# Loop-Corrected Virasoro Symmetry of 4D Quantum Gravity

### APA

He, T. (2017). Loop-Corrected Virasoro Symmetry of 4D Quantum Gravity. Perimeter Institute. https://pirsa.org/17030057

### MLA

He, Temple. Loop-Corrected Virasoro Symmetry of 4D Quantum Gravity. Perimeter Institute, Mar. 28, 2017, https://pirsa.org/17030057

### BibTex

@misc{ pirsa_PIRSA:17030057, doi = {10.48660/17030057}, url = {https://pirsa.org/17030057}, author = {He, Temple}, keywords = {Quantum Fields and Strings}, language = {en}, title = {Loop-Corrected Virasoro Symmetry of 4D Quantum Gravity}, publisher = {Perimeter Institute}, year = {2017}, month = {mar}, note = {PIRSA:17030057 see, \url{https://pirsa.org}} }

**Collection**

**Subject**

Recently a boundary energy-momentum tensor Tzz has been constructed from the soft graviton operator for any 4D quantum theory of gravity in asymptotically flat space. Up to an "anomaly" which is one-loop exact, Tzz generates a Virasoro action on the 2D celestial sphere at null infinity. Here we show by explicit construction that the effects of the IR divergent part of the anomaly can be eliminated by a one-loop renormalization that shifts Tzz.