43 citations · 71 across the 8 of their papers we have counts for
8 papers
Ambiguities in second-order cosmological perturbations for non-canonical scalar fields
Corrado Appignani, Roberto Casadio, S. Shankaranarayanan
Over the last few years, it was realised that non-canonical scalar fields can lead to the accelerated expansion in the early universe. The primordial spectrum in these scenarios no…
The Cosmological Constant and Horava-Lifshitz Gravity
Corrado Appignani, Roberto Casadio, S. Shankaranarayanan
Horava-Lifshitz theory of gravity with detailed balance is plagued by the presence of a negative bare (or geometrical) cosmological constant which makes its cosmology clash with ob…
A note on second-order perturbations of non-canonical scalar fields
Corrado Appignani, Roberto Casadio, S. Shankaranarayanan
We study second-order perturbations for a general non-canonical scalar field, minimally coupled to gravity, on the unperturbed FRW background, where metric fluctuations are neglect…
A radiation-like era before inflation
Corrado Appignani, Roberto Casadio
We show that the semiclassical approximation to the Wheeler-DeWitt equation for the minisuperspace of a minimally coupled scalar field in the spatially flat de Sitter Universe prom…
Hints of (trans-Planckian) asymptotic freedom in semiclassical cosmology
Corrado Appignani, Roberto Casadio
We employ the semiclassical approximation to the Wheeler-DeWitt equation in the spatially flat de Sitter Universe to investigate the dynamics of a minimally coupled scalar field ne…
Inflation and the semiclassical dynamics of a conformal scalar field
G. L. Alberghi, C. Appignani, R. Casadio +2
We derive the semiclassical evolution of massless conformally coupled scalar matter in the de Sitter space-time from the Born-Oppenheimer reduction of the Wheeler-DeWitt equation.…