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The Unbearable Indefiniteness of Spacetime
Enrico Cinti1,2, Cristian Mariani3, Marco Sanchioni4
1Department of Philosophy, University of Geneva, 5, Rue de Candolle, CH-1211 Gèneve 4, Geneva, Switzerland.
Foundations of Physics
|February 11, 2025
Summary
We propose that spatiotemporal properties in quantum gravity (QG) are ontologically indeterminate, offering a new perspective on fundamental physics. This challenges the view that spacetime is not fundamental in quantum gravity theories.
Area of Science:
- Physics
- Quantum Gravity
- Philosophy of Science
Background:
- Spatiotemporal properties in quantum gravity (QG) are described by non-commuting operators in String Theory and Loop QG.
- Current debates often overlook the interpretation of these properties as ontologically indeterminate.
Purpose of the Study:
- To explore the implications of ontological indeterminacy for spatiotemporal properties in QG.
- To offer an alternative to the view that spacetime is not fundamental in QG.
Main Methods:
- Drawing analogies with non-relativistic quantum mechanics.
- Analyzing the role of non-commuting operators in describing observables.
Main Results:
- Physical quantities corresponding to spatiotemporal observables may be ontologically indeterminate.
- This interpretation offers a clearer understanding of QG features continuity with quantum mechanics.
- It opens new questions regarding the Eigenstate-Eigenvalue link in QG.
Conclusions:
- The concept of ontological indeterminacy extends beyond non-relativistic quantum mechanics.
- Spacetime in QG can be considered indeterminate yet fundamental, challenging prevailing views.
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