Inflation without Inflaton(s)

Abstract

We propose a model for early universe cosmology without the need for fundamental scalar fields. Cosmic acceleration and phenomenologically viable reheating of the universe results from a series of energy transitions, where during each transition vacuum energy is converted to thermal radiation. We show that this `cascading universe' can lead to successful generation of adiabatic density fluctuations and an observable gravity wave spectrum in some cases, where in the simplest case it reproduces a spectrum similar to slow-roll models of inflation. We also find the model provides a reasonable reheating temperature after inflation ends. This type of model may also be relevant for addressing the smallness of the vacuum energy today.

13 pages, 4 figures, published version

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Cited by in corpus (15)

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• Multi-field Inflation with a Random Potential
• Inflation in the Rényi cosmology
• Does Gravity's Rainbow induce Inflation without an Inflaton?
• Staggered Multi-Field Inflation
• Multi-Field Inflation on the Landscape
• Chain inflation revisited
• Tunneling and propagation of vacuum bubbles on dynamical backgrounds
• Inflation and the cosmological (not-so) constant in unimodular gravity
• Cascades and Collapses, Great Walls and Forbidden Cities: Infinite Towers of Metastable Vacua in Supersymmetric Field Theories
• The Power Spectrum of Density Perturbations in Chain Inflation
• "Old" Locked Inflation
• Exposition to Staggered Multi-Field Inflation
• Radiation Driven Inflation