The case for background independence

By Lee Smolin. 2005

217 citations recorded by the source corpus.

The aim of this paper is to explain carefully the arguments behind the assertion that the correct quantum theory of gravity must be background independent. We begin by recounting how the debate overwhetherquantum 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. Some first attempts to cast string/M theory into a background independent formulation are also mentioned. 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 recent issues concerning the string theory landscape are reviewed and it is argued that they can only be resolved within the context of a background independent formulation. Finally, we review some recent proposals to make quantum theory more relational.

Subfields: Atomic and Molecular Physics, and Optics, Nuclear and High Energy Physics, Statistical and Nonlinear Physics

View Paper: https://www.semanticscholar.org/paper/f6bb1c7bf37b199fbc7dbdbd786c1178678055b6

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Atomic and Molecular Physics, and Optics

1. R. Loll
2. C. Isham
3. A. Doering
4. J. Jurkiewicz
5. C. Isham
6. Andreas C. Döring

In Nuclear and High Energy Physics

1. R. Loll
2. J. Jurkiewicz
3. C. Isham
4. A. Doering
5. C. Isham
6. Andreas C. Döring
7. J. Ambjrn
8. Gianluca Calcagni

In Statistical and Nonlinear Physics

1. R. Loll
2. J. Jurkiewicz
3. J. Ambjrn
4. C. Isham
5. A. Doering
6. C. Isham
7. Andreas C. Döring
8. M. Niedermaier

Citations in the corpus

• A topos foundation for theories of physics: I. Formal languages for physics (2007, background): “In fact, most modern approaches to quantum gravity aspire to a formalism that is background independent [28, 29, 30, 31].”
• The universe from scratch (2005, background): “Decades of quantum gravity research, including numerous trials and errors, have convinced many of the necessity of background-independence and a nonperturbative quantization approach [ 10 ], and the last twenty years or so have seen intense efforts to develop alternative ways of quantizing applicabl”
• “What is a Thing?”: Topos Theory in the Foundations of Physics (2008, background): “In fact, most modern approaches to quantum gravity aspire to a formalism that is background independent [4, 15, 67, 68].”