Added Value of Teaching in a Virtual World
DEFF Research Database (Denmark)
Christensen, Inger-Marie F.; Marunchak, Andrew; Stefanelli, Cristina
2013-01-01
This chapter discusses the educational potential of virtual worlds and the challenges faced when using them to facilitate communication and learning. Virtual worlds can be a valid means of engaging with and motivating younger audiences in today’s digital culture. They provide an authentic context...... in which students can participate in meaningful learning activities. The conclusion states that innovation is needed to successfully implement virtual world learning and technology into the classroom. Variables to be considered when embarking on educational design using virtual worlds involve the use...
Using Real-World Car Traffic Dataset in Vehicular Ad Hoc Network Performance Evaluation
Directory of Open Access Journals (Sweden)
Lucas Rivoirard
2016-12-01
Full Text Available Vehicular ad hoc networking is an emerging paradigm which is gaining much interest with the development of new topics such as the connected vehicle, the autonomous vehicle, and also new high-speed mobile communication technologies such as 802.11p and LTE-D. This paper presents a brief review of different mobility models used for evaluating performance of routing protocols and applications designed for vehicular ad hoc networks. Particularly, it describes how accurate mobility traces can be built from a real-world car traffic dataset that embeds the main characteristics affecting vehicle-to-vehicle communications. An effective use of the proposed mobility models is illustrated in various road traffic conditions involving communicating vehicles equipped with 802.11p. This study shows that such dataset actually contains additional information that cannot completely be obtained with other analytical or simulated mobility models, while impacting the results of performance evaluation in vehicular ad hoc networks.
Castanea sativa by-products: a review on added value and sustainable application.
Braga, Nair; Rodrigues, Francisca; Oliveira, M Beatriz P P
2015-01-01
Castanea sativa Mill. is a species of the family Fagaceae abundant in south Europe and Asia. The fruits (chestnut) are an added value resource in producing countries. Chestnut economic value is increasing not only for nutritional qualities but also for the beneficial health effects related with its consumption. During chestnut processing, a large amount of waste material is generated namely inner shell, outer shell and leaves. Studies on chestnut by-products revealed a good profile of bioactive compounds with antioxidant, anticarcinogenic and cardioprotective properties. These agro-industrial wastes, after valorisation, can be used by other industries, such as pharmaceutical, food or cosmetics, generating more profits, reducing pollution costs and improving social, economic and environmental sustainability. The purpose of this review is to provide knowledge about the type of chestnut by-products produced, the studies concerning its chemical composition and biological activity, and also to discuss other possible applications of these materials.
The Microbase Value-Added Product: A Baseline Retrieval of Cloud Microphysical Properties
Energy Technology Data Exchange (ETDEWEB)
Dunn, M; Johnson, K; Jensen, M
2011-05-31
This report describes the Atmospheric Radiation Measurement (ARM) Climate Research Facility baseline cloud microphysical properties (MICROBASE) value-added product (VAP). MICROBASE uses a combination of millimeter-wavelength cloud radar, microwave radiometer, and radiosonde observations to estimate the vertical profiles of the primary microphysical parameters of clouds including the liquid/ice water content and liquid/ice cloud particle effective radius. MICROBASE is a baseline algorithm designed to apply to most conditions and locations using a single set of parameterizations and a simple determination of water phase based on temperature. This document provides the user of this product with guidelines to assist in determining the accuracy of the product under certain conditions. Quality control flags are designed to identify outliers and indicate instances where the retrieval assumptions may not be met. The overall methodology is described in this report through a detailed description of the input variables, algorithms, and output products.
Biotransformation of lignocellulosic materials into value-added products-A review.
