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arXiv · 2103.00198

Matter-driven change of spacetime topology

J. Ambjørn·Z. Drogosz·J. Gizbert-Studnicki·A. Görlich·J. Jurkiewicz·D. Németh
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Abstract

Using Monte-Carlo computer simulations, we study the impact of matter fields on the geometry of a typical quantum universe in the CDT model of lattice quantum gravity. The quantum universe has the size of a few Planck lengths and the spatial topology of a three-torus. The matter fields are multi-component scalar fields taking values in a torus with circumference $δ$ in each spatial direction, which acts as a new parameter in the CDT model. Changing $δ$, we observe a phase transition caused by the scalar field. This discovery may have important consequences for quantum universes with non-trivial topology, since the phase transition can change the topology to a simply connected one.

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J. Ambjørn, Z. Drogosz, J. Gizbert-Studnicki, A. Görlich, J. Jurkiewicz, D. Németh. 2021-09-14. Matter-driven change of spacetime topology. https://doi.org/10.1103/physrevlett.127.161301

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