Quantum discord in de Sitter space

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We study quantum discord between two free modes of a massive scalar field in a maximally entangled state in de Sitter space.

• We introduce two observers, one in a global chart and the other in an open chart of de Sitter space, and the observers determine the quantum discord created by each detecting one of the modes.
• This situation is analogous to the relationship between an observer in a Minkowski chart and another in one of the two Rindler charts in flat space.
• We find that the state becomes less entangled as the curvature of the open chart gets larger.