Bilal, Muhammad; Asgher, Muhammad; Iqbal, Hafiz M N; Hu, Hongbo; Zhang, Xuehong
2017-02-03
In the past decade, with the key biotechnological advancements, lignocellulosic materials have gained a particular importance. In serious consideration of global economic, environmental and energy issues, research scientists have been re-directing their interests in (re)-valorizing naturally occurring lignocellulosic-based materials. In this context, lignin-modifying enzymes (LMEs) have gained considerable attention in numerous industrial and biotechnological processes. However, their lower catalytic efficiencies and operational stabilities limit their practical and multipurpose applications in various sectors. Therefore, to expand the range of natural industrial biocatalysts e.g. LMEs, significant progress related to the enzyme biotechnology has appeared. Owing to the abundant lignocellulose availability along with LMEs in combination with the scientific advances in the biotechnological era, solid-phase biocatalysts can be economically tailored on a large scale. This review article outlines first briefly on the lignocellulose materials as a potential source for biotransformation into value-added products including composites, fine chemicals, nutraceutical, delignification, and enzymes. Comprehensive information is also given on the purification and characterization of LMEs to present their potential for the industrial and biotechnological sector.
A Self-Organization Framework for Wireless Ad Hoc Networks as Small Worlds
Banerjee, Abhik; Gauthier, Vincent; Yeo, Chai Kiat; Afifi, Hossam; Lee, Bu Sung
2012-01-01
Motivated by the benefits of small world networks, we propose a self-organization framework for wireless ad hoc networks. We investigate the use of directional beamforming for creating long-range short cuts between nodes. Using simulation results for randomized beamforming as a guideline, we identify crucial design issues for algorithm design. Our results show that, while significant path length reduction is achievable, this is accompanied by the problem of asymmetric paths between nodes. Subsequently, we propose a distributed algorithm for small world creation that achieves path length reduction while maintaining connectivity. We define a new centrality measure that estimates the structural importance of nodes based on traffic flow in the network, which is used to identify the optimum nodes for beamforming. We show, using simulations, that this leads to significant reduction in path length while maintaining connectivity.
Directed Dynamic Small-World Network Model for Worm Epidemics in Mobile ad hoc Networks
Institute of Scientific and Technical Information of China (English)
ZHU Chen-Ping; WANG Li; LIU Xiao-Ting; YAN Zhi-Jun
2012-01-01
We investigate the worm spreading process in mobile ad hoc networks with a susceptible-infected-recovered model on a two-dimensional plane.A medium access control mechanism operates within it,inhibiting transmission and relaying a message by using other nodes inside the node's transmitting circle during speaking.We measure the rewiring probability p with the transmitting range r and the average relative velocity (v) of the moving nodes,and map the problem into a directed dynamic small-world network.A new scaling relation for the recovered portion of the nodes reveals the effect caused by geometric distance,which has been ignored by previous models.%We investigate the worm spreading process in mobile ad hoc networks with a susceptible-infected-recovered model on a two-dimensional plane. A medium access control mechanism operates within it, inhibiting transmission and relaying a message by using other nodes inside the node's transmitting circle during speaking. We measure the rewiring probability p with the transmitting range r and the average relative velocity (v) of the moving nodes, and map the problem into a directed dynamic small-world network. A new scaling relation for the recovered portion of the nodes reveals the effect caused by geometric distance, which has been ignored by previous models.
Institute of Scientific and Technical Information of China (English)
无
2006-01-01
In this paper, we introduce a modified small-world network added with new links with preferential connection instead of adding randomly, then we apply Bak-Sneppen (BS) evolution model on this network. Several dynamical character of the model such as the evolution graph, fo avalanche, the critical exponent D and τ, and the distribution of mutation times of all the nodes, show particular behaviors different from those of the model based on the regular network and the small-world network.
Power Polarity In The Far Eastern World System, 1025 BCAD 1850: Narrative And 25-Year Interval Data
Directory of Open Access Journals (Sweden)
David Wikinson
2015-08-01
Full Text Available Power polarity in the Far Eastern macro-social system is assessed at twenty five year intervals 1050 BC-AD 1850. Consistent with analysis of Indic system data, there is no support for the theory that the normal world-system power configuration is multipolar, hegemonic, or universal-empire. Instead several different "stability epochs" are discerned.
