Simple Types of Anisotropic Inflation

Abstract

We display some simple cosmological solutions of gravity theories with quadratic Ricci curvature terms added to the Einstein-Hilbert lagrangian which exhibit anisotropic inflation. The Hubble expansion rates are constant and unequal in three orthogonal directions. We describe the evolution of the simplest of these homogeneous and anisotropic cosmological models from its natural initial state and evaluate the deviations they will create from statistical isotropy in the fluctuations produced during a period of anisotropic inflation. The anisotropic inflation is not a late-time attractor in these models but the rate of approach to a final isotropic de Sitter state is slow and is conducive to the creation of observable anisotropic statistical effects in the microwave background. The statistical anisotropy would not be scale invariant and the level of statistical anisotropy will grow with scale.

8pages, 3 figs v2:refs added, typos fixed

References in corpus (20)

• Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Interpretation
• Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Data Processing, Sky Maps, and Basic Results
• Modified f(R) gravity unifying R^m inflation with \LambdaCDM epoch
• Inflationary Universe with Anisotropic Hair
• Hemispherical power asymmetry in the three-year Wilkinson Microwave Anisotropy Probe sky maps
• The Uncorrelated Universe: Statistical Anisotropy and the Vanishing Angular Correlation Function in WMAP Years 1-3
• Estimators for CMB Statistical Anisotropy
• A Hemispherical Power Asymmetry from Inflation
• Cosmic Microwave Background Statistics for a Direction-Dependent Primordial Power Spectrum
• Predictions from an anisotropic inflationary era
• Anisotropic Dark Energy: Dynamics of Background and Perturbations
• Instability of the ACW model, and problems with massive vectors during inflation
• Anisotropic Inflation from Vector Impurity
• On the evolution of universes in quadratic theories of gravity
• The Cosmology of Ricci-Tensor-Squared Gravity in the Palatini Variational Approach
• Non-gaussianity at tree and one-loop levels from vector field perturbations
• Gravity Waves Signatures from Anisotropic pre-Inflation
• Possible extensions of the standard cosmological model: anisotropy, rotation, and magnetic field
• Stable Isotropic Cosmological Singularities in Quadratic Gravity
• The Stability of an Isotropic Cosmological Singularity in Higher-Order Gravity

Cited by in corpus (55)

• Modified Gravity and Cosmology
• Gauge Fields and Inflation
• Scalar-Scalar, Scalar-Tensor, and Tensor-Tensor Correlators from Anisotropic Inflation
• Statistical Anisotropy from Anisotropic Inflation
• Anisotropic Power-law Inflation
• Anisotropic Universe Models in f(T) Gravity
• Revisiting Cosmic No-Hair Theorem for Inflationary Settings
• Anisotropic Inflation from Charged Scalar Fields
• Inflation with stable anisotropic hair: is it cosmologically viable?
• Inflation with Multi-Vector-Hair: The Fate of Anisotropy
• Solving higher curvature gravity theories
• Anisotropic Inflation with Non-Abelian Gauge Kinetic Function
• Probing Dark Energy Anisotropy
• Testing spatial curvature and anisotropic expansion on top of the $\Lambda$CDM model
• Anisotropic cosmological solutions in $R+R^2$ gravity
• Designing Anisotropic Inflation with Form Fields
• Stability of the Kasner Universe in f(T) Gravity
• Curvature Perturbations in Anisotropic Inflation with Symmetry Breaking
• A quantum gravitational inflationary scenario in Bianchi-I spacetime
• Kantowski-Sachs Einstein-æther perfect fluid models
• Issues on Generating Primordial Anisotropies at the End of Inflation
• No-go theorem for inflation in Ricci-inverse gravity
• Generality of Starobinsky and Higgs inflation in the Jordan frame
• Cosmological consequences of a principle of finite amplitudes
• Non-constant volume exponential solutions in higher-dimensional Lovelock cosmologies
• No-go theorem for inflation in an extended Ricci-inverse gravity model
• Attractor behaviour in ELKO cosmology
• Formalizing Anisotropic Inflation in Modified Gravity
• On the initial singularity and extendibility of flat quasi-de Sitter spacetimes
• Accelerating anisotropic cosmologies in Brans-Dicke gravity coupled to a mass-varying vector field
• Self-anisotropizing inflationary universe in Horndeski theory and beyond
• On stability of the Kasner solution in quadratic gravity
• \bf $\delta M$ Formalism: A New Approach to Cosmological Perturbation Theory in Anisotropic Inflation
• Anisotropic constant-roll inflation for the Dirac-Born-Infeld model
• Mathematical General Relativity
• Anisotropic power-law inflation for a conformal-violating Maxwell model
• A new method for testing isotropy with Shannon entropy
• Anisotropic power-law inflation for a model of two scalar and two vector fields
• Anisotropic cosmology and inflation from tilted Bianchi IX model
• Testing isotropy in the Two Micron All-Sky redshift survey with information entropy
• Stable small spatial hairs in a power-law k-inflation model
• CMB imprints of non-canonical anisotropic inflation
• No-hair conjectures, primordial shear and protoinflationary initial conditions
• Open problems in mathematical physics
• The Initial State of a Primordial Anisotropic Stage of Inflation
• Cosmological dynamics in six-order gravity
• Anisotropic hyperbolic inflation for a model of two scalar and two vector fields
• Imprints of a hemispherical power asymmetry in the seven-year WMAP data due to non-commutativity of space-time
• Statistical anisotropy from inflationary magnetogenesis
• Anisotropic power-law inflation for models of non-canonical scalar fields non-minimally coupled to a two-form field
• Imprints of Schwinger Effect on Primordial Spectra
• Viable Anisotropic Inflation and Reheating in the Tachyon Model
• Anisotropic solutions for $R^2$ gravity model with a scalar field
• Stability investigations of de Sitter inflationary solutions in power-law extensions of the Starobinsky model
• Observational Viability of Anisotropic Inflation Revisited