Interplay between Approximation Theory and Renormalization Group

  title={Interplay between Approximation Theory and Renormalization Group},
  author={Vyacheslav I. Yukalov},
  journal={Physics of Particles and Nuclei},
  • V. Yukalov
  • Published 1 March 2019
  • Physics
  • Physics of Particles and Nuclei
The review presents general methods for treating complicated problems that cannot be solved exactly and whose solution encounters two major difficulties. First, there are no small parameters allowing for the safe use of perturbation theory in powers of these parameters, and even when small parameters exist, the related perturbative series are strongly divergent. Second, such perturbative series in powers of these parameters are rather short, so that the standard resummation techniques either… 
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