Logo
ScienceStack
Table of Contents
Fetching ...
Sign In

Models of AdS_2 Backreaction and Holography

Ahmed Almheiri, Joseph Polchinski

TL;DR

The paper develops solvable 1+1D dilaton-gravity models that flow from a Lifshitz-type UV to AdS2 in the IR to study backreaction in AdS2 holography. It computes boundary scalar correlators, shows backreaction induces a relevant, nonconformal deformation in the IR, and analyzes black-hole thermodynamics with large-N matter, finding consistent entropies with holographic and Bekenstein-Hawking counts while identifying density-of-states puzzles. The results demonstrate that AdS2 backreaction is a universal, strong IR effect in compact transverse spaces and illuminate how finite-energy states and time reparametrizations shape boundary dynamics. The work provides a controlled setting to probe AdS2 holography, backreaction, and potential remnants, with prospects for including gravitational loops and noncompact transverse spaces in future studies.

Abstract

We develop models of 1+1 dimensional dilaton gravity describing flows to $AdS_2$ from higher dimensional $AdS$ and other spaces. We use these to study the effects of backreaction on holographic correlators. We show that this scales as a relevant effect at low energies, for compact transverse spaces. We also discuss effects of matter loops, as in the CGHS model.

Models of AdS_2 Backreaction and Holography

TL;DR

The paper develops solvable 1+1D dilaton-gravity models that flow from a Lifshitz-type UV to AdS2 in the IR to study backreaction in AdS2 holography. It computes boundary scalar correlators, shows backreaction induces a relevant, nonconformal deformation in the IR, and analyzes black-hole thermodynamics with large-N matter, finding consistent entropies with holographic and Bekenstein-Hawking counts while identifying density-of-states puzzles. The results demonstrate that AdS2 backreaction is a universal, strong IR effect in compact transverse spaces and illuminate how finite-energy states and time reparametrizations shape boundary dynamics. The work provides a controlled setting to probe AdS2 holography, backreaction, and potential remnants, with prospects for including gravitational loops and noncompact transverse spaces in future studies.

Abstract

We develop models of 1+1 dimensional dilaton gravity describing flows to from higher dimensional and other spaces. We use these to study the effects of backreaction on holographic correlators. We show that this scales as a relevant effect at low energies, for compact transverse spaces. We also discuss effects of matter loops, as in the CGHS model.

Paper Structure

This paper contains 15 sections, 80 equations, 1 figure.

Table of Contents

  1. Introduction
  2. AdS$_2$ back-reaction models
  3. The models
  4. Conformal gauge
  5. Static vacuum solutions
  6. The $\lambda = 0$, $U(\Phi) = C-A \Phi^2$ model
  7. Vacuum solutions
  8. Solutions with matter
  9. Backreaction in $AdS_2$
  10. Scalar field holography
  11. The black hole and matter in equilibrium
  12. Backreaction of matter
  13. The renormalized stress tensor
  14. Thermodynamic quantities
  15. Discussion

Figures (1)

  • Figure 1: The global spacetime for an ingoing matter pulse ($z$ increases to the left). Before the pulse the solution is the vacuum geometry (\ref{['glovac']}), with a singularity outside the Poincaré patch. After the pulse there is the black hole (\ref{['phi2']}). For pulses of small amplitude, the singularity remains timelike and a second timelike singularity emerges from the boundary. For pulses of large amplitude, the singularity is spacelike. The orange shaded portion is the exterior of the blackhole.