Gravitational Thermodynamics of Space-time Foam in One-loop Approximation

We show from one-loop quantum gravity and statistical thermodynamics that the thermodynamics of quantum foam in flat space-time and Schwarzschild space-time is exactly the same as that of Hawking-Unruh radiation in thermal equilibrium. This means we show unambiguously that Hawking-Unruh thermal radiation should contain thermal gravitons or the contribution of quantum space-time foam. As a by-product, we give also the quantum gravity correction in one-loop approximation to the classical black hole thermodynamics.Comment: 7 pages, revte

Precise Formulation of Neutrino Oscillation in the Earth

We give a perturbation theory of neutrino oscillation in the Earth. The perturbation theory is valid for neutrinos with energy E \gsim 0.5 GeV. It is formulated using trajectory dependent average potential. Non-adiabatic contributions are included as the first order effects in the perturbation theory. We analyze neutrino oscillation with standard matter effect and with non-standard matter effect. In a three flavor analysis we show that the perturbation theory gives a precise description of neutrino conversion in the Earth. Effect of the Earth matter is substantially simplified in this formulation.Comment: References added, 21 pages, 10 figures, version to appear in PR

Combined transbrachial and transfemoral strategy to deploy an iliac branch endoprosthesis in the setting of a pre-existing endovascular aortic aneurysm repair

This article describes brachial access to position a long sheath in the abdominal aorta in conjunction with a large caliber sheath via the femoral artery ipsilateral to the target site to deliver a 0.018 bodyfloss wire. This bodyfloss wire is inserted into the precannulation port of the iliac branch endoprosthesis (W. L. Gore and Associates, Flagstaff, Ariz), which is then advanced from the groin. Once the bifurcated device is deployed, hypogastric access and stenting is achieved from the upper extremity. This technique is an alternative to safely extend the distal seal while preserving the hypogastric artery and has the advantage of limited iliac bifurcation manipulation

Growth and characteristics of type-II InAs/GaSb superlattice-based detectors

We report on growth and device performance of infrared photodetectors based on type II InAs/Ga(In)Sb strain layer superlattices (SLs) using the complementary barrier infrared detector (CBIRD) design. The unipolar barriers on either side of the absorber in the CBIRD design in combination with the type-II InAs/GaSb superlattice material system are expected to outperform traditional III-V LWIR imaging technologies and offer significant advantages over the conventional II-VI material based FPAs. The innovative design of CBIRDS, low defect density material growth, and robust fabrication processes have resulted in the development of high performance long wave infrared (LWIR) focal plane arrays at JPL

Coarse-Graining and Renormalization Group in the Einstein Universe

The Kadanoff-Wilson renormalization group approach for a scalar self-interacting field theor generally coupled with gravity is presented. An average potential that monitors the fluctuations of the blocked field in different scaling regimes is constructed in a nonflat background and explicitly computed within the loop-expansion approximation for an Einstein universe. The curvature turns out to be dominant in setting the crossover scale from a double-peak and a symmetric distribution of the block variables. The evolution of all the coupling constants generated by the blocking procedure is examined: the renormalized trajectories agree with the standard perturbative results for the relevant vertices near the ultraviolet fixed point, but new effective interactions between gravity and matter are present. The flow of the conformal coupling constant is therefore analyzed in the improved scheme and the infrared fixed point is reached for arbitrary values of the renormalized parameters.Comment: 18 pages, REVTex, two uuencoded figures. (to appear in Phys. Rev. D15, July) Transmission errors have been correcte

The decay and collisions of dark solitons in superfluid Fermi gases

We study soliton collisions and the decay of solitons into sound in superfluid Fermi gases across the Bose-Einstein condensate to Bardeen-Cooper-Schrieffer (BEC-BCS) crossover by performing numerical simulations of the time-dependent Bogoliubov-de Gennes equations. This decay process occurs when the solitons are accelerated to the bulk pair-breaking speed by an external potential. A similar decay process may occur when solitons are accelerated by an inelastic collision with another soliton. We find that soliton collisions become increasingly inelastic as we move from the BEC to BCS regimes, and the excess energy is converted into sound. We interpret this effect as being due to evolution of Andreev bound states localized within the soliton.Comment: 9 pages, 5 figure

On the Connection Between Momentum Cutoff and Operator Cutoff Regularizations

Operator cutoff regularization based on the original Schwinger's proper-time formalism is examined. By constructing a regulating smearing function for the proper-time integration, we show how this regularization scheme simulates the usual momentum cutoff prescription yet preserves gauge symmetry even in the presence of the cutoff scales. Similarity between the operator cutoff regularization and the method of higher (covariant) derivatives is also observed. The invariant nature of the operator cutoff regularization makes it a promising tool for exploring the renormalization group flow of gauge theories in the spirit of Wilson-Kadanoff blocking transformation.Comment: 28 pages in plain TeX, no figures. revised and expande

Sub and Super-Luminal Propagation of Intense Pulses in Media with Saturated and Reverse Absorption

We develop models for the propagation of intense pulses in solid state media which can have either saturated absorption or exhibit reverse absorption . We show that the experiments of Bigelow {\it et al.}[Phys. Rev. Lett. {\bf 90}, 113903 (2003); Science {\bf 301}, 200 (2003).] on subluminal propagation in Ruby and superluminal propagation in Alexandrite are well explained by modelling them as three level and four level systems coupled to Maxwell equations. We present results well beyond the traditional pump-probe approach.Comment: 4 pages, 6 figure

Generalization of Friedberg-Lee Symmetry

We study the possible origin of Friedberg-Lee symmetry. First, we propose the generalized Friedberg-Lee symmetry in the potential by including the scalar fields in the field transformations, which can be broken down to the FL symmetry spontaneously. We show that the generalized Friedberg-Lee symmetry allows a typical form of Yukawa couplings, and the realistic neutrino masses and mixings can be generated via see-saw mechanism. If the right-handed neutrinos transform non-trivially under the generalized Friedberg-Lee symmetry, we can have the testable TeV scale see-saw mechanism. Second, we present two models with the $SO(3)\times U(1)$ global flavour symmetry in the lepton sector. After the flavour symmetry breaking, we can obtain the charged lepton masses, and explain the neutrino masses and mixings via see-saw mechanism. Interestingly, the complete neutrino mass matrices are similar to those of the above models with generalized Friedberg-Lee symmetry. So the Friedberg-Lee symmetry is the residual symmetry in the neutrino mass matrix after the $SO(3)\times U(1)$ flavour symmetry breaking.Comment: 16 pages, no figure, version published in PR