Saved in:
Bibliographic Details
Main Authors: Griguolo, Luca, Papalini, Jacopo, Russo, Lorenzo, Seminara, Domenico
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2512.21774
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866911527411384320
author Griguolo, Luca
Papalini, Jacopo
Russo, Lorenzo
Seminara, Domenico
author_facet Griguolo, Luca
Papalini, Jacopo
Russo, Lorenzo
Seminara, Domenico
contents The formulation of two-dimensional quantum gravity at finite cutoff remains an open problem. We revisit this question in JT gravity from two perspectives: the closed-channel bulk path integral and the path integral over boundary curves. First, we study the radial evolution of a closed universe and derive the trumpet wavefunction as a transition amplitude between a geodesic boundary and a finite Dirichlet boundary. Our analysis recovers the Hartle--Hawking wavefunction without imposing asymptotic boundary conditions, allowing the trumpet to be glued to a cap wavefunction to reconstruct the smooth disk. Second, we derive an exact Riccati equation for the extrinsic curvature of a finite-cutoff boundary curve in the Euclidean Poincaré disk. A WKB expansion of this equation yields all perturbative corrections in the cutoff parameter and captures nonperturbative effects. From this, we compute the quadratic boundary action and the one-loop partition function at finite cutoff, finding agreement with both the bulk approach and the expected one-loop effective action for the $T\bar{T}$ deformation of the Schwarzian theory. Extracting lessons from JT gravity, we then argue that similar relationships hold for general dilaton gravities with arbitrary potentials $V(ϕ)$ and propose an exact expression for their finite cutoff partition functions. We finally investigate several signatures of UV completeness in these settings, introducing a canonical quantization approach within the finite cutoff framework.
format Preprint
id arxiv_https___arxiv_org_abs_2512_21774
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle A new perspective on dilaton gravity at finite cutoff
Griguolo, Luca
Papalini, Jacopo
Russo, Lorenzo
Seminara, Domenico
High Energy Physics - Theory
The formulation of two-dimensional quantum gravity at finite cutoff remains an open problem. We revisit this question in JT gravity from two perspectives: the closed-channel bulk path integral and the path integral over boundary curves. First, we study the radial evolution of a closed universe and derive the trumpet wavefunction as a transition amplitude between a geodesic boundary and a finite Dirichlet boundary. Our analysis recovers the Hartle--Hawking wavefunction without imposing asymptotic boundary conditions, allowing the trumpet to be glued to a cap wavefunction to reconstruct the smooth disk. Second, we derive an exact Riccati equation for the extrinsic curvature of a finite-cutoff boundary curve in the Euclidean Poincaré disk. A WKB expansion of this equation yields all perturbative corrections in the cutoff parameter and captures nonperturbative effects. From this, we compute the quadratic boundary action and the one-loop partition function at finite cutoff, finding agreement with both the bulk approach and the expected one-loop effective action for the $T\bar{T}$ deformation of the Schwarzian theory. Extracting lessons from JT gravity, we then argue that similar relationships hold for general dilaton gravities with arbitrary potentials $V(ϕ)$ and propose an exact expression for their finite cutoff partition functions. We finally investigate several signatures of UV completeness in these settings, introducing a canonical quantization approach within the finite cutoff framework.
title A new perspective on dilaton gravity at finite cutoff
topic High Energy Physics - Theory
url https://arxiv.org/abs/2512.21774