Neutrino telescope modelling of Lorentz invariance violation in oscillations of atmospheric neutrinos

One possible feature of quantum gravity may be the violation of Lorentz invariance. In this paper, we consider one particular manifestation of the violation of Lorentz invariance, namely modified dispersion relations for massive neutrinos. We show how such modified dispersion relations may affect atmospheric neutrino oscillations. We then consider how neutrino telescopes, such as ANTARES, may be able to place bounds on the magnitude of this type of Lorentz invariance violation

Quantum Decoherence in a Four-Dimensional Black Hole Background

We display a logarithmic divergence in the density matrix of a scalar field in the presence of an Einstein-Yang-Mills black hole in four dimensions. This divergence is related to a previously-found logarithmic divergence in the entropy of the scalar field, which cannot be absorbed into a renormalization of the Hawking-Bekenstein entropy of the black hole. As the latter decays, the logarithmic divergence induces a non-commutator term \nd{\delta H}\rho in the quantum Liouville equation for the density matrix $\rho$ of the scalar field, leading to quantum decoherence. The order of magnitude of \nd{\delta H} is $\mu^2/M_P$, where $\mu$ is the mass of the scalar particle.Comment: 13-pages LATE

Comparison of mercury in atmospheric deposition and in Illinois and USA soils

International audienceIt has been reported that most mercury (Hg) in USA soils is from atmospheric Hg deposition, mostly from anthropogenic sources. This paper compares the rates of atmospheric Hg deposition to amounts of Hg in Illinois and USA soils. The amounts of Hg in these soils are too great to be attributed mainly to anthropogenic atmospheric Hg deposition. Keywords: mercury, atmospheric deposition, soil, geology, Illinois, US

A descriptive literature review of Recognition of Prior Learning for vocational learners in emergency medical care in South Africa

Radical advances in emergency medical care education in South Africa have resulted in both advancements and suppression. After short-course vocational training, the emergency care provider could seek employment in an emergency service. With the realignment of emergency medical care programmes to the National Qualifications Framework (NQF), these short vocational courses were phased out by 2018. Although necessary for educational advancement, these changes prevented vocationally trained emergency care providers from articulating into higher education without returning to full-time academia. Moreover, despite recognition of prior learning (RPL) policies in higher education, few institutes offering emergency medical care programmes offered this as an access option. This descriptive literature review aimed to analyse the RPL processes in South Africa and globally. Additionally, insight into RPL candidates” support requirements for postgraduate studies was gained. A systematic search of peer-reviewed journal articles, periodicals, dissertations, and governmental reports from 2000 to 2021 was conducted. Various databases were accessed, including Proquest, EBSCOhost, LearnTechLib, JSTOR, ERIC, Google Scholar, and the Thesis Repository. The lack of literature focusing on the prehospital RPL system in South Africa prompted search expansions into the field of health science internationally. Of the 401 screened sources, 19 met the researcher’s inclusion criteria. Two additional articles were sourced in a repeated search in February 2022. The findings revealed enablers and barriers for RPL students and expanded on their personal and academic transitions. The themes identified through the enablers and barriers can assist in identifying additional support for RPL students during their educational journey. Ultimately, despite vital institutional transitions in RPL processes, intrinsic motivation inspired these students to embrace the challenges they faced, and their process of personal transition and lifelong learning began

Characterizing asymptotically anti-de Sitter black holes with abundant stable gauge field hair

In the light of the "no-hair" conjecture, we revisit stable black holes in su(N) Einstein-Yang-Mills theory with a negative cosmological constant. These black holes are endowed with copious amounts of gauge field hair, and we address the question of whether these black holes can be uniquely characterized by their mass and a set of global non-Abelian charges defined far from the black hole. For the su(3) case, we present numerical evidence that stable black hole configurations are fixed by their mass and two non-Abelian charges. For general N, we argue that the mass and N-1 non-Abelian charges are sufficient to characterize large stable black holes, in keeping with the spirit of the "no-hair" conjecture, at least in the limit of very large magnitude cosmological constant and for a subspace containing stable black holes (and possibly some unstable ones as well).Comment: 33 pages, 13 figures, minor change

Geon black holes and quantum field theory

Black hole spacetimes that are topological geons in the sense of Sorkin can be constructed by taking a quotient of a stationary black hole that has a bifurcate Killing horizon. We discuss the geometric properties of these geon black holes and the Hawking-Unruh effect on them. We in particular show how correlations in the Hawking-Unruh effect reveal to an exterior observer features of the geometry that are classically confined to the regions behind the horizons.Comment: 11 pages. Talk given at the First Mediterranean Conference on Classical and Quantum Gravity, Kolymbari (Crete, Greece), September 2009. Dedicated to Rafael Sorkin. v2: typesetting bug fixe

Probing quantum decoherence in atmospheric neutrino oscillations with a neutrino telescope

Quantum decoherence, the evolution of pure states into mixed states, may be a feature of quantum gravity. In this paper, we show how these effects can be modelled for atmospheric neutrinos and illustrate how the standard oscillation picture is modified. We examine how neutrino telescopes, such as ANTARES, are able to place upper bounds on these quantum decoherence effects

Case Study: Cancrum oris (noma) in a malnourished HIV-positive child from rural Kwazulu-Natal

Cancrum oris (noma – derived from the Greek nomein, ‘to devour\') is an infectious disease with a fulminating course that destroys the oro-facial tissues and other neighbouring structures.1 Although cancrum oris can occur at any age, it is most commonly in malnourished children between the ages of 1 and 5 years whose general health has been further weakened by some infectious disease, usually measles but also tuberculosis, gastro-enteritis, typhoid, whooping cough, or malignant disease such as leukaemia. The possible relevance to HIV has not been fully investigated. This report details a case presenting to East Griqualand and Usher Memorial Hospital, Kokstad, KwaZulu-Natal. Southern African Journal of HIV Medicine Vol. 5 (3) 2004: 45-4

Decoherent Scattering of Light Particles in a D-Brane Background

We discuss the scattering of two light particles in a D-brane background. It is known that, if one light particle strikes the D brane at small impact parameter, quantum recoil effects induce entanglement entropy in both the excited D brane and the scattered particle. In this paper we compute the asymptotic `out' state of a second light particle scattering off the D brane at large impact parameter, showing that it also becomes mixed as a consequence of quantum D-brane recoil effects. We interpret this as a non-factorizing contribution to the superscattering operator S-dollar for the two light particles in a Liouville D-brane background, that appears when quantum D-brane excitations are taken into account.Comment: 18 pages LATEX, one figure (incorporated

Instability of a four-dimensional de Sitter black hole with a conformally coupled scalar field

We study the stability of new neutral and electrically charged four-dimensional black hole solutions of Einstein's equations with a positive cosmological constant and conformally coupled scalar field. The neutral black holes are always unstable. The charged black holes are also shown analytically to be unstable for the vast majority of the parameter space of solutions, and we argue using numerical techniques that the configurations corresponding to the remainder of the parameter space are also unstable.Comment: revtex4, 8 pages, 4 figures, minor changes, accepted for publication in Phys. Rev.