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Equilateral Non-Gaussianity and New Physics on the Horizon
We examine the effective theory of single-field inflation in the limit where the scalar perturbations propagate with a small speed of sound. In this case the non-linearly realized time-translation
Cosmological non-linearities as an effective fluid
The universe is smooth on large scales but very inhomogeneous on small scales. Why is the spacetime on large scales modeled to a good approximation by the Friedmann equations? Are we sure that
Inflation and String Theory
We review cosmological inflation and its realization in quantum field theory and in string theory. This material is a portion of a book, also entitled "Inflation and String Theory", to be published
TASI Lectures on Inflation
In a series of five lectures I review inflationary cosmology. I begin with a description of the initial conditions problems of the Friedmann-Robertson-Walker (FRW) cosmology and then explain how
Towards an Explicit Model of D-brane Inflation
We present a detailed analysis of an explicit model of warped D-brane inflation, incorporating the effects of moduli stabilization. We consider the potential for D3-brane motion in a warped conifold
CMBPol Mission Concept Study Probing Ination with CMB Polarization
We summarize the utility of precise cosmic microwave background (CMB) polarization measurements as probes of the physics of ination. We focus on the prospects for using CMB measurements
On D3-brane Potentials in Compactifications with Fluxes and Wrapped D-branes
We study the potential governing D3-brane motion in a warped throat region of a string compactification with internal fluxes and wrapped D-branes. If the Kahler moduli of the compact space are
Non-Gaussianity as a particle detector
A bstractWe study the imprints of massive particles with spin on cosmological correlators. Using the framework of the effective field theory of inflation, we classify the couplings of these particles
D3-brane potentials from fluxes in AdS/CFT
We give a comprehensive treatment of the scalar potential for a D3-brane in a warped conifold region of a compactification with stabilized moduli. By studying general ultraviolet perturbations in
The cosmological bootstrap: inflationary correlators from symmetries and singularities
Scattering amplitudes at weak coupling are highly constrained by Lorentz invariance, locality and unitarity, and depend on model details only through coupling constants and the particle content of