Alternatives to Cosmological Inflation

Abstract

The inflationary paradigm, although very successful phenomenologically, suffers from several conceptual problems which motivate the search for alternative scenarios of early universe cosmology. Here, two possible alternatives will be reviewed. - "string gas cosmology" and the "matter bounce". Their successes and problems will be pointed out.

14 pages, 5 figures, to be published in the proceedings of CosPA08

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Cited by in corpus (101)

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• The QCD nature of Dark Energy
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• An Extended Matter Bounce Scenario: current status and challenges
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• Trans-Planckian censorship, inflation and excited initial states for perturbations
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• On $R+\alpha R^2$ Loop Quantum Cosmology
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• The trans-Planckian censorship conjecture from the swampland distance conjecture
• Early Structure Formation from Cosmic String Loops in Light of Early JWST Observations
• Indications of de Sitter Spacetime from Classical Sequential Growth Dynamics of Causal Sets
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• Cosmological Perturbations Across an S-brane
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• Eternal Inflation, Entropy Bounds and the Swampland
• Cosmographic analysis of a closed bouncing universe with the varying cosmological constant in $f(R,T)$ gravity
• Emergent Metric Space-Time from Matrix Theory
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• Stability of Hyperbolic and Matter-Dominated Bounce Cosmologies From F(R,G) Modified Gravity at Late Evolution Stages
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• Bouncing cosmologies via modified gravity in the ADM formalism: Application to Loop Quantum Cosmology
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• Cosmological Models Coupled with Dark Matter in a Dissipative Universe
• $f(\mathcal{G},\text{T})$ Gravity Bouncing Universe with Cosmological Parameters
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• On the TransPlanckian Censorship Conjecture in Holographic Cosmology
• Measuring the Energy Scale of Inflation with Large Scale Structures
• The matter-ekpyrotic bounce scenario in Loop Quantum Cosmology
• Investigating the physical and geometrical parameters of the cosmological models with anisotropic background
• Gravitational Particle Production in Loop Quantum Cosmology
• A pure general relativistic non-singular bouncing origin for the Universe
• Cosmic Strings and the Origin of Globular Clusters
• Quasi-matter bounce and inflation in the light of the CSL model
• Non-Gaussian signatures of general inflationary trajectories
• Viscous Accelerating Universe with Non-linear and Logarithmic Equation of State Fluid
• Thermal and quantum induced early superstring cosmology
• Unitarity Problems for an Effective Field Theory Description of Early Universe Cosmology
• Parity violation in primordial tensor non-Gaussianities from matter bounce cosmology
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• Interpreting Pulsar Timing Array data of Gravitational Waves with Ekpyrosis-Bouncing Cosmology
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• Imprints of Anisotropy on the Power Spectrum in Matter Dominated Bouncing Universe as Background
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