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Bound states of the $phi^4$ model via the nonperturbative renormalization group

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 نشر من قبل Federico Benitez
 تاريخ النشر 2016
  مجال البحث فيزياء
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Using the nonperturbative renormalization group, we study the existence of bound states in the symmetry-broken phase of the scalar $phi^4$ theory in all dimensions between two and four and as a function of the temperature. The accurate description of the momentum dependence of the two-point function, required to get the spectrum of the theory, is provided by means of the Blaizot--Mendez-Galain--Wschebor approximation scheme. We confirm the existence of a bound state in dimension three, with a mass within 1% of previous Monte-Carlo and numerical diagonalization values.



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