Inflating an Inhomogeneous Universe

Abstract

While cosmological inflation can erase primordial inhomogeneities, it is possible that inflation may not begin in a significantly inhomogeneous universe. This issue is particularly pressing in multifield scenarios, where even the homogeneous dynamics may depend sensitively on the initial configuration. This paper presents an initial survey of the onset of inflation in multifield models, via qualitative lattice-based simulations that do not include local gravitational backreaction. Using hybrid inflation as a test model, our results suggest that small subhorizon inhomogeneities do play a key role in determining whether inflation begins in multifield scenarios. Interestingly, some configurations which do not inflate in the homogeneous limit "succeed" after inhomogeneity is included, while other initial configurations which inflate in the homogeneous limit "fail" when inhomogeneity is added.

arXiv comment15 pages, 8 figures, 1 table; v2: references added; v3: matches published version

References in corpus (41)

• Nine-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Parameter Results
• Nine-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Final Maps and Results
• SDSS-III: Massive Spectroscopic Surveys of the Distant Universe, the Milky Way Galaxy, and Extra-Solar Planetary Systems
• The 2dF Galaxy Redshift Survey: Power-spectrum analysis of the final dataset and cosmological implications
• Hybrid Inflation
• False Vacuum Inflation with Einstein Gravity
• Flux Compactification
• Flux compactifications in string theory: a comprehensive review
• Large Scale Structure and Supersymmetric Inflation without Fine Tuning
• A Measurement of the Cosmic Microwave Background Damping Tail from the 2500-square-degree SPT-SZ survey
• Inflationary paradigm in trouble after Planck2013
• Constraints on Cosmology from the Cosmic Microwave Background Power Spectrum of the 2500 ${\mathrm{deg}}^2$ SPT-SZ Survey
• LATTICEEASY: A Program for Lattice Simulations of Scalar Fields in an Expanding Universe
• Inflationary paradigm after Planck 2013
• A new framework for analyzing the effects of small scale inhomogeneities in cosmology
• Physics of String Flux Compactifications
• Causality and Cosmic Inflation
• Improved Primordial Non-Gaussianity Constraints from Measurements of Galaxy Clustering and the Integrated Sachs-Wolfe Effect
• Creation of a Compact Topologically Nontrivial Inflationary Universe
• DEFROST: A New Code for Simulating Preheating after Inflation
• Hybrid inflation along waterfall trajectories
• On the measure problem in slow roll inflation and loop quantum cosmology
• Inhomogeneous Inflation: Numerical Evolution
• PSpectRe: A Pseudo-Spectral Code for (P)reheating
• Simple predictions from multifield inflationary models
• Initial Conditions for Smooth Hybrid Inflation
• Hybrid Inflation in the Complex Plane
• On the waterfall behavior in hybrid inflation
• Fine tuning of the initial conditions for hybrid inflation
• Initial conditions for hybrid inflation
• Inflationary Attractors and their Measures
• Fractal initial conditions and natural parameter values in hybrid inflation
• Avoiding the blue spectrum and the fine-tuning of initial conditions in hybrid inflation
• Inflationary Initial Conditions Consistent with Causality
• Simulating the universe(s): from cosmic bubble collisions to cosmological observables with numerical relativity
• Initial Conditions for Supersymmetric Inflation
• Non-Gaussianities and Curvature Perturbations from Hybrid Inflation
• Chaotic Dynamics and Two-Field Inflation
• Fine-Tuning Solution for Hybrid Inflation in Dissipative Chaotic Dynamics
• Initial conditions and sampling for multifield inflation
• What is the Homogeneity of our Universe Telling Us?

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• Cosmological Attractors and Initial Conditions for Inflation
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• Robustness of Inflation to Inhomogeneous Initial Conditions
• Initial Conditions for Inflation - A Short Review
• Inflation after Planck: Judgment Day
• Robustness of Inflation to Large Tensor Perturbations
• The Effects of Potential Shape on Inhomogeneous Inflation
• MultiModeCode: An efficient numerical solver for multifield inflation
• Inhomogeneous initial conditions for inflation: A wibbly-wobbly timey-wimey path to salvation
• Geodesic completeness and homogeneity condition for cosmic inflation
• On the initial conditions for inflation with plateau potentials: the $R+R^2$ (super)gravity case
• A Bumpy Start to a Smooth Ride: Onset of Inflation amid Backreaction from Inhomogeneities
• On the initial singularity and extendibility of flat quasi-de Sitter spacetimes
• Starting inflation from inhomogeneous initial conditions with momentum
• Gravitational dynamics in Higgs inflation: Preinflation and preheating with an auxiliary field
• Dynamics of inflation with mutually orthogonal vector fields in a closed universe
• Inhomogeneous Initial Data and Small-Field Inflation
• Robustness of inflation to kinetic inhomogeneities
• Introduction to the number of $e$-folds in slow-roll inflation
• Quantum potentiality in Inhomogeneous Cosmology
• Updated Constraints on Large Field Hybrid Inflation
• A solution to the initial condition problems of inflation : NATON
• TwInflation
• The Dynamics of Inhomogeneous Dark Energy
• Primordial gravitational waves and perturbations during an inhomogeneous inflation