Transnational Corporations in a Global Monetary Theory of Production: A World-Systems Perspective
Directory of Open Access Journals (Sweden)
Marc Pilkington
2015-08-01
Full Text Available In this paper, I argue that it is possible to enrich world-systems analysis with a heterodox Keynesian monetary theory of production known as the Theory of Money Emissions, based on the views put forward by the French economist Bernard Schmitt. In the aftermath of the global financial crisis, I aim to rehabilitate and adapt the old Keynesian proposal of an international clearing union to the modern world-system by providing a rationale behind a common world currency and a renewed perspective on money and transnational production.
Directory of Open Access Journals (Sweden)
Christian Ginzler
2012-05-01
Full Text Available Digital surface models (DSMs are widely used in forest science to model the forest canopy. Stereo pairs of very high resolution satellite and digital aerial images are relatively new and their absolute accuracy for DSM generation is largely unknown. For an assessment of these input data two DSMs based on a WorldView-2 stereo pair and a ADS80 DSM were generated with photogrammetric instruments. Rational polynomial coefficients (RPCs are defining the orientation of the WorldView-2 satellite images, which can be enhanced with ground control points (GCPs. Thus two WorldView-2 DSMs were distinguished: a WorldView-2 RPCs-only DSM and a WorldView-2 GCP-enhanced RPCs DSM. The accuracy of the three DSMs was estimated with GPS measurements, manual stereo-measurements, and airborne laser scanning data (ALS. With GCP-enhanced RPCs the WorldView-2 image orientation could be optimised to a root mean square error (RMSE of 0.56 m in planimetry and 0.32 m in height. This improvement in orientation allowed for a vertical median error of −0.24 m for the WorldView-2 GCP-enhanced RPCs DSM in flat terrain. Overall, the DSM based on ADS80 images showed the highest accuracy of the three models with a median error of 0.08 m over bare ground. As the accuracy of a DSM varies with land cover three classes were distinguished: herb and grass, forests, and artificial areas. The study suggested the ADS80 DSM to best model actual surface height in all three land cover classes, with median errors < 1.1 m. The WorldView-2 GCP-enhanced RPCs model achieved good accuracy, too, with median errors of −0.43 m for the herb and grass vegetation and −0.26 m for artificial areas. Forested areas emerged as the most difficult land cover type for height modelling; still, with median errors of −1.85 m for the WorldView-2 GCP-enhanced RPCs model and −1.12 m for the ADS80 model, the input data sets evaluated here are quite promising for forest canopy modelling.
Institute of Scientific and Technical Information of China (English)
ZHANG Ying-Yue; YANG Qiu-Ying; CHEN Tian-Lun
2007-01-01
We introduce a modified small-world network adding new links with nonlinearly preferential connection instead of adding randomly, then we apply Bak-Sneppen (BS) evolution model on this network. We study several important structural properties of our network such as the distribution of link-degree, the maximum link-degree, and the length of the shortest path. We further argue several dynamical characteristics of the model such as the important critical value fc, the f0 avalanche, and the mutating condition, and find that those characteristics show particular behaviors.
Directory of Open Access Journals (Sweden)
Eleni M W Maunder
Full Text Available The objective of this study was to determine the relationship between added sugar and dietary diversity, micronutrient intakes and anthropometric status in a nationally representative study of children, 1-8.9 years of age in South Africa.Secondary analysis of a national survey of children (weighted n = 2,200; non weighted n = 2818 was undertaken. Validated 24-hour recalls of children were collected from mothers/caregivers and stratified into quartiles of percentage energy from added sugar (% EAS. A dietary diversity score (DDS using 9 food groups, a food variety score (FVS of individual food items, and a mean adequacy ratio (MAR based on 11 micronutrients were calculated. The prevalence of stunting and overweight/obesity was also determined.Added sugar