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To Quantize or Not to Quantize: Fact and Folklore in Quantum Gravity

Published online by Cambridge University Press:  01 January 2022

Christian Wüthrich
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Abstract

Does the need to find a quantum theory of gravity imply that the gravitational field must be quantized? Physicists working in quantum gravity routinely assume an affirmative answer, often without being aware of the metaphysical commitments that tend to underlie this assumption. The ambition of this article is to probe these commitments and to analyze some recently adduced physical—as opposed to metaphysical—arguments pertinent to the issue of quantization. While there exist good reasons to quantize gravity, as this analysis will show, alternative approaches to gravity challenge the received wisdom. These renegade approaches do not regard gravity as a fundamental force, but rather as effective, i.e., as merely supervening on fundamental physics. I will urge that these alternative accounts at least prove the tenability of an opposition to quantization.

Type
Quantum Mechanics
Information
Philosophy of Science , Volume 72 , Issue 5: Proceedings of the 2004 Biennial Meeting of The Philosophy of Science Association. Part I: Contributed Papers , December 2005 , pp. 777 - 788
Copyright
Copyright © The Philosophy of Science Association

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Footnotes

‡

I wish to thank John Earman, Florian Girelli, John Moffat, Carlo Rovelli and Danny Terno for discussions. This work was supported by the Swiss National Science Foundation (grant PBSK1-102693).

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