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Cited by 217Noncommutative and Quantum Gravity TheoriesRelativity and Gravitational TheoryBlack Holes and Theoretical Physics

The Case for Background Independence

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Smolin, Lee·2006·The Structural Foundations of Quantum Gravity
DOI 10.1093/acprof:oso/9780199269693.003.0007
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Abstract

This chapter explains the arguments behind the assertion that the correct quantum theory of gravity must be background independent. It begins by recounting how the debate over whether quantum gravity must be background independent is a continuation of a long-standing argument in the history of physics and philosophy over whether space and time are relational or absolute. This leads to a careful statement of what physicists mean when we speak of background independence. Given this we can characterize the precise sense in which general relativity is a background-independent theory. The leading background-independent approaches to quantum gravity are then discussed, including causal set models, loop quantum gravity, and dynamical triangulations, and their main achievements are summarized along with the problems that remain open. The relational/absolute debate has implications also for other issues such as unification and how the parameters of the standard models of physics and cosmology are to be explained. The chapter reviews recent issues concerning the string theory landscape and argues that they can only be resolved within the context of a background-independent formulation. Finally, it reviews some recent proposals to make quantum theory more relational.

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  • Most causal sets sanctioned merely by the kinematic axiom do not stand in a relation of faithful approximation to spacetimes with low-dimensional manifolds.

    “It turns out that most causal sets sanctioned merely by the kinematic axiom do not stand in a relation of faithful approximation to spacetimes with low-dimensional manifolds.”

    From What Becomes of a Causal Set? (2017) · cites this paper as Smolin 2006

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Authors
Smolin, L.
Affiliations
University of Waterloo (CA)
Corresponding author
Smolin, Lee
ORCID
Smolin, Lee
Venue
The Structural Foundations of Quantum Gravity
Publisher
Oxford University Press
Published
2006-11-16
Pages
196-239
DOI
10.1093/acprof:oso/9780199269693.003.0007
OpenAlex
W1490269857
Cited by
217
References
2
Citations by year
2026: 6 · 2025: 15 · 2024: 7 · 2023: 14 · 2022: 10 · 2021: 20 · 2020: 6 · 2019: 4 · 2018: 10 · 2017: 1 · 2016: 8 · 2015: 11 · 2014: 14 · 2013: 15 · 2012: 7
FWCI
48.90
Type
book chapter
Language
en
Open access
Locations
  • Oxford University Press eBooks (publishedVersion)
  • arXiv (Cornell University) (submittedVersion)
  • CERN Document Server (European Organization for Nuclear Research) (submittedVersion)
  • arXiv (Cornell University)
Topics
  • Physical Sciences › Physics and Astronomy › Statistical and Nonlinear Physics › Noncommutative and Quantum Gravity Theories
  • Physical Sciences › Physics and Astronomy › Astronomy and Astrophysics › Relativity and Gravitational Theory
  • Physical Sciences › Physics and Astronomy › Nuclear and High Energy Physics › Black Holes and Theoretical Physics
Keywords
background independence, quantum gravity, relationalism, absolute space and time, general relativity, causal sets, loop quantum gravity, dynamical triangulations, string landscape, unification, philosophy of physics, quantum foundations

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