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A product formula and combinatorial field theory

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 نشر من قبل Allan I. Solomon
 تاريخ النشر 2004
  مجال البحث فيزياء
والبحث باللغة English
 تأليف A. Horzela




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We treat the problem of normally ordering expressions involving the standard boson operators a, a* where [a,a*]=1. We show that a simple product formula for formal power series - essentially an extension of the Taylor expansion - leads to a double exponential formula which enables a powerful graphical description of the generating functions of the combinatorial sequences associated with such functions - in essence, a combinatorial field theory. We apply these techniques to some examples related to specific physical Hamiltonians.



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