295 citations · 3k across the 67 of their papers we have counts for
5 papers · 1 filter
Stochastic Samples versus Vacuum Expectation Values in Cosmology
N. C. Tsamis, Aggelos Tzetzias, R. P. Woodard
Particle theorists typically use expectation values to study the quantum back-reaction on inflation, whereas many cosmologists stress the stochastic nature of the process. While ex…
Primordial Density Perturbations and Reheating from Gravity
N. C. Tsamis, R. P. Woodard
We consider the presence and evolution of primordial density perturbations in a cosmological model based on a simple ansatz which captures -- by providing a set of effective gravit…
Possible Enhancement of High Frequency Gravitational Waves
Maria G. Romania, N. C. Tsamis, R. P. Woodard
We study the tensor perturbations in a class of non-local, purely gravitational models which naturally end inflation in a distinctive phase of oscillations with slight and short vi…
De Sitter Breaking through Infrared Divergences
S. P. Miao, N. C. Tsamis, R. P. Woodard
Just because the propagator of some field obeys a de Sitter invariant equation does not mean it possesses a de Sitter invariant solution. The classic example is the propagator of a…
Post-Inflationary Evolution via Gravitation
N. C. Tsamis, R. P. Woodard
We study a class of non-local, purely gravitational models which have the correct structure to reproduce the leading infrared logarithms of quantum gravitational back-reaction duri…