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Levinsons theorem for graphs

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 نشر من قبل Andrew M. Childs
 تاريخ النشر 2011
  مجال البحث فيزياء
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We prove an analog of Levinsons theorem for scattering on a weighted (m+1)-vertex graph with a semi-infinite path attached to one of its vertices. In particular, we show that the number of bound states in such a scattering problem is equal to m minus half the winding number of the phase of the reflection coefficient (where each so-called half-bound state is counted as half a bound state).



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