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An approximation to $δ'$ couplings on graphs

Taksu Cheon·Pavel Exner
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Abstract

We discuss a general parametrization for vertices of quantum graphs and show, in particular, how the $δ'_s$ and $δ'$ coupling at an $n$ edge vertex can be approximated by means of $n+1$ couplings of the $δ$ type provided the latter are properly scaled.

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Taksu Cheon, Pavel Exner. 2004-05-31. An approximation to $δ'$ couplings on graphs. https://doi.org/10.1088/0305-4470%2F37%2F29%2Fl01

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