5 papers
Gravitational Hilbert spaces: invariant and co-invariant states, inner products, gauge-fixing, and BRST
Jesse Held, Henry Maxfield
Hilbert spaces in theories of gravity are notoriously subtle due to the Hamiltonian constraints, particularly regarding the inner product. To demystify this subject, we review and…
A menagerie of Schwarzians: coadjoint orbits of Virasoro and near-dS quantum gravity
Henry Maxfield
The Schwarzian theory, which governs the universal low-energy dynamics of near-extremal black holes and the SYK model, can be characterised as an integral over a particular coadjoi…
The Hilbert space of de Sitter JT: a case study for canonical methods in quantum gravity
Jesse Held, Henry Maxfield
We study de Sitter JT gravity in the canonical formulation to illustrate constructions of Hilbert spaces in quantum gravity, which is challenging due to the Hamiltonian constraints…
An apologia for islands
Stefano Antonini, Chang-Han Chen, Henry Maxfield +1
Entanglement islands have played a key role in the recent derivation of the Page curve and other progress on the black hole information problem. Arising from the inclusion of conne…
On the non-perturbative bulk Hilbert space of JT gravity
Luca V. Iliesiu, Adam Levine, Henry W. Lin +2
What is the bulk Hilbert space of quantum gravity? In this paper, we resolve this problem in 2d JT gravity, both with and without matter, providing an explicit definition of a non-…