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arXiv · hep-th/9701130

On the Ground State of Quantum Gravity

S. Cacciatori·G. Preparata·S. Rovelli·I. Spagnolatti·She-Sheng Xue
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Abstract

In order to gain insight into the possible Ground State of Quantized Einstein's Gravity, we have devised a variational calculation of the energy of the quantum gravitational field in an open space, as measured by an asymptotic observer living in an asymptotically flat space-time. We find that for Quantum Gravity (QG) it is energetically favourable to perform its quantum fluctuations not upon flat space-time but around a ``gas'' of wormholes, whose size is the Planck length $a_p$ ($a_p\simeq 10^{-33}$cm). As a result, assuming such configuration to be a good approximation to the true Ground State of Quantum Gravity, space-time, the arena of physical reality, turns out to be well described by Wheeler's Quantum Foam and adequately modeled by a space-time lattice with lattice constant $a_p$, the Planck lattice.

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S. Cacciatori, G. Preparata, S. Rovelli, I. Spagnolatti, She-Sheng Xue. 1998-04-13. On the Ground State of Quantum Gravity. https://doi.org/10.1016/s0370-2693(98)00349-9

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