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arXiv · 0708.1825

Events and observables in generally invariant spacetime theories

Hans Westman·Sebastiano Sonego
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Abstract

We address the problem of observables in generally invariant spacetime theories such as Einstein's general relativity. Using the refined notion of an event as a ``point-coincidence'' between scalar fields that completely characterise a spacetime model, we propose a generalisation of the relational local observables that does not require the existence of four everywhere invertible scalar fields. The collection of all point-coincidences forms in generic situations a four-dimensional manifold, that is naturally identified with the physical spacetime.

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Hans Westman, Sebastiano Sonego. 2009-06-30. Events and observables in generally invariant spacetime theories. https://doi.org/10.1007/s10701-008-9235-z

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