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arXiv · 1506.07588

Geometrogenesis under Quantum Graphity: problems with the ripening Universe

Samuel A. Wilkinson·Andrew D. Greentree
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Abstract

Quantum Graphity (QG) is a model of emergent geometry in which space is represented by a dynamical graph. The graph evolves under the action of a Hamiltonian from a high-energy pre-geometric state to a low-energy state in which geometry emerges as a coarse-grained effective property of space. Here we show the results of numerical modelling of the evolution of the QG Hamiltonian, a process we term "ripening" by analogy with crystallographic growth. We find that the model as originally presented favours a graph composed of small disjoint subgraphs. Such a disconnected space is a poor representation of our universe. A new term is introduced to the original QG Hamiltonian, which we call the hypervalence term. It is shown that the inclusion of a hypervalence term causes a connected lattice-like graph to be favoured over small isolated subgraphs.

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Samuel A. Wilkinson, Andrew D. Greentree. 2015-06-25. Geometrogenesis under Quantum Graphity: problems with the ripening Universe. https://doi.org/10.1103/physrevd.92.084007

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