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Background independence in a nutshell

Carlo Rovelli·Daniele Colosi·Luisa Doplicher·Winston Fairbairn·Leonardo Modesto·Karim Noui
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Abstract

We study how physical information can be extracted from a background independent quantum system. We use an extremely simple `minimalist' system that models a finite region of 3d euclidean quantum spacetime with a single equilateral tetrahedron. We show that the physical information can be expressed as a boundary amplitude. We illustrate how the notions of "evolution" in a boundary proper-time and "vacuum" can be extracted from the background independent dynamics.

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Carlo Rovelli, Daniele Colosi, Luisa Doplicher, Winston Fairbairn, Leonardo Modesto, Karim Noui. 2004-08-24. Background independence in a nutshell. https://doi.org/10.1088/0264-9381%2F22%2F14%2F008

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