Inflationary buildup of a vector field condensate and its cosmological consequences

Abstract

Light vector fields during inflation obtain a superhorizon perturbation spectrum when their conformal invariance is appropriately broken. Such perturbations, by means of some suitable mechanism (e.g. the vector curvaton mechanism), can contribute to the curvature perturbation in the Universe and produce characteristic signals, such as statistical anisotropy, on the microwave sky, most recently surveyed by the Planck satellite mission. The magnitude of such characteristic features crucially depends on the magnitude of the vector condensate generated during inflation. However, the expectation value of this condensate has so-far been taken as a free parameter, lacking a definite prediction or a physically motivated estimate. In this paper, we study the stochastic evolution of the vector condensate and obtain an estimate for its magnitude. Our study is mainly focused in the supergravity inspired case when the kinetic function and mass of the vector boson is time-varying during inflation, but other cases are also explored such as a parity violating axial theory or a non-minimal coupling between the vector field and gravity. As an example, we apply our findings in the context of the vector curvaton mechanism and contrast our results with current observations.

31 pages, no figures

References in corpus (36)

• Planck 2013 results. XVI. Cosmological parameters
• Inflationary Universe with Anisotropic Hair
• Gauge Fields and Inflation
• Vector Inflation
• Generation of Large-Scale Magnetic Fields in Single-Field Inflation
• Chromo-Natural Inflation: Natural inflation on a steep potential with classical non-Abelian gauge fields
• Instability of anisotropic cosmological solutions supported by vector fields
• The anisotropic power spectrum and bispectrum in the f(phi) F^2 mechanism
• The Nature of Primordial Fluctuations from Anisotropic Inflation
• Scalar-Scalar, Scalar-Tensor, and Tensor-Tensor Correlators from Anisotropic Inflation
• Statistical Anisotropy from Anisotropic Inflation
• Anisotropic Power-law Inflation
• Can a vector field be responsible for the curvature perturbation in the Universe?
• Instability of the ACW model, and problems with massive vectors during inflation
• Anisotropic Inflation from Vector Impurity
• Limits on anisotropic inflation from the Planck data
• Anisotropy in solid inflation
• Anisotropic non-Gaussianity from vector field perturbations
• Gauge-flation trajectories in Chromo-Natural Inflation
• Particle Production of Vector Fields: Scale Invariance is Attractive
• Low-Energy Effective Field Theory for Chromo-Natural Inflation
• Non-minimally coupled vector curvaton
• Gauge-flation and Cosmic No-Hair Conjecture
• Curvature Perturbations in Anisotropic Inflation with Symmetry Breaking
• Parity Violating Statistical Anisotropy
• Gravitational waves in vector inflation
• Supergravity inspired Vector Curvaton
• The statistically anisotropic curvature perturbation generated by f(ϕ)^2 F^2
• On the health of a vector field with (R A^2)/6 coupling to gravity
• Modulated curvaton decay
• Statistical Anisotropy from Vector Curvaton in D-brane Inflation
• Curvature Perturbations from a Massive Vector Curvaton
• On the fate of coupled flat directions during inflation
• Modulation of the waterfall by a gauge field
• D-branes and cosmic structure
• The Vector Curvaton

Cited by in corpus (5)

• Vector Coherent Oscillation Dark Matter
• Non-perturbative approach for curvature perturbations in stochastic-$\delta N$ formalism
• Constraint on Vector Coherent Oscillation Dark Matter with Kinetic Function
• Statistics of Anisotropies in Inflation with Spectator Vector Fields
• The inflationary origin of the Cold Spot anomaly