. Our approach is purely analytical and uses form methods. (C) 2018 Elsevier Masson SAS. KW - Dirichlet form KW - Royden boundary KW - Infinite graph KW - Harmonic measure KW - Trace Dirichlet form Y1 - 2019 U6 - https://doi.org/10.1016/j.matpur.2018.10.005 SN - 0021-7824 SN - 1776-3371 VL - 126 SP - 109 EP - 143 PB - Elsevier CY - Amsterdam ER -