On the existence of dyons and dyonic black holes in Einstein-Yang-Mills theory

We study dyonic soliton and black hole solutions of the ${\mathfrak {su}}(2)$ Einstein-Yang-Mills equations in asymptotically anti-de Sitter space. We prove the existence of non-trivial dyonic soliton and black hole solutions in a neighbourhood of the trivial solution. For these solutions the magnetic gauge field function has no zeros and we conjecture that at least some of these non-trivial solutions will be stable. The global existence proof uses local existence results and a non-linear perturbation argument based on the (Banach space) implicit function theorem.Comment: 23 pages, 2 figures. Minor revisions; references adde

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

Data Fusion for Topographic Object Classification

This paper presents research conducted into the automatic recognition of features and objects on topographic maps (for example, buildings, roads, land parcels etc.) using a selection of shape description methods developed mostly in the field of computer vision. In particular the work here focuses on the proposal and evaluation of fusion techniques (at the decision level of representation) for the classification of topographic data. A set of Ordnance Survey large-scale digital data (1:1250 and 1:2500) was used to evaluate the classification performance of the shape recognition methods used. Each technique proved partially successful in distinguishing classes of objects, however, no one technique provided a general solution to the problem. Further outlined experiments combine these techniques, using a data fusion methodology, on the real-world problem of checking and assigning feature codes in large-scale Ordnance Survey digital data

Lorentz and CPT Invariance Violation In High-Energy Neutrinos

High-energy neutrino astronomy will be capable of observing particles at both extremely high energies and over extremely long baselines. These features make such experiments highly sensitive to the effects of CPT and Lorentz violation. In this article, we review the theoretical foundation and motivation for CPT and Lorentz violating effects, and then go on to discuss the related phenomenology within the neutrino sector. We describe several signatures which might be used to identify the presence of CPT or Lorentz violation in next generation neutrino telescopes and cosmic ray experiments. In many cases, high-energy neutrino experiments can test for CPT and Lorentz violation effects with much greater precision than other techniques.Comment: 27 pages, 8 figure

Comparison of radiation safety and nuclear explosive safety disciplines

In August 1945, U.S. Navy Captain William Parsons served as the weaponeer aboard the Enola Gay for the mission to Hiroshima (Shelton 1988). In view of the fact that four B-29s had crashed and burned on takeoff from Tinian the night before, Captain Parsons made the decision to arm the gun-type weapon after takeoff for safety reasons (15 kilotons of TNT equivalent). Although he had no control over the success of the takeoff, he could prevent the possibility of a nuclear detonation on Tinian by controlling what we now call the nuclear explosive. As head of the Ordnance Division at Los Alamos and a former gunnery officer, Captain Parsons clearly understood the role of safety in his work. The advent of the pre-assembled implosion weapon where the high explosive and nuclear materials are always in an intimate configuration meant that nuclear explosive safety became a reality at a certain point in development and production not just at the time of delivery by the military. This is the only industry where nuclear materials are intentionally put in contact with high explosives. The agency of the U.S. Government responsible for development and production of U.S. nuclear weapons is the Department of Energy (DOE) (and its predecessor agencies). This paper will be limited to nuclear explosive safety as it is currently practiced within the DOE nuclear weapon

Studies on the effect on root growth of continued rotation about a horizontal axis

An attempt has been made to discover whether or not the growth rate of roots rotated about a horizontal axis is affected by the speed at which the rotation occurs. The method entailed a double selection of the roots to ensure that all the roots used in each experiment were straight and of equal initial length. Pea roots were used and the seedlings were intact throughout the experiment. The roots were held horizontally in jars which were supported in horizontal cradles. These cradles were attached to rotary spindles driven electrically and connected by driving chain to a geared klinostat so that their rotary speeds could be varied. The whole apparatus was enclosed in a box from which the light was excluded. The roots were photographed every half hour through a vertical slit in the wall of the box, a light being switched on momentarily inside while the exposure was made. The negatives were developed and the roots at successive half hourly intervals were measured from these negatives with a travelling microscope. The increases in length and hence the growth rates were calculable. This was repeated at various speeds. Graphs of growth rate against time have been plotted. Correlation coefficients have been calculated for growth rate on time and regression lines have been drawn. Some statistical analyses have also been done. There appears to be no well defined effect of speed of rotation on growth rate although rotated roots seemed to have a lower growth rate than vertical non-rotated roots and, in general, the slower the speed of rotation the lower the growth rate. Time does seem to affect the growth rate trend and appears to have most effect when the growth rate is generally high and also when the speed of rotation is high. N.B. Figures 1-8 will be found in the text and Figures 9 - 25 will be found in the Appendix

Dyons and dyonic black holes in su(N){\mathfrak {su}}(N) Einstein-Yang-Mills theory in anti-de Sitter space-time

We present new spherically symmetric, dyonic soliton and black hole solutions of the ${\mathfrak {su}}(N)$ Einstein-Yang-Mills equations in four-dimensional asymptotically anti-de Sitter space-time. The gauge field has nontrivial electric and magnetic components and is described by $N-1$ magnetic gauge field functions and $N-1$ electric gauge field functions. We explore the phase space of solutions in detail for ${\mathfrak {su}}(2)$ and ${\mathfrak {su}}(3)$ gauge groups. Combinations of the electric gauge field functions are monotonic and have no zeros; in general the magnetic gauge field functions may have zeros. The phase space of solutions is extremely rich, and we find solutions in which the magnetic gauge field functions have more than fifty zeros. Of particular interest are solutions for which the magnetic gauge field functions have no zeros, which exist when the negative cosmological constant has sufficiently large magnitude. We conjecture that at least some of these nodeless solutions may be stable under linear, spherically symmetric, perturbations

Low cancer suspicion following experience of a cancer 'warning sign'

© 2015 The Authors. Published by Elsevier Ltd. Aim Lower socioeconomic status (SES) is associated with a higher risk of late-stage cancer diagnosis. A number of explanations have been advanced for this, but one which has attracted recent attention is lower patient knowledge of cancer warning signs, leading to delay in help-seeking. However, although there is psychometric evidence of SES differences in knowledge of cancer symptoms, no studies have examined differences in 'cancer suspicion' among people who are actually experiencing a classic warning sign. Methods A 'health survey' was mailed to 9771 adults (≥50 years, no cancer diagnosis) with a symptom list including 10 cancer 'warning signs'. Respondents were asked if they had experienced any of the symptoms in the past 3 months, and if so, were asked 'what do you think caused it?' Any mention of cancer was scored as 'cancer suspicion'. SES was indexed by education. Results Nearly half the respondents (1732/3756) had experienced a 'warning sign', but only 63/1732 (3.6%) mentioned cancer as a possible cause. Lower education was associated with lower likelihood of cancer suspicion: 2.6% of respondents with school-only education versus 7.3% with university education suspected cancer as a possible cause. In multivariable analysis, low education was the only demographic variable independently associated with lower cancer suspicion (odds ratio (OR) = 0.34, confidence interval (CI): 0.20-0.59). Conclusion Levels of cancer suspicion were low overall in this community sample, and even lower in people from less educated backgrounds. This may hinder early symptomatic presentation and contribute to inequalities in stage at diagnosis