105 citations · 274 across the 8 of their papers we have counts for
5 papers · 1 filter
Classical and quantum radiation reaction in conformally flat spacetime
A. Higuchi, P. J. Walker
We investigate the physics of a charged scalar particle moving in conformally flat spacetime with the conformal factor depending only on time in the framework of quantum electrodyn…
Topological censorship and chronology protection
John L. Friedman, Atsushi Higuchi
Over the past two decades, substantial efforts have been made to understand the way in which physics enforces the ordinary topology and causal structure that we observe, from subnu…
The covariant graviton propagator in de Sitter spacetime
Atsushi Higuchi, Spyros S. Kouris
We consider the covariant graviton propagator in de Sitter spacetime in a gauge with two parameters, alpha and beta, in the Euclidean approach. We give an explicit form of the prop…
Large-distance behaviour of the graviton two-point function in de Sitter spacetime
A. Higuchi, S. S. Kouris
It is known that the graviton two-point function for the de Sitter invariant "Euclidean" vacuum in a physical gauge grows logarithmically with distance in spatially-flat de Sitter…
Quantum field theory in Lorentzian universes-from-nothing
John L. Friedman, Atsushi Higuchi
We examine quantum field theory in spacetimes that are time nonorientable but have no other causal pathology. These are Lorentzian universes-from-nothing, spacetimes with a single…