76 citations · 201 across the 5 of their papers we have counts for
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astro-ph2003
Conditions for Generating Scale-Invariant Density Perturbations
Steven Gratton, Justin Khoury, Paul J. Steinhardt +1
We analyze the general conditions on the equation of state required for quantum fluctuations of a scalar field to produce a scale-invariant spectrum of density perturbations, i…
gr-qc2003
Inflation without a beginning: a null boundary proposal
Anthony Aguirre, Steven Gratton
We develop our recent suggestion that inflation may be made past eternal, so that there is no initial cosmological singularity or "beginning of time". Inflation with multiple vacua…