A New Perspective on Path Integral Quantum Mechanics in Curved Space-Time

A fundamentally different approach to path integral quantum mechanics in curved space-time is presented, as compared to the standard approaches currently available in the literature. Within the context of scalar particle propagation in a locally curved background, such as described by Fermi or Riemann normal co-ordinates, this approach requires use of a constructed operator to rotate the initial, intermediate, and final position ket vectors onto their respective local tangent spaces, defined at each local time step along some arbitrary classical reference worldline. Local time translation is described using a quantum mechanical representation of Lie transport, that while strictly non-unitary in operator form, nevertheless correctly recovers the free-particle Lagrangian in curved space-time, along with new contributions. This propagator yields the prediction that all probability violating terms due to curvature contribute to a quantum violation of the weak equivalence principle, while the remaining terms that conserve probability also correspondingly satisfy the weak equivalence principle, at least to leading-order in the particle's Compton wavelength. Furthermore, this propagator possesses an overall curvature-dependent and gauge-invariant phase factor that can be interpreted as the gravitational Aharonov-Bohm effect and Berry's phase.Comment: 14 pages, 1 figure; major additions and revisions introduced; main conclusions are unchanged; new affiliation adde

The Lick-Carnegie Exoplanet Survey: A Saturn-Mass Planet in the Habitable Zone of the Nearby M4V Star HIP 57050

Precision radial velocities from Keck/HIRES reveal a Saturn-mass planet orbiting the nearby M4V star HIP 57050. The planet has a minimum mass of 0.3 Jupiter-mass, an orbital period of 41.4 days, and an orbital eccentricity of 0.31. V-band photometry reveals a clear stellar rotation signature of the host star with a period of 98 days, well separated from the period of the radial velocity variations and reinforcing a Keplerian origin for the observed velocity variations. The orbital period of this planet corresponds to an orbit in the habitable zone of HIP 57050, with an expected planetary temperature of approximately 230 K. The star has a metallicity of [Fe/H] = 0.32+/-0.06 dex, of order twice solar and among the highest metallicity stars in the immediate solar neighborhood. This newly discovered planet provides further support that the well-known planet-metallicity correlation for F, G, and K stars also extends down into the M-dwarf regime. The a priori geometric probability for transits of this planet is only about 1%. However, the expected eclipse depth is ~7%, considerably larger than that yet observed for any transiting planet. Though long on the odds, such a transit is worth pursuing as it would allow for high quality studies of the atmosphere via transmission spectroscopy with HST. At the expected planetary effective temperature, the atmosphere may contain water clouds.Comment: 20 pages, 5 figures, 3 tables, to appear in the May 20 issue of ApJ

Avoiding metallic walls: Use of modal superposition in plasmonic waveguides to reduce propagation loss

We theoretically explore the possibility of reducing the propagation loss in a metal-insulator-metal (MIM) waveguide, using mode combinations to achieve wall-avoiding field distributions along a certain propagation length. We present analytical results for several waveguides showing notable loss reduction, and we discuss the tradeoffs between low loss and high confinement present in this technique

The Dutch version of the Child Posttraumatic Cognitions Inventory:validation in a clinical sample and a school sample

With the inclusion of trauma-related cognitions in the DSM-5 criteria for posttraumatic stress disorder (PTSD), the assessment of these cognitions has become essential. Therefore, valid tools for the assessment of these cognitions are warranted

Dynamical Theory of Artificial Optical Magnetism Produced by Rings of Plasmonic Nanoparticles

We present a detailed analytical theory for the plasmonic nanoring configuration first proposed in [A. Alu, A. Salandrino, N. Engheta, Opt. Expr. 14, 1557 (2006)], which is shown to provide negative magnetic permeability and negative index of refraction at infrared and optical frequencies. We show analytically how the nanoring configuration may provide superior performance when compared to some other solutions for optical negative index materials, offering a more 'pure' magnetic response at these high frequencies, which is necessary for lowering the effects of radiation losses and absorption. Sensitivity to losses and the bandwidth of operation of this magnetic inclusion are also investigated in details and compared with other available setups.Comment: 34 pages, 3 figure

Lp-cohomology of negatively curved manifolds

We compute the $L^p$-cohomology spaces of some negatively curved manifolds. We deal with two cases: manifolds with finite volume and sufficiently pinched negative curvature, and conformally compact manifolds

The Association of NOV/CCN3 With Obstructive Sleep Apnea (OSA): Preliminary Evidence of a Novel Biomarker in OSA

Obstructive sleep apnea (OSA) has a strong association with cardiovascular and metabolic abnormalities, although the mechanism driving this association is not well established. NOV/CCN3, a multifunctional extracellular matrix protein, may play a mechanistic and/or prognostic role in these associations. We hypothesized that patients with OSA, which primarily affects obese individuals, will have increased levels of NOV, and that NOV can serve as a biomarker in patients to predict OSA as well as metabolic and cardiac risk. Ten morbidly obese and 10 healthy lean subjects underwent overnight polysomnography (PSG) and clinical evaluation. Blood samples were analyzed for NOV levels, adiponectin and IL-6. OSA was found in nine obese subjects and three lean subjects. NOV levels were significantly higher in the OSA vs. no OSA group (2.1 +/- 0.9 vs. 1.3 +/- 0.8, p \u3c 0.03). NOV levels were significantly higher in the obese vs. lean group (2.2 +/- 0.3 vs. 1.4 +/- 0.2-fold change, p \u3c 0.03). Among lean subjects, NOV levels were significantly higher in the OSA vs. no OSA group (2.1 +/- 0.9 vs. 1.0 +/- 0.4, p \u3c 0.05). NOV and AHI were positively correlated (rho = 0.49, p = 0.033). IL-6 and adiponectin differences in obese vs. lean and OSA vs. no OSA were consistent with an inflammatory phenotype in obese subjects and OSA subjects. NOV is a novel biomarker of the presence and severity of OSA and a potential marker of future cardiovascular and metabolic disease in OSA patients

Can Gravity Distinguish Between Dirac and Majorana Neutrinos?

We show that spin-gravity interaction can distinguish between Dirac and Majorana neutrino wave packets propagating in a Lense-Thirring background. Using time-independent perturbation theory and gravitational phase to generate a perturbation Hamiltonian with spin-gravity coupling, we show that the associated matrix element for the Majorana neutrino differs significantly from its Dirac counterpart. This difference can be demonstrated through significant gravitational corrections to the neutrino oscillation length for a two-flavour system, as shown explicitly for SN1987A.Comment: 4 pages, 2 figures; minor changes of text; typo corrected; accepted in Physical Review Letter