175 citations · 394 across the 5 of their papers we have counts for
5 papers
A Note on the Semi-Classical Approximation in Quantum Gravity
Gilad Lifschytz, Samir D. Mathur, Miguel E. Ortiz
We re-examine the semiclassical approximation to quantum gravity in the canonical formulation, focusing on the definition of a quasiclassical state for the gravitational field. It…
Breakdown of the semiclassical approximation at the black hole horizon
E. Keski-Vakkuri, G. Lifschytz, S. D. Mathur +1
The definition of matter states on spacelike hypersurfaces of a 1+1 dimensional black hole spacetime is considered. The effect of small quantum fluctuations of the mass of the blac…
Relating black holes in two and three dimensions
Ana Achúcarro, Miguel Ortiz
The three dimensional black hole solutions of Bañados, Teitelboim and Zanelli (BTZ) are dimensionally reduced in various different ways. Solutions are obtained to the Jackiw-Teitel…
Sum-over-histories origin of the composition laws of relativistic quantum mechanics and quantum cosmology
Jonathan Halliwell, Miguel Ortiz
The scope of the paper has been broadened to include a more complete discussion of the following topics: The derivation of composition laws in quantum cosmology. The connection bet…
Semilocal strings and monopoles
G. W. Gibbons, M. E. Ortiz, F. Ruiz Ruiz +1
A variation on the abelian Higgs model, with global SU(2) x local U(1) symmetry broken to global U(1) was recently shown by Vachaspati and Achucarro to admit stable, finite energy…