35 research outputs found
Superconducting circuit boundary conditions beyond the Dynamical Casimir Effect
We study analytically the time-dependent boundary conditions of
superconducting microwave circuit experiments in the high plasma frequency
limit, in which the conditions are Robin-type and relate the value of the field
to the spatial derivative of the field. We give an explicit solution to the
field evolution for boundary condition modulations that are small in magnitude
but may have arbitrary time dependence, in a formalism that applies both to a
semiopen waveguide and to a closed waveguide with two independently adjustable
boundaries. The correspondence between the microwave Robin boundary conditions
and the mechanically-moving Dirichlet boundary conditions of the Dynamical
Casimir Effect is shown to break down at high field frequencies, approximately
one order of magnitude above the frequencies probed in the 2011 experiment of
Wilson et al. Our results bound the parameter regime in which a microwave
circuit can be used to model relativistic effects in a mechanically-moving
cavity, and they show that beyond this parameter regime moving mirrors produce
more particles and generate more entanglement than their non-moving microwave
waveguide simulations.Comment: 29 pages, 2 figures. v3: minor updates, including a change in the
title. Published versio
Exact constraints on D Myers Perry black holes and the Wald Problem
Exact relations on the existence of event horizons of Myers Perry black holes
are obtained in dimensions. It is further shown that naked
singularities can not be produced by "spinning-up" these black holes by
shooting particles into their equatorial planes.Comment: 7 pages, 11 figures, version two corrects an earlier error in
equation (35) and adds some plots for cohomogeneity-2 and 3 black hole
Ruling out stray thermal radiation in analogue black holes
Experimental searches for the thermal radiation from analogue black holes
require the measurement of very low temperatures in regimes where other thermal
noises may interfere or even mimic the sought-after effect. In this letter, we
parameterize the family of bosonic thermal channels which give rise to such
thermal effects and show that by use of coherent states and homodyne detection
one can rule out the non-Hawking contributions and identify those candidate
sources which arise from Hawking-like processes.Comment: 5 pages, 2 figure
Lepton number violation via intermediate black hole processes
Black holes at the TeV scale are investigated in the extra large dimension
scenario. We interpret the lightest black hole excitation as a singlet scalar
field, and show how interaction terms can be appended to the standard model at
the dimension five non-renormalizable level. Lepton family number violation is
natural in this model. Muon magnetic moment, and neutrino masses are
investigated. We also present a quantization scheme in n dimensions.Comment: 5 pages, 4 figure
Entanglement of two qubits in a relativistic orbit
The creation and destruction of entanglement between a pair of interacting
two-level detectors accelerating about diametrically opposite points of a
circular path is investigated. It is found that any non-zero acceleration has
the effect of suppressing the vacuum entanglement and enhancing the
acceleration radiation thereby reducing the entangling capacity of the
detectors. Given that for large accelerations the acceleration radiation is the
dominant effect, we investigate the evolution of a two detector system
initially prepared in a Bell state using a perturbative mater equation and
treating the vacuum fluctuations as an unobserved environment. A general
function for the concurrence is obtained for stationary and symmetric
worldlines in flatspace. The entanglement sudden death time is computed.Comment: v2: Some typo's fixed, figures compressed to smaller filesize and
added some references
Graviton emission from simply rotating Kerr-de Sitter black holes: Transverse traceless tensor graviton modes
In this article we present results for tensor graviton modes (in seven
dimensions and greater, ) for greybody factors of Kerr-dS black holes
and for Hawking radiation from simply rotating (n+4)-dimensional Kerr black
holes. Although there is some subtlety with defining the Hawking temperature of
a Kerr-dS black hole, we present some preliminary results for emissions
assuming the standard Hawking normalization and a Bousso-Hawking-like
normalization.Comment: 12 pages, 18 figure
Black hole quasinormal modes using the asymptotic iteration method
In this article we show that the asymptotic iteration method (AIM) allows one
to numerically find the quasinormal modes of Schwarzschild and Schwarzschild de
Sitter (SdS) black holes. An added benefit of the method is that it can also be
used to calculate the Schwarzschild anti-de Sitter (SAdS) quasinormal modes for
the case of spin zero perturbations. We also discuss an improved version of the
AIM, more suitable for numerical implementation.Comment: 10 pages, LaTeX; references added; substantially expanded versio