intake varied from 7.5-10.3% of energy intake for rural and urban areas, respectively. Mean added sugar intake ranged from 1.0% of energy intake in Quartile 1 (1-3 years (Q1 to 19.3% in Q4 (4-8 years. Main sources of added sugar were white sugar (60.1%, cool drinks (squash type (10.4% and carbonated cool drinks (6.0%. Added sugar intake, correlated positively with most micronutrient intakes, DDS, FVS, and MAR. Significant negative partial correlations, adjusted for energy intake, were found between added sugar intake and intakes of protein, fibre, thiamin, pantothenic acid, biotin, vitamin E, calcium (1-3 years, phosphorus, iron (4-8 years, magnesium and zinc. The prevalence of overweight/obesity was higher in children aged 4-8 years in Q4 of %EAS than in other quartiles [mean (95%CI % prevalence overweight 23.0 (16.2-29.8% in Q4 compared to 13.0 (8.7-17.3% in Q1, p = 0.0063].Although DDS, FVS, MAR and micronutrient intakes were positively correlated with added sugar intakes, overall negative associations between micronutrients and added sugar intakes, adjusted for dietary energy, indicate micronutrient dilution. Overweight/obesity was increased with higher added sugar intakes in the 4-8 year old
Self-Organization of Wireless Ad Hoc Networks as Small Worlds Using Long Range Directional Beams
Banerjee, Abhik; Gauthier, Vincent; Yeo, Chai Kiat; Afifi, Hossam; Lee, Bu Sung
2011-01-01
We study how long range directional beams can be used for self-organization of a wireless network to exhibit small world properties. Using simulation results for randomized beamforming as a guideline, we identify crucial design issues for algorithm design. Subsequently, we propose an algorithm for deterministic creation of small worlds. We define a new centrality measure that estimates the structural importance of nodes based on traffic flow in the network, which is used to identify the optimum nodes for beamforming. This results in significant reduction in path length while maintaining connectivity.
Trilateral Wadden Sea World Heritage Foundation, Exploring added value, strategy and organisation
During, R.; Coninx, I.; Simeonova, V.
2014-01-01
Once the Danish part of the Wadden Sea has been accepted for the UNESCO World Heritage List (expected in 2014), the whole of the Wadden Sea will then be enlisted and this offers new opportunities and obligations for integrative and integral management to safeguard its Outstanding Universal Value. Ac
Chemical Composition of Date-Pits and Its Potential for Developing Value-Added Product - a Review
Directory of Open Access Journals (Sweden)
Hossain Mohammad Zakir
2014-12-01
Full Text Available Moisture, protein, oil and carbohydrate contents of date-pits varied from 3.1-12.5, 2.3-6.9, 5.0-12.5 and 70.9-86.9 g/100 g date-pits, respectively. BET-monolayer (i.e. strongly bound moisture content, solids-melting peak (at moisture: 6.7 g/100 g date-pits, and melting point of oil were 4.3 g/100 g dry-solids, 106oC, and 1.8oC, respectively. The major fatty acids were lauric, myristic, palmitic, stearic, oleic, and linoleic acids and polyphenol content varied from 21.0-62.0 mg/g date-pits depending on the varieties, types of solvent and temperature used for extraction. Date-pits showed effectives in animal and poultry feeds and it could be used as value added products, such as: dietary fibres, functional polysaccharides, caffeine-free drinks (similar to coffee, oil (biofuel or cooking oil, and other functional or medicinal products. Date-pits powder and activated carbon from date–pits showed effective in purifying water by removing different types of pollutants, such as heavy metals, boron, dyes, phenolic compounds, and pesticides. Date-pits also showed effective to be used as ingredient for composed, biomass, and fermentation processes.
European Cartography on the Eve of the Discoveries, Part 5: Ptolemy's Map of the World, A.D. 1478.
Danzer, Gerald A.
1992-01-01
Describes Ptolemy's map of the world. Discusses the idea of mapping the ecumene or known world. Lists Ptolemy's map making conventions still in use today including location of north at the top, 90 degrees latitude between the equator and each pole, and style of representing physical features. Emphasizes Ptolemy's view of the world as dynamic. (DK)
Danzer, Gerald A.
