ar X iv : 0 71 2 . 09 14 v 2 [ m at h . FA ] 2 6 Fe b 20 08 CONTRACTION SEMIGROUPS ON METRIC GRAPHS
نویسندگان
چکیده
The main objective of the present work is to study contraction semigroups generated by Laplace operators on metric graphs, which are not necessarily self-adjoint. We prove criteria for such semigroups to be continuity and positivity preserving. Also we provide a characterization of generators of Feller semi-groups on metric graphs.
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تاریخ انتشار 2008