Indirect detection of Cosmological Constant from interacting open quantum system

Abstract

In this letter, we study the indirect detection of {\it Cosmological Constant} from an {\it open quantum system} of $N$ entangled spins, weakly interacting with a thermal bath, a massless scalar field minimally coupled with the static De Sitter background, by computing the spectroscopic shifts. By assuming pairwise entanglement between spins, we construct entangled $N$ states using a generalisation of the superposition principle. We have found that in the realistic large $N$ limit, where the system consists of $N\sim{\cal O}(10^3-10^4)$ spins, the corresponding spectroscopic shifts, caused by the effective Hamiltonian of the system due to Casimir Polder interaction with the bath, play a crucial role to determine the observationally consistent Cosmological Constant, $\Lambda\sim {\cal O}(10^{-122})$ (Planckian units) in the static patch of De Sitter space.