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BY-NC-ND 3.0 license Open Access Published by De Gruyter Open Access December 3, 2011

De Sitter spacetime as a momentum measuring apparatus

Nistor Nicolaevici
From the journal Open Physics


We discuss the evolution of a quantum wave packet in the expanding de Sitter spacetime using the plane wave solutions of the Dirac equation. We concentrate on the case of large negative times when the packet approaches the event horizon and confirm that the evolution accords with that expected from the classical trajectories. We point out that in certain conditions the packet can split into two components that become localized at different parts of the horizon and that this effect can be seen, in an idealized sense, as a measuring process for the momentum of the particle, in direct analogy with the measurement of spin in a Stern-Gerlach experiment.

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Published Online: 2011-12-3
Published in Print: 2012-2-1

© 2011 Versita Warsaw

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

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