[NT/RBRC hybrid seminar] Soft-collinear effective field theory for gravity

by Dr Robert Szafron (BNL)

Friday 20 May 2022, 11:00 → 12:00 US/Eastern

Large Seminar Room ( https://bnl.zoomgov.com/j/1617203107?pwd=MUpFWHdtT2hYUjk1RTVPN3U1bnBHUT09)

The soft limits of gauge theories and perturbative gravity are surprisingly similar despite the different gauge structures of both theories. However, unlike gauge theory, gravity does not feature any collinear divergences. Thus, it is interesting to explore infra-red limits of gravity and gauge theories from the perspective of an effective field theory approach. While the soft-collinear effective field theory for QCD is relatively well understood, little is known about the corresponding formulation for gravity. 
I will present the construction of SCET gravity beyond leading power and emphasize the fundamental role of emergent gauge symmetries. Exploring striking similarities with QCD, I will show how to perform systematic operator-based expansion near the light cone. I will use the SCET formalism to derive the subleading soft theorem, demonstrate its universal structure and discuss how power-counting restricts loop corrections in gravity.