Discord and Decoherence

Martin, Jerome; Micheli, Amaury; Vennin, Vincent

doi:10.48550/arxiv.2112.05037

Cited by 4 publications

(4 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…to effectively decohere cosmological perturbations, but it suggests that decoherence in the early universe may not be as ubiquitous as common wisdom suggests. This is crucial to determine whether or not genuine quantum signals can be detected in cosmological structures [18,22,25,43,44,101,138,139]. Natural prospects of our work include the investigation of models with sharp turns [66,96], the impact of multiple entropic directions [71] on the emergence of Markovianity [137], as well as non-linear interactions [72,140,141].…”

Section: Quantum Recoherencementioning

confidence: 99%

Quantum recoherence in the early universe

Colas

Grain

Vennin

2023

EPL

View full text Add to dashboard Cite

Despite being created through a fundamentally quantum-mechanical process, cosmological structures have not yet revealed any sign of genuine quantum correlations. Among the obstructions to the direct detection of quantum signatures in cosmology, environmental-induced decoherence is arguably one of the most inevitable. Yet, we discover a mechanism of quantum recoherence for the adiabatic perturbations when they couple to an entropic sector. After a transient phase of decoherence, a turning point is reached, recoherence proceeds and adiabatic perturbations exhibit a large amount of self-coherence at late-time. This result is also understood by means of a non-Markovian master equation, which reduces to Wilsonian effective-field theory in the unitary limit. This allows us to critically assess the validity of open-quantum-system methods in cosmology and to highlight that re(de)coherence from linear interactions has no flat-space analogue.

show abstract

Section: Quantum Recoherencementioning

confidence: 99%

Quantum recoherence in the early universe

Colas

Grain

Vennin

2023

EPL

View full text Add to dashboard Cite

show abstract

“…• The direct connection between the higher point quantum correlations with the all of these possible quantum information theoretic measures, imprints of quantum entanglement in quantum correlations computed in the quantum field theory of de Sitter space and the primordial cosmological set ups are another interesting possibilities which one can study in future from the present set up that we have constructed in this paper. • Extending the present computation to study role quantum mechanical decoherence [25,26,29,126,127] and quantum diffusion [128] might be very useful for the future study which can explain various unknown facts from the present set up in global as well as in the planer patch of de Sitter space. • The construction of squeezed quantum mechanical states and its consequences is a common area of research in cosmological set up.…”

Section: Discussionmentioning

confidence: 96%

Entanglement Negativity in de Sitter Biverse from Stringy Axionic Bell Pair: An Analysis Using Bunch‐Davies Vacuum

Choudhury

2023

Fortschritte der Physik

View full text Add to dashboard Cite

In this work, signatures of quantum entanglement by computing entanglement negativity between two causally unrelated regions in 3 + 1 dimensional global de Sitter space are studied. A bipartite quantum field theoretic setup for this purpose, driven by an axionic Bell pair resulting from Type IIB string compactification on a Calabi‐Yau three fold is investigated. A spherical surface that divides the spatial slice of the global de Sitter space into exterior and interior causally unrelated sub regions is taken into account. For the computational purpose, the simplest possible initial choice of quantum vacuum, which is Bunch‐Davies state is used. The quantitative quantum information theoretic measure for entanglement negativity turns out be consistent with the results obtained for entanglement entropy, even it is better than that from quantum information theoretic point of view. The problem in a hyperbolic open chart where one of the causally unrelated observers remains constrained and the scale dependence enters to the corresponding quantum information theoretic entanglement measure for axionic Bell pair is designed. From the analysis it is found that in the large scales, initially maximally entangled Bunch‐Davies state turns out to be strongly entangled or weakly entangled depending on the axionic decay constant and the supersymmetry breaking scale. It is also found that at the small scales the initial entanglement can be perfectly recovered. The possibility of having a biverse picture, which is a mini version of the multiverse in the present theoretical set up is discussed. Last but not the least, the necessary criteria for generating non vanishing quantum entanglement measures within the framework of quantum field theory of global de Sitter space as well as well as in primordial cosmology due to the axion derived from string theory are provided.

show abstract

“…These states are also now being used in gravitational wave physics [17][18][19] to enhance the sensitivity of gravitational wave detectors [20][21][22][23], such as the LIGO [24] and to improve measurement techniques in quantum metrology [25][26][27][28][29][30][31]. For a more broad class of application of squeezed states see [32][33][34][35][36][37][38][39][40][41][42][43][44].…”

Section: Introductionmentioning

confidence: 99%

Four-mode squeezed states in de Sitter space: A study with two field interacting quantum system

Choudhury¹,

Panda²,

Pandey³

et al. 2022

Preprint

View full text Add to dashboard Cite

In this paper we study the application of four-mode squeezed states in the cosmological context, studying two weakly coupled scalar fields in the planar patch of the de Sitter space. We construct the four-mode squeezed state formalism and connect this concept with the Hamiltonian of the two coupled inverted harmonic oscillators having a time-dependent effective frequency in the planar patch of the de Sitter space. Further, the corresponding evolution operator for the quantum Euclidean vacuum state has been constructed, which captures its dynamics. Using the Heisenberg picture coupled differential equations describing the time evolution for all squeezing parameters (amplitude, phase and angle) have been obtained, for the weakly coupled two scalar field model. With the help of these evolutions for the coupled system, we simulate the dynamics of the squeezing parameters in terms of conformal time. From our analysis, we observe interesting dynamics, which helps us to explore various underlying physical implications of the weakly coupled two scalar field system in the planar patch of the de Sitter cosmological background.

show abstract

Discord and Decoherence

Cited by 4 publications

References 45 publications

Quantum recoherence in the early universe

Quantum recoherence in the early universe

Entanglement Negativity in de Sitter Biverse from Stringy Axionic Bell Pair: An Analysis Using Bunch‐Davies Vacuum

Four-mode squeezed states in de Sitter space: A study with two field interacting quantum system

Contact Info

Product

Resources

About