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Scalar Quantum Field Theory in Disordered Media

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 نشر من قبل Gabriel Menezes
 تاريخ النشر 2011
  مجال البحث فيزياء
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A free massive scalar field in inhomogeneous random media is investigated. The coefficients of the Klein-Gordon equation are taken to be random functions of the spatial coordinates. The case of an annealed-like disordered medium, modeled by centered stationary and Gaussian processes, is analyzed. After performing the averages over the random functions, we obtain the two-point causal Greens function of the model up to one-loop. The disordered scalar quantum field theory becomes qualitatively similar to a $lambdaphi^{4}$ self-interacting theory with a frequency-dependent coupling.



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