Reflections on the Spatiotemporal Aspects of the Quantum World
arXiv:quant-ph/0205058 · doi:10.1142/S0217732302007533
Abstract
The proper resolution of the so-called measurement problem requires a "top-down" conception of the quantum world that is opposed to the usual "bottom-up" conception, which builds on an intrinsically and maximally differentiated manifold. The key to that problem is that the fuzziness of a variable can manifest itself only to the extent that less fuzzy variables exist. Inasmuch as there is nothing less fuzzy than the metric, this argues against a quantum-gravity phenomenology and suggests that a quantum theory of gravity is something of a contradiction in terms - a theory that would make it possible to investigate the physics on scales that do not exist, or to study the physical consequences of a fuzziness that has no physical consequences, other than providing a natural cutoff for the quantum field theories of particle physics.
Invited talk at the First Meeting on the Interface of Gravitational and Quantum Realms held at IUCAA, Pune (India), December 17--21, 2001. To appear in Mod. Phys. Lett. A. 17 pages. LaTeX2e