Workshop on Symmetries and Gravity

Dates: January 21–24, 2025

Location: Harvard CMSA, 20 Garden Street, Cambridge, MA 02138

Organizers: Ibrahima Bah (Johns Hopkins University), Patrick Jefferson (Johns Hopkins University), Yiming Chen (Stanford University)

Description: There is a widespread belief, that has its origins in work from the 70s, that a theory of quantum gravity cannot admit global symmetries. Traditionally, this was seen only as a qualitative statement about ordinary symmetries, but there have since been a number of developments that have both widened its scope and sharpened its implications. Recent work has greatly broadened the definition of global symmetries, and characterizes them in terms of topological operators in quantum systems. Concurrently, insights from quantum gravity have suggested ways to quantify the extent of global symmetry violation. Additionally, advances in the swampland program, along with amplitudes and bootstrap techniques, have shown ways to turn high-energy statements into constraints on low-energy effective field theories. In string theory, there are more concrete statements on charge violation in gravity, with proofs in limited context. In general, however, “no global symmetries in quantum gravity” continues to be an open conjecture with broad implications on the nature of quantum gravity and low-energy effective field theory. The main goal of the meeting is to bring together experts in the various arenas of research above, to reassess and develop new strategies for making progress on this long-standing open problem. Some objectives include understanding the violation of various generalized and categorical symmetries in gravity more cohesively, and putting concrete bounds on global charge-violating amplitudes at low energies.

Partially funded by the Simons Collaboration on Global Categorical Symmetries.

Confirmed Participants

• Tom Banks, Rutgers University
• Federico Bonetti, Durham University
• Jeevan Chandra, Cornell
• Christian Copetti, Oxford
• Matilda Delgado, IFT
• Iñaki Garcia-Etxebarria, Durham University
• Kelian Haring, CERN
• Jonathan Heckman, University of Pennsylvania
• Aidan Herderschee, IAS
• Theo Johnson-Freyd, Dalhousie University
• Yue-Zhou Li, Princeton
• Jacob McNamara, Caltech
• Miguel Montero, IFT
• Hirosi Ooguri, Caltech
• Leonardo Rastelli, Stony Brook University
• Grant Remmen, New York University
• Konstantinos Roumpedakis, Johns Hopkins University
• Tom Rudelius, Durham University
• Edgar Shaghoulian, UC Santa Cruz
• Shu-Heng Shao, Stony Brook University and MIT
• Adar Sharon, Simons Center for Geometry and Physics, Stony Brook
• Irene Valenzuela, IFT and CERN
• Thomas Waddleton, Johns Hopkins University