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Entanglement entropy of α-vacua in de Sitter space

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We consider the entanglement entropy of a free massive scalar field in the one parameter family of α-vacua in de Sitter space by using a method developed by Maldacena and Pimentel. An α-vacuum can be thought of as a state filled with particles from the point of view of the Bunch-Davies vacuum. Of all the α-vacua we find that the entanglement entropy takes the minimal value in the Bunch-Davies solution. We also calculate the asymptotic value of the Rényi entropy and find that it increases as α increases. We argue these features stem from pair condensation within the non-trivial α-vacua where the pairs have an intrinsic quantum correlation.


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Correspondence to Sugumi Kanno.

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ArXiv ePrint: 1404.6815

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Kanno, S., Murugan, J., Shock, J.P. et al. Entanglement entropy of α-vacua in de Sitter space. J. High Energ. Phys. 2014, 72 (2014).

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  • Classical Theories of Gravity
  • Cosmology of Theories beyond the SM
  • Field Theories in Higher Dimensions