201 citations · 1.8k across the 54 of their papers we have counts for
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A gradient expansion for cosmological backreaction
Kari Enqvist, Shaun Hotchkiss, Gerasimos Rigopoulos
We address the issue of cosmological backreaction from non-linear structure formation by constructing an approximation for the time evolved metric of a dust dominated universe base…
Fluctuations along supersymmetric flat directions during Inflation
Kari Enqvist, Daniel G. Figueroa, Gerasimos Rigopoulos
We consider a set of scalar fields, consisting of a single flat direction and one or several non-flat directions. We take our cue from the MSSM, considering separately D-flat and F…
Non-metric chaotic inflation
Kari Enqvist, Tomi Koivisto, Gerasimos Rigopoulos
We consider inflation within the context of what is arguably the simplest non-metric extension of Einstein gravity. There non-metricity is described by a single graviscalar field w…
Self Regulation of Infrared Correlations for Massless Scalar Fields during Inflation
Bjorn Garbrecht, Gerasimos Rigopoulos
Self-energies of a minimally coupled scalar field with quartic and trilinear interactions are calculated in a de Sitter background, using a position space propagator. For quartic i…
Gauge invariance and non-Gaussianity in Inflation
Gerasimos Rigopoulos
We clarify the role of gauge invariance for the computation of quantum non-Gaussian correlators in inflation. A gauge invariant generating functional for n-point functions is given…