1991-01-01
Describes the second map printed in Europe which appeared in 1475. Provides background information that teachers to help students grasp the fundamental aspects of the map. Explores the map as a whole, its details and parts, and the significance of the map for studying the world view of Europeans preceding Columbus's discoveries. (DK)
Directory of Open Access Journals (Sweden)
George Pararas-Carayannis
2011-01-01
Full Text Available There is ample evidence indicating that on July 21, 365 AD a great earthquake near the west coast of the Island of Crete generated a mega-tsunami, which was responsible for extensive destruction throughout the Eastern Mediterranean, but particularly on Peloponnesus, the Greek Islands, Sicily, Libya, Cyprus, Palestine and Egypt. It is believed that the combined catastrophic impacts of the earthquake and tsunami were significant catalysts in furthering the declination of the Roman Empire and contributing to its subsequent final division between the East Roman and the West (Byzantine empires in 395 A.D. In view of subsequent earthquakes and tsunamis in the region and the high probability that a similar great disaster will occur again, the present study reviews and summarizes the seismo-tectonic and kinematic characteristics of the Aegean and Anatolian micro-plates, their interaction with the African and Eurasian tectonic plates and examines and evaluates the historical records pertaining to this 4th Century AD disaster as to the destructive impact it had on the ancient world. Additionally, the study reconciles the impact described in historical and recent records with results obtained by numerical modeling studies, provides a rough estimate of the recurrence frequency of great tsunamigenic earthquakes in the Eastern Mediterranean region and assesses what the future impact may be in view of great increases in population densities along coastal areas.
Directory of Open Access Journals (Sweden)
S. Pérez-Rodríguez
2011-01-01
Full Text Available Vulcan XC-72R-supported Fe catalysts have been synthesised for the electroreduction of CO2 to high-added value products. Catalysts were obtained by the polyol method, using ethylene glycol as solvent and reducing agent. Prior to the metal deposition, Vulcan was subjected to different oxidation treatments in order to modify its surface chemistry and study its influence on the physicochemical and electrochemical properties of the catalysts, as well as on the product distribution. The oxidation treatments of the supports modify their textural properties, but do not affect significantly the physicochemical properties of catalysts. However, DEMS studies showed that the carbon support degradation, the distribution of products, and the catalytic activity toward the CO2 electroreduction reaction depend significantly on the surface chemistry of the carbon support.
Motil, Susan M.; Ludwiczak, Damian R.; Carek, Gerald A.; Sorge, Richard N.; Free, James M.; Cikanek, Harry A., III
2011-01-01
NASA s human space exploration plans developed under the Exploration System Architecture Studies in 2005 included a Crew Exploration Vehicle launched on an Ares I launch vehicle. The mass of the Crew Exploration Vehicle and trajectory of the Ares I coupled with the need to be able to abort across a large percentage of the trajectory generated unprecedented testing requirements. A future lunar lander added to projected test requirements. In 2006, the basic test plan for Orion was developed. It included several types of environment tests typical of spacecraft development programs. These included thermal-vacuum, electromagnetic interference, mechanical vibration, and acoustic tests. Because of the size of the vehicle and unprecedented acoustics, NASA conducted an extensive assessment of options for testing, and as result, chose to augment the Space Power Facility at NASA Plum Brook Station, of the John H. Glenn Research Center to provide the needed test capabilities. The augmentation included designing and building the World s highest mass capable vibration table, the highest power large acoustic chamber, and adaptation of the existing World s largest thermal vacuum chamber as a reverberant electromagnetic interference test chamber. These augmentations were accomplished from 2007 through early 2011. Acceptance testing began in Spring 2011 and will be completed in the Fall of 2011. This paper provides an overview of the capabilities, design, construction and acceptance of this extraordinary facility.
Danzer, Gerald A.
1992-01-01
Describes a woodcut of the earliest map printed in a vernacular language, circa 1480. Discusses the location and representation of paradise, the winds, rivers, the world sea and islands, countries, and cities. Emphasizes the map as a world view of the late Middle Ages representing the popular culture of the time. (DK)
Zambrano, Andrea I.; Sharma, Shekhar; Crowley, Kathryn; Dize, Laura; Muñoz, Beatriz E.; Mishra, Sailesh K.; Rotondo, Lisa A.; Gaydos, Charlotte A.; West, Sheila K.
