DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Quantum mereology: Factorizing Hilbert space into subsystems with quasiclassical dynamics

Abstract

We study the question of how to decompose Hilbert space into a preferred tensor-product factorization without any preexisting structure other than a Hamiltonian operator, in particular the case of a bipartite decomposition into “system” and “environment.” Such a decomposition can be defined by looking for subsystems that exhibit quasiclassical behavior. The correct decomposition is one in which pointer states of the system are relatively robust against environmental monitoring (their entanglement with the environment does not continually and dramatically increase) and remain localized around approximately classical trajectories. We present an in-principle algorithm for finding such a decomposition by minimizing a combination of entanglement growth and internal spreading of the system. Both of these properties are related to locality in different ways. Furthermore, this formalism is relevant to questions in the foundations of quantum mechanics and the emergence of spacetime from quantum entanglement.

Authors:
 [1]; ORCiD logo [1]
  1. California Institute of Technology (CalTech), Pasadena, CA (United States)
Publication Date:
Research Org.:
California Institute of Technology (CalTech), Pasadena, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP)
OSTI Identifier:
1833823
Grant/Contract Number:  
SC0011632
Resource Type:
Accepted Manuscript
Journal Name:
Physical Review A
Additional Journal Information:
Journal Volume: 103; Journal Issue: 2; Journal ID: ISSN 2469-9926
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; Open quantum systems & decoherence; Quantum entanglement; Quantum formalism; Quantum foundations; Quantum theory; Quantum-to-classical transition

Citation Formats

Carroll, Sean M., and Singh, Ashmeet. Quantum mereology: Factorizing Hilbert space into subsystems with quasiclassical dynamics. United States: N. p., 2021. Web. doi:10.1103/physreva.103.022213.
Carroll, Sean M., & Singh, Ashmeet. Quantum mereology: Factorizing Hilbert space into subsystems with quasiclassical dynamics. United States. https://doi.org/10.1103/physreva.103.022213
Carroll, Sean M., and Singh, Ashmeet. Tue . "Quantum mereology: Factorizing Hilbert space into subsystems with quasiclassical dynamics". United States. https://doi.org/10.1103/physreva.103.022213. https://www.osti.gov/servlets/purl/1833823.
@article{osti_1833823,
title = {Quantum mereology: Factorizing Hilbert space into subsystems with quasiclassical dynamics},
author = {Carroll, Sean M. and Singh, Ashmeet},
abstractNote = {We study the question of how to decompose Hilbert space into a preferred tensor-product factorization without any preexisting structure other than a Hamiltonian operator, in particular the case of a bipartite decomposition into “system” and “environment.” Such a decomposition can be defined by looking for subsystems that exhibit quasiclassical behavior. The correct decomposition is one in which pointer states of the system are relatively robust against environmental monitoring (their entanglement with the environment does not continually and dramatically increase) and remain localized around approximately classical trajectories. We present an in-principle algorithm for finding such a decomposition by minimizing a combination of entanglement growth and internal spreading of the system. Both of these properties are related to locality in different ways. Furthermore, this formalism is relevant to questions in the foundations of quantum mechanics and the emergence of spacetime from quantum entanglement.},
doi = {10.1103/physreva.103.022213},
journal = {Physical Review A},
number = 2,
volume = 103,
place = {United States},
year = {Tue Feb 16 00:00:00 EST 2021},
month = {Tue Feb 16 00:00:00 EST 2021}
}

Works referenced in this record:

The emergence of classical properties through interaction with the environment
journal, June 1985

  • Joos, E.; Zeh, H. D.
  • Zeitschrift für Physik B Condensed Matter, Vol. 59, Issue 2
  • DOI: 10.1007/BF01725541

Uncertainty relation and non-dispersive states in finite quantum mechanics
journal, October 1997


Virtual Quantum Subsystems
journal, July 2001


Pointer basis of quantum apparatus: Into what mixture does the wave packet collapse?
journal, September 1981


Quantum Tensor Product Structures are Observable Induced
journal, February 2004


Glimmers of a Pre-geometric Perspective
journal, December 2009


Hilbert space structure in quantum gravity: an algebraic perspective
journal, December 2015


Quantum state reduction: Generalized bipartitions from algebras of observables
journal, March 2020


