skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: The Hilbert space of quantum gravity is locally finite-dimensional

Journal Article · · International Journal of Modern Physics D
 [1]; ORCiD logo [1];  [1]
  1. California Inst. of Technology (CalTech), Pasadena, CA (United States). Walter Burke Inst. for Theoretical Physics

In this article, we argue in a model-independent way that the Hilbert space of quantum gravity is locally finite-dimensional. In other words, the density operator describing the state corresponding to a small region of space, when such a notion makes sense, is defined on a finite-dimensional factor of a larger Hilbert space. Because quantum gravity potentially describes superpositions of different geometries, it is crucial that we associate Hilbert-space factors with spatial regions only on individual decohered branches of the universal wave function. We discuss some implications of this claim, including the fact that quantum-field theory cannot be a fundamental description of nature.

Research Organization:
California Institute of Technology (CalTech), Pasadena, CA (United States)
Sponsoring Organization:
USDOE Office of Science (SC), High Energy Physics (HEP)
Grant/Contract Number:
SC0011632
OSTI ID:
1598796
Journal Information:
International Journal of Modern Physics D, Vol. 26, Issue 12; ISSN 0218-2718
Publisher:
World ScientificCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 19 works
Citation information provided by
Web of Science

References (25)

A covariant entropy conjecture journal July 1999
Wormholes, emergent gauge fields, and the weak gravity conjecture journal January 2016
Positive vacuum energy and the N -bound journal November 2000
The stretched horizon and black hole complementarity journal October 1993
Remarks on entanglement entropy for gauge fields journal April 2014
Modern Tests of Lorentz Invariance journal September 2005
Black Holes and Entropy journal April 1973
Universal upper bound on the entropy-to-energy ratio for bounded systems journal January 1981
From physical symmetries to emergent gauge symmetries journal October 2016
De Sitter Holography with a Finite Number of States journal January 2005
Cosmological Breaking of Supersymmetry? conference November 2011
Space from Hilbert space: Recovering geometry from bulk entanglement journal January 2017
Emergent Gravity Requires Kinematic Nonlocality journal January 2015
Observables, gravitational dressing, and obstructions to locality and subsystems journal November 2016
Cosmological Breaking of Supersymmetry? journal February 2001
Disturbing Implications of a Cosmological Constant journal October 2002
Black Holes and Entropy book September 2019
Remarks on entanglement entropy for gauge fields text January 2013
Wormholes, Emergent Gauge Fields, and the Weak Gravity Conjecture text January 2015
Space from Hilbert Space: Recovering Geometry from Bulk Entanglement text January 2016
From physical symmetries to emergent gauge symmetries text January 2016
Disturbing Implications of a Cosmological Constant text January 2002
De Sitter Holography with a Finite Number of States text January 2004
The Stretched Horizon and Black Hole Complementarity text January 1993
A Covariant Entropy Conjecture text January 1999

Cited By (6)

Spacetime granularity from finite-dimensionality of local observable algebras journal January 2020
Towards space from Hilbert space: finding lattice structure in finite-dimensional quantum systems journal December 2018
How low can vacuum energy go when your fields are finite-dimensional? journal October 2019
Quantum-First Gravity journal February 2019
Bulk Entanglement Gravity without a Boundary: Towards Finding Einstein's Equation in Hilbert Space text January 2017
Quantum-first gravity text January 2018

Similar Records

Towards space from Hilbert space: finding lattice structure in finite-dimensional quantum systems
Journal Article · Tue Dec 04 00:00:00 EST 2018 · Quantum Studies: Mathematics and Foundations · OSTI ID:1598796

Bulk entanglement gravity without a boundary: Towards finding Einstein’s equation in Hilbert space
Journal Article · Tue Apr 03 00:00:00 EDT 2018 · Physical Review. D. · OSTI ID:1598796

Branches of the black hole wave function need not contain firewalls
Journal Article · Fri Jun 01 00:00:00 EDT 2018 · Physical Review. D. · OSTI ID:1598796