2016-01-01
Background The World Health Organization (WHO) now requires a second surveillance survey for trachoma after an impact assessment has found follicular trachoma (TF) <5% to determine if re-emergence has occurred. Using new WHO guidelines, we undertook surveillance surveys, and determined the prevalence of infection and antibody positivity, in two districts in Nepal. Methods 20 clusters were randomly selected within each district, 15 were randomly selected for antibody testing. In each cluster, we randomly selected 50 children ages 1–9 years and 100 adults ≥15 years. TF and trachomatous trichiasis (TT) were evaluated. Conjunctival swabs to test for chlamydial infection using GenXpert platform were obtained, and dried blood spots were collected to test for antibodies to Chlamydia Trachomatis pgp3 using the Luminex platform. Findings 3 cases of TF were found in the two districts, and one case of infection. Pgp3 antibody positivity was 2·4% (95% confidence interval: 1·4%, 3·7%), and did not increase with age (P = 0.24). No clustering of antibody positivity within communities was found. TT prevalence was <1/1,000 population. Interpretation The surveillance surveys, as proposed by WHO, showed no evidence for re-emergence of trachoma in two districts of Nepal. The low level and no significant increase by age in seroprevalence of antibodies to C trachomatis pgp3 antigen deserve further investigation as a marker of interruption of transmission. PMID:27654497
Directory of Open Access Journals (Sweden)
Pierre-Louis Malosse
2009-10-01
Full Text Available Rarement la conversion – concept, événement, acte – a tenu une place telle qu’au IVe siècle après Jésus-Christ, dans les années qui mènent de la conversion d’un empereur (Constantin à celle de l’empire. Dans le monde oriental, dominé par la culture hellénique, la conversion religieuse rencontre un modèle depuis longtemps reconnu, celui de la conversion philosophique (ou à la philosophie. Entre l'une et l'autre, il existe une certaine porosité, plus ou moins consciente, comme l'attestent en des directions opposées le cas des milieux philosophiques alexandrins – y compris peut-être Arios –, ou celui de Julien. D'autre part, à l'orée du IVe siècle, la conversion chrétienne a déjà une longue histoire. La nouveauté de l'Antiquité tardive, outre le changement d'échelle, du petit nombre à la masse et du marginal à l'officiel avec le soutien de l'État, est de poser la question du rapport de la conversion religieuse à la culture traditionnelle, question qui ne se posait pas à propos de la conversion philosophique, puisque celle-ci était une composante de cette culture, question qui se pose particulièrement au moment où les convertis prétendent prendre en charge la culture. Plus précisément, il s'agit d'une confrontation avec la paideia, concept qui embrasse et unit étroitement culture et éducation. Chez les auteurs qui s’y réfèrent, que ce soit explicitement ou implicitement, la conversion se définit par rapport à la paideia tour à tour en termes d’exclusion, de concurrence et de complémentarité.Conversion –as a concept, as an event and as a deed – was seldom as imporant as it was during Forth Century AD, from the conversion of an emperor (Constantine to the conversion of the whole Empire. In the Greek speaking and thinking East, religious conversion came across philosophical conversion model, which had been known and admitted for a long time. So, philosophical conversion could
Institute of Scientific and Technical Information of China (English)
DING ZHITAO
2010-01-01
@@ Historic monuments in Dengfeng, formally referred to as the Center of Heaven and Earth, in Henan Province, as well as Danxia Landform in several southern and eastern Chines provinces, were proclaimed UNESCO world heritage sites recently.
Powers, Shelley
2007-01-01
Ajax can bring many advantages to an existing web application without forcing you to redo the whole thing. This book explains how you can add Ajax to enhance, rather than replace, the way your application works. For instance, if you have a traditional web application based on submitting a form to update a table, you can enhance it by adding the capability to update the table with changes to the form fields, without actually having to submit the form. That's just one example.Adding Ajax is for those of you more interested in extending existing applications than in creating Rich Internet Applica
Around the World, Holidays Bring Added Pounds
... holidays is often reflected by the increase in attendance at gyms and health clubs right after the ... assistant professor, athletic training and sports medicine, Quinnipiac University, Hamden, Conn.; Stephanie Schiff, R.D.N., registered ...
Adding local flavor to world class imaging.
