General covariance and the objectivity of space-time point-events
arXiv:gr-qc/0503069
Abstract
"The last remnant of physical objectivity of space-time" is disclosed, beyond the Leibniz equivalence, in the case of a continuous family of spatially non-compact models of general relativity. The {\it physical individuation} of point-events is furnished by the intrinsic degrees of freedom of the gravitational field, (viz, the {\it Dirac observables}) that represent - as it were - the {\it ontic} part of the metric field. The physical role of the {\it epistemic} part (viz. the {\it gauge} variables) is likewise clarified. At the end, a peculiar four-dimensional {\it holistic and structuralist} view of space-time emerges which includes elements common to the tradition of both {\it substantivalism} and {\it relationism}. The observables of our models undergo real {\it temporal change} and thereby provide a counter-example to the thesis of the {\it frozen-time} picture of evolution. Invited Contribution to the ESF 2004 Oxford Conference on Space-Time
arXiv commentrevtex, 23 pages
References in corpus (7)
- The Dynamics of General Relativity
- The Gravitational Hamiltonian, Action, Entropy, and Surface Terms
- Partial observables
- Canonical Quantum Gravity
- The Rest-Frame Instant Form of Metric Gravity
- Fibered Manifolds, Natural Bundles, Structured Sets, G-Sets and all that: The Hole Story from Space Time to Elementary Particles
- Ephemeral point-events: is there a last remnant of physical objectivity?