Challenges for String Cosmology

Abstract

We critically assess the twin prospects of describing the observed universe in string theory, and using cosmological experiments to probe string theory. For the purposes of this short review, we focus on the limitations imposed by our incomplete understanding of string theory. After presenting an array of significant obstacles, we indicate a few areas that may admit theoretical progress in the near future.

18 pages; contribution to a focus issue on string cosmology for Classical and Quantum Gravity

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Cited by in corpus (48)

• A Critical Review of Classical Bouncing Cosmologies
• Features and New Physical Scales in Primordial Observables: Theory and Observation
• Effective theories of single field inflation when heavy fields matter
• D-Branes at del Pezzo Singularities: Global Embedding and Moduli Stabilisation
• String Inflation After Planck 2013
• Life at the Interface of Particle Physics and String Theory
• Observable gravitational waves from inflation with small field excursions
• Inflating in a Trough: Single-Field Effective Theory from Multiple-Field Curved Valleys
• Higgs-otic Inflation and String Theory
• Closed String Thermodynamics and a Blue Tensor Spectrum
• Dark D-brane Cosmology
• Modulated Reheating and Large Non-Gaussianity in String Cosmology
• Quantum Gravity Constraints on Inflation
• Large Field Inflation from Axion Mixing
• Multi-field inflation with random potentials: field dimension, feature scale and non-Gaussianity
• Inflating with Large Effective Fields
• Observational effects from quantum cosmology
• Brane-Antibrane Backreaction in Axion Monodromy Inflation
• Cosmological perturbations in non-local higher-derivative gravity
• Cosmological singularities, entanglement and quantum extremal surfaces
• Statistical Anisotropy from Vector Curvaton in D-brane Inflation
• Accidental Inflation in the Landscape
• Entanglement Entropy Near Cosmological Singularities
• de Sitter Swampland Conjecture in String Field Inflation
• Unconventional Cosmology
• The Web of D-branes at Singularities in Compact Calabi-Yau Manifolds
• Cosmology of Axions and Moduli: A Dynamical Systems Approach
• Inflation by Alignment
• Cosmologies, singularities and quantum extremal surfaces
• On the Trispectrum of Galileon Inflation
• The Overshoot Problem in Inflation after Tunneling
• Multi-Stream Inflation in a Landscape
• Magnon Inflation: Slow Roll with Steep Potentials
• Clearing the Brush: The Last Stand of Solo Small Field Inflation
• Goldilocks Models of Higher-Dimensional Inflation (including modulus stabilization)
• Adiabatic and isocurvature perturbations in extended theories with kinetic couplings
• Constraining dark energy
• The Trispectrum in the Effective Theory of Inflation with Galilean symmetry
• Orbifold Line Topology and the Cosmic Microwave Background
• Wavefunction for the Universe Circa the Beginning with Dynamically Determined Unique Initial Conditions
• Stringy Corrections to the Classical Tests of General Relativity
• Early Universe Cosmology, Effective Supergravity, and Invariants of Algebraic Forms
• Towards brane-antibrane inflation in type $I{I}_A$: The holographic MQCD model
• Cosmological singularities, AdS/CFT and de Sitter deformations
• Non-perpetual Eternal Inflation and the Emergent de Sitter Swampland Conjecture
• Supersymmetric Horizons at the Edge of Effective Field Theory
• The dangerous irrelevance of string theory
• Warped spherical compactifications in the gravity theory