Detection Limits for Super-Hubble Suppression of Causal Fluctuations

Abstract

We investigate to what extent future microwave background experiments might be able to detect a suppression of fluctuation power on large scales in flat and open universe models. Such suppression would arise if fluctuations are generated by causal processes, and a measurement of a small suppression scale would be problematic for inflation models, but consistent with many defect models. More speculatively, a measurement of a suppression scale of the order of the present Hubble radius could provide independent evidence for a fine-tuned inflation model leading to a low-density universe. We find that, depending on the primordial power spectrum, a suppression scale modestly larger than the visible Horizon can be detected, but that the detectability drops very rapidly with increasing scale. For models with two periods of inflation, there is essentially no possibility of detecting a causal suppression scale.

8 pages, 4 figures, revtex, In Press Physical Review D 2000

References in corpus (8)

• Warm Inflation in the Adiabatic Regime- a Model, an Existence Proof for Inflationary Dynamics in Quantum Field Theory
• Perturbation Spectra in the Warm Inflationary Scenario
• A First Principles Warm Inflation Model that Solves the Cosmological Horizon/Flatness Problems
• The correlation of peaks in the microwave background
• An Attempt to Determine the Largest Scale of Primordial Density Perturbations in the Universe
• Dynamical Supersymmetric Inflation
• Density Perturbations of Thermal Origin During Inflation
• Inverting the Sachs-Wolfe Formula: an Inverse Problem Arising in Early-Universe Cosmology

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• Asymmetric inflation: exact solutions
• Non-Gaussianity in the WMAP data using the peak-peak correlation function
• Pre-slow roll initial conditions: large scale power suppression and infrared aspects during inflation
• Role of trans-Planckian modes in cosmology
• Radiative Corrections to the Inflaton Potential as an Explanation of Suppressed Large Scale Power in Density Perturbations and the Cosmic Microwave Background