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A Gribov equation for the photon Greens function

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 نشر من قبل Kosuke Odagiri
 تاريخ النشر 2009
  مجال البحث
والبحث باللغة English
 تأليف K. Odagiri




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We present a derivation of the Gribov equation for the gluon/photon Greens function D(q). Our derivation is based on the second derivative of the gauge-invariant quantity Tr ln D(q), which we interpret as the gauge-boson `self-loop. By considering the higher-order corrections to this quantity, we are able to obtain a Gribov equation which sums the logarithmically enhanced corrections. By solving this equation, we obtain the non-perturbative running coupling in both QCD and QED. In the case of QCD, alpha_S has a singularity in the space-like region corresponding to super-criticality, which is argued to be resolved in Gribovs light-quark confinement scenario. For the QED coupling in the UV limit, we obtain a propto Q^2 behaviour for space-like Q^2=-q^2. This implies the decoupling of the photon and an NJLVL-type effective theory in the UV limit.



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