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arXiv · 1205.5941

Momentum operators on graphs

Pavel Exner
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Abstract

We discuss ways in which momentum operators can be introduced on an oriented metric graph. A necessary condition appears to the balanced property, or a matching between the numbers of incoming and outgoing edges; we show that a graph without an orientation, locally finite and at most countably infinite, can made balanced oriented \emph{iff} the degree of each vertex is even. On such graphs we construct families of momentum operators; we analyze their spectra and associated unitary groups. We also show that the unique continuation principle does not hold here.

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Pavel Exner. 2012-05-27. Momentum operators on graphs. https://arxiv.org/abs/1205.5941

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