Observational constraints on quantum decoherence during inflation

• URL: http://arxiv.org/abs/1801.09949v3
• Date: Wed, 09 Oct 2024 10:57:38 GMT
• Title: Observational constraints on quantum decoherence during inflation
• Authors: Jerome Martin, Vincent Vennin,
• Abstract summary: We show that decoherence can occur without altering the power spectrum. This demonstrates that decoherence is not only of theoretical importance but can also be crucial for astrophysical observations.
• Score: 0.0
• License:
• Abstract: Since inflationary perturbations must generically couple to all degrees of freedom present in the early Universe, it is more realistic to view these fluctuations as an open quantum system interacting with an environment. Then, on very general grounds, their evolution can be modelled with a Lindblad equation. This modified evolution leads to quantum decoherence of the system, as well as to corrections to observables such as the power spectrum of curvature fluctuations. On one hand, current cosmological observations constrain the properties of possible environments and place upper bounds on the interaction strengths. On the other hand, imposing that decoherence completes by the end of inflation implies lower bounds on the interaction strengths. Therefore, the question arises of whether successful decoherence can occur without altering the power spectrum. In this paper, we systematically identify all scenarios in which this is possible. As an illustration, we discuss the case in which the environment consists of a heavy test scalar field. We show that this realises the very peculiar configuration where the correction to the power spectrum is quasi scale invariant. In that case, the presence of the environment improves the fit to the data for some inflationary models but deteriorates it for others. This clearly demonstrates that decoherence is not only of theoretical importance but can also be crucial for astrophysical observations.

Related papers

• Interacting Dirac fields in an expanding universe: dynamical condensates and particle production [41.94295877935867]
  This work focuses on a self-interacting field theory of Dirac fermions in an expanding Friedmann-Robertson-Walker universe. We study how the non-trivialative condensates arise and, more importantly, how their real-time evolution has an impact on particle production.
  arXiv  Detail & Related papers  (2024-08-12T14:21:25Z)
• The effect of quantum decoherence on inflationary gravitational waves [0.0]
  Theory of inflation provides mechanism to explain structures we observe today in the Universe, starting from quantum-mechanically generated fluctuations. During inflation, tensor perturbations interact (at least gravitationally) with other fields, meaning that we need to view these perturbations as an open system that interacts with an environment. We show that this quantum decoherence leads to a scale-dependent increase of the gravitational wave power spectrum, depending on the strength and time dependence of the interaction between the system and the environment.
  arXiv  Detail & Related papers  (2024-08-05T15:39:51Z)
• Entropy production due to spacetime fluctuations [0.0]
  We consider a non-relativistic quantum system interacting with gravitational waves. We employ the consistent histories approach to quantum mechanics to define a fluctuation relation for this system. As a result, thermodynamic entropy must be produced in the system due to its unavoidable interaction with the quantum fluctuations of spacetime.
  arXiv  Detail & Related papers  (2024-07-30T20:52:32Z)
• Non-equilibrium quantum probing through linear response [41.94295877935867]
  We study the system's response to unitary perturbations, as well as non-unitary perturbations, affecting the properties of the environment. We show that linear response, combined with a quantum probing approach, can effectively provide valuable quantitative information about the perturbation and characteristics of the environment.
  arXiv  Detail & Related papers  (2023-06-14T13:31:23Z)
• High-dimensional monitoring and the emergence of realism via multiple observers [41.94295877935867]
  Correlation is the basic mechanism of every measurement model. We introduce a model that interpolates between weak and strong non-selective measurements for qudits.
  arXiv  Detail & Related papers  (2023-05-13T13:42:19Z)
• Cosmic decoherence: primordial power spectra and non-Gaussianities [0.0]
  We study the effect of quantum decoherence on the inflationary cosmological perturbations. This process might imprint specific observational signatures revealing the quantum nature of the inflationary mechanism.
  arXiv  Detail & Related papers  (2022-11-14T18:24:52Z)
• Formation of robust bound states of interacting microwave photons [148.37607455646454]
  One of the hallmarks of interacting systems is the formation of multi-particle bound states. We develop a high fidelity parameterizable fSim gate that implements the periodic quantum circuit of the spin-1/2 XXZ model. By placing microwave photons in adjacent qubit sites, we study the propagation of these excitations and observe their bound nature for up to 5 photons.
  arXiv  Detail & Related papers  (2022-06-10T17:52:29Z)
• Discord and Decoherence [0.0]
  We investigate how quantum discord is modified by a quantum-to-classical transition. We find that the evolution of quantum discord in presence of an environment is a competition between the growth of the squeezing amplitude and the decrease of the state purity.
  arXiv  Detail & Related papers  (2021-12-09T17:01:54Z)
• No intrinsic decoherence of inflationary cosmological perturbations [0.0]
  We focus on the study of quantum decoherence of cosmological perturbations in inflationary universe. The question is, does its quantum perturbations decohere with an inflationary expansion of the universe.
  arXiv  Detail & Related papers  (2021-12-08T03:28:13Z)
• Observers of quantum systems cannot agree to disagree [55.41644538483948]
  We ask whether agreement between observers can serve as a physical principle that must hold for any theory of the world. We construct examples of (postquantum) no-signaling boxes where observers can agree to disagree.
  arXiv  Detail & Related papers  (2021-02-17T19:00:04Z)
• Emergence of classical behavior in the early universe [68.8204255655161]
  Three notions are often assumed to be essentially equivalent, representing different facets of the same phenomenon. We analyze them in general Friedmann-Lemaitre- Robertson-Walker space-times through the lens of geometric structures on the classical phase space. The analysis shows that: (i) inflation does not play an essential role; classical behavior can emerge much more generally; (ii) the three notions are conceptually distinct; classicality can emerge in one sense but not in another.
  arXiv  Detail & Related papers  (2020-04-22T16:38:25Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.