Characterization of some causality conditions through the continuity of the Lorentzian distance

A classical result in Lorentzian geometry states that a strongly causal spacetime is globally hyperbolic if and only if the Lorentzian distance is finite valued for every metric choice in the conformal class. It is proven here that a non-total imprisoning spacetime is globally hyperbolic if and only if for every metric choice in the conformal class the Lorentzian distance is continuous. Moreover, it is proven that a non-total imprisoning spacetime is causally simple if and only if for every metric choice in the conformal class the Lorentzian distance is continuous wherever it vanishes. Finally, a strongly causal spacetime is causally continuous if and only if there is at least one metric in the conformal class such that the Lorentzian distance is continuous wherever it vanishes.Comment: 14 pages, 2 figure. v2: Added material on global hyperbolicity. The title has changed. Previous title: Characterization of causal simplicity and causal continuity through the continuity of the Lorentzian distance. v3: Some misprints fixed. Final versio

Argyres-Douglas Theories in Class S Without Irregularity

We make a preliminary investigation into twisted $A_{2n}$ theories of class S. Contrary to a common piece of folklore, we establish that theories of this type realise a variety of models of Argyres-Douglas type while utilising only regular punctures. We present an in-depth analysis of all twisted $A_2$ trinion theories, analyse their interrelations via partial Higgsing, and discuss some of their generalised S-dualities.Comment: 37 page

Wireless Node Cooperation with Resource Availability Constraints

Base station cooperation is a promising scheme to improve network performance for next generation cellular networks. Up to this point research has focused on station grouping criteria based solely on geographic proximity. However, for the cooperation to be meaningful, each station participating in a group should have sufficient available resources to share with others. In this work we consider an alternative grouping criterion based on a distance that considers both geographic proximity and available resources of the stations. When the network is modelled by a Poisson Point Process, we derive analytical formulas on the proportion of cooperative pairs or single stations, and the expected sum interference from each of the groups. The results illustrate that cooperation gains strongly depend on the distribution of available resources over the network.Comment: submitted, 12 pages, double-column, 7 figures, 8 sub-figures in tota

Curvature of Multiply Warped Products

In this paper, we study Ricci-flat and Einstein Lorentzian multiply warped products. We also consider the case of having constant scalar curvatures for this class of warped products. Finally, after we introduce a new class of spacetimes called as generalized Kasner space-times, we apply our results to this kind of space-times as well as other relativistic space-times, i.e., Reissner-Nordstrom, Kasner space-times, Banados-Teitelboim-Zanelli and de Sitter Black hole solutions.Comment: 28 pages, corrected typos, to appear in Journal of Geometry and Physic

AdS/CFT Dual Pairs from M5-Branes on Riemann Surfaces

In this letter we describe an infinite family of new N=1 AdS_5/CFT_4 dual pairs which arise from M5-branes wrapping Riemann surfaces in Calabi-Yau threefolds. We use the relevant brane constructions to compute the central charges of the infrared fixed points from the M5-brane anomaly polynomial. We then present AdS_5 x M_6 solutions of eleven-dimensional supergravity which are dual to these CFTs at large N. Finally, we provide a purely four-dimensional field theory construction which flows to a special class of these fixed points. These theories will be further elaborated upon in a companion paper.Comment: 4 pages, 2 figures. v2: typos corrected, conclusions section omitted for lengt

Rainbow Trout Culture in South Dakota

On a lettuce leaf with a twist of lemon, you can’t tell a “wild” trout from a good commercial fish farm rainbow. Demand for trout far exceeds supply, and most South Dakotans will settle gratefully for a commercially raised rainbow. There are customers out there if you are thinking of adding a commercial trout enterprise to your farming or ranching operation. This Extra provides information about raising trout in existing ponds and lakes in South Dakota. Trout culture in many areas of the state is new, therefore research from other states is the basis for much of the information in this Extra

French and Fashionable

Toni Miley, after spending 14 months in France, saw her exaggerated ideas of French creations take a nosedive when she discovered the aver.age French woman\u27s taste in clothes. Paris- home of the world-famous fashion designers- has even felt a modified influence of the Davy Crockett coonskin cap! A typical example was the old French woman who used the familiar cap with its tail hanging down the back to dress up her raccoon coat

Choose Wisely, Cutlery

Cutting, paring, slicing, chopping. Most food preparation involves these essential procedures. With this in mind, let\u27s take an imaginary shopping trip to buy those s peci ally designed pieces of cutlery needed in the kitchen