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RG of GR from On-shell Amplitudes

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 نشر من قبل Pietro Baratella
 تاريخ النشر 2021
  مجال البحث فيزياء
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We study the renormalization group of generic effective field theories that include gravity. We follow the on-shell amplitude approach, which provides a simple and efficient method to extract anomalous dimensions avoiding complications from gauge redundancies. As an invaluable tool we introduce a modified helicity $tilde{h}$ under which gravitons carry one unit instead of two. With this modified helicity we easily explain old and uncover new non-renormalization theorems for theories including gravitons. We provide complete results for the one-loop gravitational renormalization of a generic minimally coupled gauge theory with scalars and fermions and all orders in $M_{Pl}$, as well as for the renormalization of dimension-six operators including at least one graviton, all up to four external particles.

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