The stretched horizon and black hole complementarity
journal, October 1993


The rise and fall of redundancy in decoherence and quantum Darwinism
journal, August 2012


The world as a hologram
journal, November 1995

  • Susskind, Leonard
  • Journal of Mathematical Physics, Vol. 36, Issue 11
  • DOI: 10.1063/1.531249

Atom lasers, coherent states, and coherence. I. Physically realizable ensembles of pure states
journal, March 2002


Finite-dimensional quantum mechanics of a particle. II
journal, May 1982

  • Jagannathan, R.; Santhanam, T. S.
  • International Journal of Theoretical Physics, Vol. 21, Issue 5
  • DOI: 10.1007/BF02650236

The Large-N Limit of Superconformal Field Theories and Supergravity
journal, January 1999

  • Maldacena, Juan
  • International Journal of Theoretical Physics, Vol. 38, Issue 4, p. 1113-1133
  • DOI: 10.1023/A:1026654312961

The Ryu–Takayanagi Formula from Quantum Error Correction
journal, May 2017


Classical World Arising out of Quantum Physics under the Restriction of Coarse-Grained Measurements
journal, November 2007


Consistent histories and the interpretation of quantum mechanics
journal, July 1984

  • Griffiths, Robert B.
  • Journal of Statistical Physics, Vol. 36, Issue 1-2
  • DOI: 10.1007/BF01015734

A general theoretical framework for decoherence in open and closed systems
journal, July 2008


Preferred States, Predictability, Classicality and the Environment-Induced Decoherence
journal, February 1993


Consciousness as a state of matter
journal, July 2015


Decoherence: A Closed-System Approach
journal, August 2013

  • Fortin, Sebastian; Lombardi, Olimpia; Castagnino, Mario
  • Brazilian Journal of Physics, Vol. 44, Issue 1
  • DOI: 10.1007/s13538-013-0151-0

"Relative State" Formulation of Quantum Mechanics
journal, July 1957


Quantum Histories
journal, January 1998


Environment-induced decoherence, classicality, and consistency of quantum histories
journal, September 1993


Locality from the Spectrum
journal, February 2019

  • Cotler, Jordan S.; Penington, Geoffrey R.; Ranard, Daniel H.
  • Communications in Mathematical Physics, Vol. 368, Issue 3
  • DOI: 10.1007/s00220-019-03376-w

Unitary Operator Bases
journal, April 1960

  • Schwinger, J.
  • Proceedings of the National Academy of Sciences, Vol. 46, Issue 4
  • DOI: 10.1073/pnas.46.4.570

The Hilbert space of quantum gravity is locally finite-dimensional
journal, October 2017

  • Bao, Ning; Carroll, Sean M.; Singh, Ashmeet
  • International Journal of Modern Physics D, Vol. 26, Issue 12
  • DOI: 10.1142/S0218271817430131

Self-induced decoherence: a new approach
journal, March 2004

  • Castagnino, Mario; Lombardi, Olimpia
  • Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics, Vol. 35, Issue 1
  • DOI: 10.1016/j.shpsb.2003.03.001

Quantum-optical Phase and Canonical Conjugation
journal, November 1990

  • Pegg, D. T.; Vaccaro, J. A.; Barnett, Stephen M.
  • Journal of Modern Optics, Vol. 37, Issue 11
  • DOI: 10.1080/09500349014551931

Classical dynamics of the quantum harmonic chain
journal, November 1999


On the consistent histories approach to quantum mechanics
journal, March 1996

  • Dowker, Fay; Kent, Adrian
  • Journal of Statistical Physics, Vol. 82, Issue 5-6
  • DOI: 10.1007/BF02183396

Quantum mechanics in finite dimensions
journal, October 1976

  • Santhanam, T. S.; Tekumalla, A. R.
  • Foundations of Physics, Vol. 6, Issue 5
  • DOI: 10.1007/BF00715110

Bulk entanglement gravity without a boundary: Towards finding Einstein’s equation in Hilbert space
journal, April 2018


Space from Hilbert space: Recovering geometry from bulk entanglement
journal, January 2017


Consciousness as a State of Matter
text, January 2014


Classical Dynamics of the Quantum Harmonic Chain
text, January 1999