97 citations · 309 across the 14 of their papers we have counts for
14 papers
The instability of orientifolds and the end of the (string) landscape as we know it
Keith Copsey
Negative mass brane-like objects known as orientifolds are crucial in the construction of all presently understood realistic string compactifications and I review in general the li…
Singularities in Hyperscaling Violating Spacetimes
Keith Copsey, Robert Mann
We examine spacetimes which generalize Lifshitz scaling to allow hyperscaling violation invariance (i.e. a constant conformal transformation) for the types of singularities frequen…
Hidden singularities and closed timelike curves in a proposed dual for Lifshitz-Chern-Simons gauge theories
Keith Copsey, Robert B. Mann
We point out that the metrics recently proposed by K. Balasubramanian and J. McGreevy \cite{BalaMcGreevyLifshitz} as gravitational duals to Lifshitz Chern-Simons gauge theories con…
Coleman-de Luccia reconsidered: a subtlety of gravity and the thin wall approximation
Keith Copsey
I point out that the usual Coleman-de Luccia analysis of tunnelling via instantons between perturbatively stable minima using the thin-wall approximation misses one of the effects…
Gravitation and tunnelling: Subtleties of the thin-wall approximation and rapid decays
Keith Copsey
I provide some simple physical arguments that, once gravitation and some subtleties are taken into account, rather broad classes of potentials result in instantons which tunnel rel…
Pathologies in Asymptotically Lifshitz Spacetimes
Keith Copsey, Robert Mann
There has been significant interest in the last several years in studying possible gravitational duals, known as Lifshitz spacetimes, to anisotropically scaling field theories by a…