Universe (Aug 2022)

Analogue Non-Causal Null Curves and Chronology Protection in a dc-SQUID Array

  • Carlos Sabín

DOI
https://doi.org/10.3390/universe8090452
Journal volume & issue
Vol. 8, no. 9
p. 452

Abstract

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We propose an analogue quantum simulator of a 1 + 1D spacetime containing non-causal curves, in particular null geodesics going back in time, by means of a dc-SQUID array embedded on an open superconducting transmission line. This is achieved by mimicking the spatial dependence of the metric with the propagation speed of the electromagnetic field in the simulator, which can be modulated by an external magnetic flux. We show that it is possible to simulate a spacetime region containing non-causal null geodesics, but not a full spacetime containing a chronological horizon separating regions with non-causal null geodesics and regions without them. This is in agreement with a recent suggestion of an analogue-gravity chronology protection mechanism by Barceló et al.

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