PIRSA:23010110

On quantum corrections to the celestial operator product in gravity

APA

Bittleston, R. (2023). On quantum corrections to the celestial operator product in gravity. Perimeter Institute. https://pirsa.org/23010110

MLA

Bittleston, Roland. On quantum corrections to the celestial operator product in gravity. Perimeter Institute, Jan. 24, 2023, https://pirsa.org/23010110

BibTex

          @misc{ pirsa_23010110,
            doi = {10.48660/23010110},
            url = {https://pirsa.org/23010110},
            author = {Bittleston, Roland},
            keywords = {Quantum Fields and Strings},
            language = {en},
            title = {On quantum corrections to the celestial operator product in gravity},
            publisher = {Perimeter Institute},
            year = {2023},
            month = {jan},
            note = {PIRSA:23010110 see, \url{https://pirsa.org}}
          }
          

Roland Bittleston Perimeter Institute for Theoretical Physics

Abstract

The question of whether the holomorphic collinear singularities of graviton amplitudes define a consistent chiral algebra has garnered much recent attention. I will discuss a version of this question for infinitesimal perturbations around the self-dual sector of 4d Einstein gravity. The singularities of tree amplitudes in such perturbations do form a consistent chiral algebra. However, at loop level new poles are generated, the simplest of which are described the 1-loop effective graviton vertex. These quantum corrections violate associativity of the operator product. I will argue that this failure can be traced to an anomaly in the twistor uplift of self-dual gravity. Associativity can be restored by coupling to an unusual 4th-order gravitational axion, which cancels the anomaly by a Green-Schwarz mechanism. Alternatively, the anomaly vanishes in certain theories of self-dual gravity coupled to matter, including in self-dual supergravity.

Zoom link:  https://pitp.zoom.us/j/91979544537?pwd=Ykw4Q3lRK2ZicVhCMDhlNUxFaHhlUT09