Bell inequalities violation within non-Bunch-Davies states

Understand

We study the quantum nature of non-Bunch-Davies states in de Sitter space by evaluating CHSH inequality on a localized two-atom system.

• We show that quantum nonlocality can be generated through the Markovian evolution of two-atom, witnessed by a violation of CHSH inequality on its final equilibrium state.
• We find that the upper bound of inequality violation is determined by different choices of de Sitter-invariant vacua sectors.
• In particular, with growing Gibbons-Hawking temperature, the CHSH bound degrades monotonously for Bunch-Davies vacuum sector.