Entanglement of Dirac fields in an expanding spacetime

I. Fuentes, R. B. Mann, E. Martin-Martinez, S. Moradi

Published 2010-07-09, updated 2010-08-28Version 2

We study the entanglement generated between Dirac modes in a 2-dimensional conformally flat Robertson-Walker universe. We find radical qualitative differences between the bosonic and fermionic entanglement generated by the expansion. The particular way in which fermionic fields get entangled encodes more information about the underlying space-time than the bosonic case, thereby allowing us to reconstruct the parameters of the history of the expansion. This highlights the importance of bosonic/fermionic statistics to account for relativistic effects on the entanglement of quantum fields.