Timelike Boundaries in Classical and Quantum Gravity – December 8-12, 2025

Organized by:

  • Michael Anderson (Stony Brook University)
  • Dionysios Anninos (King’s College London)
  • Damian Galante (King’s College London)
  • Edgar Shaghoulian (UC Santa Cruz)
  • Eva Silverstein (Stanford University)

Asymptotic boundaries play a crucial role in the theory of general relativity. Foundational examples include the null boundary of asymptotically flat spacetimes and the conformal boundary of Anti-de Sitter space. However, not all physical settings allow for such asymptotic boundaries. In cosmology the topology of spacetime is not known, and may contain finite timelike boundaries enabling a quasilocal holographic formulation capturing the microphysics of the cosmological horizon. Finite timelike boundaries can be considered in spacetimes with arbitrary cosmological constant, and they lead to a host of fascinating questions involving well-posedness, stability, and quantum-mechanical aspects. Building from recent progress on these problems, the workshop will focus on this rapidly developing area which lies at the interface between mathematics and theoretical physics.