Cosmology from an AdS Schwarzschild black hole via holography

We derive the equations of cosmological evolution from an AdS Schwarzschild black hole via holographic renormalization with appropriate boundary conditions.Comment: 6 page

Scottish show

Jurried exhibtion of five selected artists. Healey was one of five invited artists. Artworks selected by Gallery panel. Printed catalogue of artworks

Rindler and Minkowski particles relationship revisited

We show that the emission of a Minkowski particle by a general class of scalar sources as described by inertial observers corresponds to either the emission or the absorption of a Rindler particle as described by uniformly accelerated observers. Our results are discussed in connection with the current controversy whether uniformly accelerated detectors radiate.Comment: To appear in Physics Letters B, 9 pages, LATEX, no-figure

Is the equivalence for the response of static scalar sources in the Schwarzschild and Rindler spacetimes valid only in four dimensions?

It was shown recently that in four dimensions scalar sources with fixed proper acceleration minimally coupled to a massless Klein-Gordon field lead to the same responses when they are (i) uniformly accelerated in Minkowski spacetime (in the inertial vacuum) and (ii) static in the Schwarzschild spacetime (in the Unruh vacuum). Here we show that this equivalence is broken if the spacetime dimension is more than four.Comment: 4 pages, 1 figur

Coordinate representation of particle dynamics in AdS and in generic static spacetimes

We discuss the quantum dynamics of a particle in static curved spacetimes in a coordinate representation. The scheme is based on the analysis of the squared energy operator E^2, which is quadratic in momenta and contains a scalar curvature term. Our main emphasis is on AdS spaces, where this term is fixed by the isometry group. As a byproduct the isometry generators are constructed and the energy spectrum is reproduced. In the massless case the conformal symmetry is realized as well. We show the equivalence between this quantization and the covariant quantization, based on the Klein-Gordon type equation in AdS. We further demonstrate that the two quantization methods in an arbitrary (N+1)-dimensional static spacetime are equivalent to each other if the scalar curvature terms both in the operator E^2 and in the Klein-Gordon type equation have the same coefficient equal to (N-1)/(4N).Comment: 14 pages, no figures, typos correcte

Awaking the vacuum in relativistic stars

Void of any inherent structure in classical physics, the vacuum has revealed to be incredibly crowded with all sorts of processes in relativistic quantum physics. Yet, its direct effects are usually so subtle that its structure remains almost as evasive as in classical physics. Here, in contrast, we report on the discovery of a novel effect according to which the vacuum is compelled to play an unexpected central role in an astrophysical context. We show that the formation of relativistic stars may lead the vacuum energy density of a quantum field to an exponential growth. The vacuum-driven evolution which would then follow may lead to unexpected implications for astrophysics, while the observation of stable neutron-star configurations may teach us much on the field content of our Universe.Comment: To appear in Phys. Rev. Let

TEMPERATURE AND RELATIVITY

We investigate whether inertial thermometers moving in a thermal bath behave as being hotter or colder. This question is directly related to the classical controversy concerning how temperature transforms under Lorentz transformations. Rather than basing our arguments on thermodynamical hypotheses, we perform straightforward calculations in the context of relativistic quantum field theory. For this purpose we use Unruh-DeWitt detectors, since they have been shown to be reliable thermometers in semi-classical gravity. We believe that our discussion helps in definitely clarifying this issue.Comment: 9 pages, 1 figure available upon reques