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Related papers: Loop corrections in the separate universe picture

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The spatially closed Friedmann-Lema\^{i}tre-Robertson-Walker model in loop quantum cosmology admits two inequivalent consistent quantizations: one based on expressing the field strength in terms of the holonomies over closed loops, and,…

General Relativity and Quantum Cosmology · Physics 2017-04-14 John L. Dupuy , Parampreet Singh

The Higgs trilinear coupling provides a unique opportunity to study the structure of the Higgs sector and probe indirect signs of BSM Physics -- even if new states are somehow hidden. In models with extended Higgs sectors, large deviations…

High Energy Physics - Phenomenology · Physics 2020-12-11 Johannes Braathen , Shinya Kanemura

Non-perturbative quantum geometric effects in Loop Quantum Cosmology predict a $\rho^2$ modification to the Friedmann equation at high energies. The quadratic term is negative definite and can lead to generic bounces when the matter energy…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Parampreet Singh , Kevin Vandersloot , G. V. Vereshchagin

A unified multi scalar field model with three flat regions is discussed. The three flat regions are the inflation, early and late dark energy epochs. The potential is obtained by a spontaneous breaking of scale invariance generated by Non…

General Relativity and Quantum Cosmology · Physics 2022-06-22 Eduardo Guendelman , Ramon Herrera , David Benisty

We study the non-equilibrium dynamics of a system of coupled scalar fields in a Friedmann-Robertson-Walker (FRW) universe. We consider the evolution of spatially homogeneous "classical" fields and of their quantum fluctuations including the…

High Energy Physics - Phenomenology · Physics 2014-11-21 Jurgen Baacke , Laura Covi , Nina Kevlishvili

The conventional background solution for the evolution of a single canonical inflaton field performs admirably in extreme scenarios such as the slow-roll phase (where the slow-roll parameter is much less than one) and the deep reheating era…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-26 Manjeet Kaur , Debottam Nandi , Sharath Raghavan B

Accurate characterization of measurement backaction is crucial for understanding the limits of reusing quantum correlations in sequential scenarios. Here, we develop a unified quantum-instrument framework that goes beyond simple measurement…

Quantum Physics · Physics 2026-05-06 Zinuo Cai , Jianxin Song , Changliang Ren

The effective evolution of an inhomogeneous universe model in any theory of gravitation may be described in terms of spatially averaged variables. In Einstein's theory, restricting attention to scalar variables, this evolution can be…

General Relativity and Quantum Cosmology · Physics 2010-04-06 Thomas Buchert

We study the dynamics and predictions of a new emergent-universe model recently derived within Quantum Reduced Loop Gravity and based on the so-called statistical regularization scheme. These effective geometries show a dynamical transition…

General Relativity and Quantum Cosmology · Physics 2019-04-24 Javier Olmedo , Emanuele Alesci

We study the non-linear dynamics of axion inflation, capturing for the first time the inhomogeneity and full dynamical range during strong backreaction, till the end of inflation. Accounting for inhomogeneous effects leads to a number of…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-01 Daniel G. Figueroa , Joanes Lizarraga , Ander Urio , Jon Urrestilla

We develop a new approach to study the nonlinear evolution in the large-scale structure of the Universe both in real space and in redshift space, extending the standard perturbation theory of gravitational instability. Infinite series of…

Astrophysics · Physics 2008-11-26 Takahiko Matsubara

In order to infer the impact of the small-scale physics to the large-scale properties of the universe, we use a series of cosmological $N$-body simulations of self-gravitating matter inhomogeneities to measure, for the first time, the…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-28 Takahiro Nishimichi , Francis Bernardeau , Atsushi Taruya

Using a diagrammatic approach to Eulerian perturbation theory, we analytically calculate the variance and skewness of the density and velocity divergence induced by gravitational evolution from Gaussian initial conditions, including…

Astrophysics · Physics 2011-09-30 Roman Scoccimarro , Joshua Frieman

In this work, we revisit the dynamics of pre-inflationary universe with a family of $\alpha-$attractor potentials, in the framework of loop quantum cosmology, in which the big bang singularity is generically resolved purely with quantum…

General Relativity and Quantum Cosmology · Physics 2020-09-22 M. Shahalam , Mudhahir Al Ajmi , R. Myrzakulov , Anzhong Wang

We examine the importance of second order corrections to linearized cosmological perturbation theory in an inflationary background, taken to be a spatially flat FRW spacetime. The full second order problem is solved in the sense that we…

General Relativity and Quantum Cosmology · Physics 2009-11-11 B. Losic , W. G. Unruh

A generic form of low-energy effective action of superstring theories with one-loop quantum correction is well known. Based on this action we derive the complete perturbation equations and general analytic solutions in the cosmological…

Astrophysics · Physics 2009-10-31 J. Hwang , H. Noh

Linear causal analysis is central to a wide range of important application spanning finance, the physical sciences, and engineering. Much of the existing literature in linear causal analysis operates in the time domain. Unfortunately, the…

Machine Learning · Computer Science 2016-03-11 Francois W. Belletti , Evan R. Sparks , Michael J. Franklin , Alexandre M. Bayen , Joseph E. Gonzalez

This is the second paper in a series of four in which we use space adiabatic methods in order to incorporate backreactions among the homogeneous and between the homogeneous and inhomogeneous degrees of freedom in quantum cosmological…

General Relativity and Quantum Cosmology · Physics 2019-06-20 J. Neuser , S. Schander , T. Thiemann

We continue a previous study about the infrared loop effects in the $D$-dimensional de Sitter space for a real scalar $\phi^4$ theory from the complementary series whose bare mass belongs to the interval $\frac{\sqrt{3}}{4}\,…

High Energy Physics - Theory · Physics 2017-07-12 E. T. Akhmedov , U. Moschella , K. E. Pavlenko , F. K. Popov

In this short note we summarize the arguments against a significant back-reaction of inhomogeneities on the acceleration of the Universe. We also present a quick way to access the importance of back-reaction using the Fourier space…

Cosmology and Nongalactic Astrophysics · Physics 2009-06-25 Houri Ziaeepour
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