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Quantum time machine

Pedro F. Gonzalez-Diaz
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Abstract

The continuation of Misner space into the Euclidean region is seen to imply the topological restriction that the period of the closed spatial direction becomes time-dependent. This restriction results in a modified Lorentzian Misner space in which the renormalized stress-energy tensor for quantized complex massless scalar fields becomes regular everywhere, even on the chronology horizon. A quantum-mechanically stable time machine with just the sub-microscopic size may then be constructed out of the modified Misner space, for which the semiclassical Hawking's chronology protection conjecture is no longer an obstruction.

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Pedro F. Gonzalez-Diaz. 1997-12-06. Quantum time machine. https://doi.org/10.1103/physrevd.58.124011

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