# Large scale quantum entanglement in de Sitter spacetime

@article{Matsumura2017LargeSQ, title={Large scale quantum entanglement in de Sitter spacetime}, author={Akira Matsumura and Yasusada Nambu}, journal={Physical Review D}, year={2017} }

We investigate quantum entanglement between two symmetric spatial regions in de Sitter space with the Bunch-Davies vacuum. As a discretized model of the scalar field for numerical simulation, we consider a harmonic chain model. Using the coarse-grained variables for the scalar field, it is shown that the multipartite entanglement on the superhorizon scale exists by checking the monogamy relation for the negativity which quantifies the entanglement between the two regions. Further, we consider…

## 14 Citations

### Entanglement dynamics in de Sitter spacetime

- Physics
- 2017

We apply a master equation approximation with dynamical coarse graining to a pair of detectors interacting with a scalar field. By solving the master equation numerically, we investigate the…

### Generation of genuine tripartite entanglement for continuous variables in de Sitter space

- PhysicsPhysics Letters B
- 2020

### Harvesting Large Scale Entanglement in de Sitter Space with Multiple Detectors

- PhysicsEntropy
- 2017

It is found that it is possible to access to the entanglement on the super horizon scale if a sufficiently large number of detectors are prepared.

### Vacuum state in de Sitter spacetime with static charts

- PhysicsPhysical Review D
- 2018

We study the free massive scalar field in de Sitter spacetime with static charts. In particular, we find positive-frequency modes for the Bunch-Davies vacuum state natural to the static charts as…

### Late-time quantum radiation by a uniformly accelerated detector in de Sitter spacetime

- PhysicsPhysical Review D
- 2018

We investigate the quantum radiation emitted by a uniformly accelerated Unruh-DeWitt detector in de Sitter spacetime. We find that there exists a non-vanishing quantum radiation at late times in the…

### Distribution and Generation of Quantum Coherence for Gaussian States in de Sitter Space

- PhysicsAnnalen der Physik
- 2021

The distribution and generation of quantum coherence for two‐mode and multi‐mode Gaussian states in de Sitter space are studied. It is found that the quantum coherence is redistributed among the mode…

### Squeezing of Primordial Gravitational Waves as Quantum Discord

- PhysicsUniverse
- 2020

We investigate the squeezing of primordial gravitational waves (PGWs) in terms of quantum discord. We construct a classical state of PGWs without quantum discord and compare it with the Bunch–Davies…

### QMetrology from QCosmology: Study with entangled two qubit open quantum system in De Sitter space

- Physics
- 2020

In this paper, our prime objective is to apply the techniques of {\it parameter estimation theory} and the concept of {\it Quantum Metrology} in the form of {\it Fisher Information} to investigate…

### Induced entanglement entropy of harmonic oscillators in non-commutative phase space

- PhysicsModern Physics Letters A
- 2019

We study the entanglement entropy of harmonic oscillators in non-commutative phase space (NCPS). We propose a new definition of quantum Rényi entropy based on Wigner functions in NCPS. Using the…

### Quantum circuit model of black hole evaporation

- PhysicsClassical and Quantum Gravity
- 2018

We consider a quantum circuit model describing the evaporation process of black holes. We specifically examine the behavior of the multipartite entanglement represented by this model, and find that…

## References

SHOWING 1-10 OF 28 REFERENCES

### Entanglement entropy in de Sitter space

- Physics
- 2013

A bstractWe compute the entanglement entropy for some quantum field theories on de Sitter space. We consider a superhorizon size spherical surface that divides the spatial slice into two regions,…

### Entanglement of Quantum Fluctuations in the Inflationary Universe

- Physics
- 2008

We investigate quantum entanglement of a scalar field in the inflationary universe. By introducing a bipartite system using a lattice model of scalar field, we apply the separability criterion based…

### Entanglement negativity in the multiverse

- Physics
- 2014

We explore quantum entanglement between two causally disconnected regions in the multiverse. We first consider a free massive scalar field, and compute the entanglement negativity between two…

### Impact of quantum entanglement on spectrum of cosmological fluctuations

- Physics
- 2014

We investigate the effect of entanglement between two causally separated open charts in de Sitter space on the spectrum of vacuum fluctuations. We consider a free massive scalar field, and construct…

### Entanglement renormalization.

- PhysicsPhysical review letters
- 2007

Numerical simulations with the ground state of a 1D lattice at criticality show that the resulting coarse-grained sites require a Hilbert space dimension that does not grow with successive RG transformations, and calculations unveil that ground state entanglement in extended quantum systems is organized in layers corresponding to different length scales.

### Critical and noncritical long-range entanglement in Klein-Gordon fields

- Physics
- 2009

We investigate the entanglement between two spatially separated intervals in the vacuum state of a free one-dimensional Klein-Gordon field by means of explicit computations in the continuum limit of…

### Classical and Quantum Correlations of Scalar Field in the Inflationary Universe

- Physics
- 2011

We investigate classical and quantum correlations of a quantum field in the inflationary universe using a particle detector model. By considering the entanglement and correlations between two…

### Entanglement and separability of quantum harmonic oscillator systems at finite temperature

- PhysicsQuantum Inf. Comput.
- 2008

It is proved that at sufficiently high temperatures the thermal state becomes fully separable and bounds on the critical temperature at which this happens are deduced, and the bound becomes tight for a wide class of Hamiltonians with sufficient translation symmetry.

### Separability for lattice systems at high temperature

- Physics
- 2005

Equilibrium states of infinite extended lattice systems at high temperature are studied with respect to their entanglement. Two notions of separability are offered. They coincide for finite systems…