Scalar tilt from broken conformal invariance

Abstract

Within recently proposed scenario which explains flatness of the spectrum of scalar cosmological perturbations by a combination of conformal and global symmetries, we discuss the effect of weak breaking of conformal invariance. We find that the scalar power spectrum obtains a small tilt which depends on both the strength of conformal symmetry breaking and the law of evolution of the scale factor.

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Cited by in corpus (21)

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• Non-linear Realizations of Conformal Symmetry and Effective Field Theory for the Pseudo-Conformal Universe
• Emergent Universe Scenario via Quintom Matter
• From Satisfying to Violating the Null Energy Condition
• Inflation from Minkowski Space
• Constraining anisotropic models of the early Universe with WMAP9 data
• Non-Gaussianity of scalar perturbations generated by conformal mechanisms
• Cosmology of the Spinor Emergent Universe and Scale-invariant Perturbations
• Properties of scalar perturbations generated by conformal scalar field
• Scale-Invariant Fluctuations from Galilean Genesis
• Cosmological spectrum of two-point correlation function from vacuum fluctuation of Stringy Axion field in De Sitter space: A study of the role of Quantum Entanglement
• Scalar perturbations in conformal rolling scenario with intermediate stage
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• Revisiting constraints on (pseudo)conformal Universe with Planck data
• On holography for (pseudo-)conformal cosmology
• Towards conformal cosmology
• Conformal Universe as false vacuum decay
• Perturbations on and off de Sitter brane in anti-de Sitter bulk
• Weakly Broken Galileon Symmetry in Cosmology