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Related papers: Multipoint correlators in multifield cosmology

200 papers

Assuming a LCDM universe in a single-field inflationary scenario, we compute the three-point correlation function of the observed matter density fluctuation in the squeezed triangular configuration, accounting for all the relativistic…

Cosmology and Nongalactic Astrophysics · Physics 2022-08-25 Jaiyul Yoo , Nastassia Grimm , Ermis Mitsou

We introduce a well-defined and unbiased measure of the strength of correlations in quantum many-particle systems which is based on the relative von Neumann entropy computed from the density operator of correlated and uncorrelated states.…

Strongly Correlated Electrons · Physics 2015-05-30 K. Byczuk , J. Kunes , W. Hofstetter , D. Vollhardt

This is a sequel to a previous detailed study of quantum corrections to cosmological correlations. It was found there that except in special cases these corrections depend on the whole history of inflation, not just on the behavior of…

High Energy Physics - Theory · Physics 2008-11-26 Steven Weinberg

We compute correlation functions of the primordial density perturbations when they couple to a gapless, strongly coupled sector of spectator fields -- ``unparticles" -- during inflation. We first derive a four-point function of conformally…

High Energy Physics - Theory · Physics 2026-04-21 Guilherme L. Pimentel , Chen Yang

We investigate the quantumness of primordial cosmological fluctuations and its detectability. The quantum discord of inflationary perturbations is calculated for an arbitrary splitting of the system, and shown to be very large on…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-29 Jerome Martin , Vincent Vennin

The ``in-in'' formalism is reviewed and extended, and applied to the calculation of higher-order Gaussian and non-Gaussian correlations in cosmology. Previous calculations of these correlations amounted to the evaluation of tree graphs in…

High Energy Physics - Theory · Physics 2008-11-26 Steven Weinberg

We explore the adiabatic particle excitations of an interacting field in a cosmological background. By following the time-evolution of the quantum state corresponding to the particle excitation, we show how the basic properties…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Daniel Arteaga

For icosahedral inflation, we compute the tensor modes' two-point function in the presence of higher derivative corrections, and show that in general this features anisotropies that are aligned with the underlying icosahedral structure. The…

High Energy Physics - Theory · Physics 2018-07-12 Jonghee Kang , Alberto Nicolis

We review recent literature on the connection between quantum entanglement and cosmology, with an emphasis on the context of expanding universes. We discuss recent theoretical results reporting on the production of entanglement in quantum…

General Relativity and Quantum Cosmology · Physics 2015-03-20 Eduardo Martin-Martinez , Nicolas C. Menicucci

Pointlike systems coupled to quantum fields are often employed as toy models for measurements in quantum field theory. In this paper, we identify the field observables recorded by such models. We show that in models that work in the strong…

Quantum Physics · Physics 2023-08-29 Maria Papageorgiou , Jose de Ramon , Charis Anastopoulos

When energy is not conserved, imprints of new physics on observable cosmology might not follow the rules of local effective actions. By capturing dissipative and diffusive effects, open effective field theories account for the possibly…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-17 Thomas Colas

The squeezed limit of the three-point function of cosmological perturbations is a powerful discriminant of different models of the early Universe. We present a conceptually simple and complete framework to relate any primordial bispectrum…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Enrico Pajer , Fabian Schmidt , Matias Zaldarriaga

In order to extract maximal information about cosmology from the large-scale structure of the Universe, one needs to use every bit of signal that can be observed. Beyond the spatial distributions of astronomical objects, the spatial…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-23 Takahiko Matsubara

We study the power spectrum of quasi-single field inflation where strong coupling is considered. The contribution from the massive propagator can be divided into local and non-local contributions. The local one is the leading contribution…

High Energy Physics - Theory · Physics 2018-02-07 Aditya Varna Iyer , Shi Pi , Yi Wang , Ziwei Wang , Siyi Zhou

In this sequel paper we explore how macroscopic quantum phenomena can be measured or understood from the behavior of quantum correlations which exist in a quantum system of many particles or components and how the interaction strengths…

Quantum Physics · Physics 2015-05-28 C H Chou , B L Hu , Y Subasi

In the present work an inflationary tachyon field model of the early universe is considered. Several cosmological effects produced by a particular potential in this tachyonic era are studied, under the approximation of slow-roll inflation.…

General Relativity and Quantum Cosmology · Physics 2015-11-09 Iván E. Sánchez G. , Osvaldo P. Santillan

Does the observable spectrum of cosmic fluctuations depend on detailed initial conditions? This addresses the question if the general inflationary paradigm is sufficient to predict within a given model the spectrum and amplitude of cosmic…

General Relativity and Quantum Cosmology · Physics 2015-10-14 C. Wetterich

After introducing gauge-invariant cosmological perturbation theory we give an improved set of governing equations for multiple fluids including energy transfer. Having defined adiabatic and entropic perturbations we derive the…

Astrophysics · Physics 2007-05-23 Karim A. Malik

Informed by a quantum information perspective, we interpret cosmological expansion of space as growing entanglement between underlying degrees of freedom. In particular, we focus on inflationary cosmology, which, while being a successful…

General Physics · Physics 2021-09-10 Ashmeet Singh , Olivier Doré

We derive exact and closed-form expressions for a large class of two-point and three-point inflation correlators with the tree-level exchange of a single massive particle. The intermediate massive particle is allowed to have arbitrary mass,…

High Energy Physics - Theory · Physics 2023-07-26 Zhehan Qin , Zhong-Zhi Xianyu