Datensatz

Zusammenfassung

In this work, our prime objective is to study non-locality and long-range
effect of two-body correlation using quantum entanglement from the various
information-theoretic measure in the static patch of De Sitter space using a
two-body Open Quantum System (OQS). The OQS is described by two entangled atoms
which are surrounded by a thermal bath, which is modelled by a massless probe
scalar field. Firstly, we partially trace over the bath field and construct the
Gorini Kossakowski Sudarshan Lindblad (GSKL) master equation, which describes
the time evolution of the reduced subsystem density matrix. This GSKL master
equation is characterized by two components, these are-Spin chain interaction
Hamiltonian and the Lindbladian. To fix the form of both of them, using
Schwinger-Keldysh formalism we compute the Wightman functions for probe
massless scalar field. Using this result along with the large time equilibrium
behaviour we obtain the analytical solution for reduced density matrix. Further
using this solution we compute Von-Neumann entropy, R$e'$nyi entropy,
logarithmic negativity, entanglement of formation, concurrence and quantum
discord in a static patch of De Sitter space. Finally, we have studied the
violation of Bell-CHSH inequality, which is the key ingredient to study
non-locality in primordial cosmology.