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arXiv · 1811.00575

Interacting fermions in an expanding spacetime

L. N. Machado·H. A. S. Costa·I. G. da Paz·M. Sampaio·Jonas B. Araujo
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Abstract

We evaluate the effect of quantum electrodynamics on the correlations between Dirac field modes corresponding electron-positron pairs of opposite momenta generated by expansion of an asymptotically flat Friedmann-Robertson-Walker (FRW) universe. The mutual information of out-going electron-positron pairs is evaluated to leading order in the coupling strength and compared with the free case. It is shown a decrease in the mutual information between the electron and positron. In addition, it is found that the change in the electron-positron mutual information depends on how the momentum is distributed between the positron and photon modes.

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L. N. Machado, H. A. S. Costa, I. G. da Paz, M. Sampaio, Jonas B. Araujo. 2018-12-14. Interacting fermions in an expanding spacetime. https://doi.org/10.1103/physrevd.98.125009

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