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Effective Field Theory with a Variable Ultraviolet Cutoff

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 نشر من قبل Nikolaos Tetradis
 تاريخ النشر 2008
  مجال البحث
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 تأليف Nikolaos Tetradis




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The properties of strongly gravitating systems suggest that field theory overcounts the states of a system. Reducing the number of degrees of freedom, without abandoning the notion of effective field theory, may be achieved through a connection between the ultraviolet and infrared cutoffs. We provide an implementation of this idea within the Wilsonian approach to the renormalization group. We derive an exact flow equation that describes the evolution of the effective action. We discuss the implications for the existence of infrared fixed points and the running of couplings. We also give an alternative derivation in the context of the perturbative renormalization group.



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