Kalbhen, Carl L
2007-01-01
Chicago, the host city for the annual meeting of the RSNA (Radiological Society of North America), is the quintessential place to obtain certain foods, among them deep dish pizza, the Italian beef sandwich, and the Chicago-style hot dog. Given some appropriate nutritional concerns about these items, it is important to realize that healthier alternatives are grown, produced, and sold regionally. Chicago has also for years been known as one of America's great restaurant towns. However, the French delicacy foie gras cannot be found on the menu of any of its five-star establishments, as the sale of this dish became illegal in 2006. Diagnostic imaging offers a unique perspective on the local Chicago cuisine.
Institute of Scientific and Technical Information of China (English)
无
2010-01-01
Historic monuments in Dengfeng,formally referred to as the Center of Heaven and Earth,in Henan Province,as well as Danxia Landform in several southern and eastern Chinese provinces,were proclaimed UNESCO world heritage sites recently. The group of constructions in Dengfeng includes some of the best examples of ancient Chinese buildings devoted to rituals,science,technology and education. Most of the constructions present vividly a history of central China’s architecture from the last 2,000 years and contain very valuable material for studies.
Natsuume, Makoto
2014-01-01
This is the draft version of a textbook on "real-world" applications of the AdS/CFT duality for beginning graduate students in particle physics and for researchers in the other fields. The aim of this book is to provide background materials such as string theory, general relativity, nuclear physics, nonequilibrium physics, and condensed-matter physics as well as some key applications of the AdS/CFT duality in a single textbook. Contents: (1) Introduction, (2) General relativity and black holes, (3) Black holes and thermodynamics, (4) Strong interaction and gauge theories, (5) The road to AdS/CFT, (6) The AdS spacetime, (7) AdS/CFT - equilibrium, (8) AdS/CFT - adding probes, (9) Basics of nonequilibrium physics, (10) AdS/CFT - nonequilibrium, (11) Other AdS spacetimes, (12) Applications to quark-gluon plasma, (13) Basics of phase transition, (14) AdS/CFT - phase transition.
Institute of Scientific and Technical Information of China (English)
无
2010-01-01
China Danxia gets added to world heritage list as a natural site On August 1,2010,UNESCO’s World Heritage Committee inscribed China Danxia as a natural site in the world heritage list at its 34th session held from July 25 to August 3 this year in Brasilia,capital of Brazil.
de Boer, J.
2000-01-01
In these notes we discuss various aspects of string theory in AdS spaces. We briefly review the formulation in terms of Green-Schwarz, NSR, and Berkovits variables, as well as the construction of exact conformal field theories with AdS backgrounds. Based on lectures given at the Kyoto YITP Workshop
Online Ad Assignment with an Ad Exchange
Dvořák, Wolfgang; Henzinger, Monika
2016-01-01
Ad exchanges are becoming an increasingly popular way to sell advertisement slots on the internet. An ad exchange is basically a spot market for ad impressions. A publisher who has already signed contracts reserving advertisement impressions on his pages can choose between assigning a new ad impression for a new page view to a contracted advertiser or to sell it at an ad exchange. This leads to an online revenue maximization problem for the publisher. Given a new impression to sell decide whe...
Costa, Miguel S.; Greenspan, Lauren; Oliveira, Miguel; Penedones, João; Santos, Jorge E.
2016-06-01
We consider solutions in Einstein-Maxwell theory with a negative cosmological constant that asymptote to global AdS 4 with conformal boundary {S}2× {{{R}}}t. At the sphere at infinity we turn on a space-dependent electrostatic potential, which does not destroy the asymptotic AdS behaviour. For simplicity we focus on the case of a dipolar electrostatic potential. We find two new geometries: (i) an AdS soliton that includes the full backreaction of the electric field on the AdS geometry; (ii) a polarised neutral black hole that is deformed by the electric field, accumulating opposite charges in each hemisphere. For both geometries we study boundary data such as the charge density and the stress tensor. For the black hole we also study the horizon charge density and area, and further verify a Smarr formula. Then we consider this system at finite temperature and compute the Gibbs free energy for both AdS soliton and black hole phases. The corresponding phase diagram generalizes the Hawking-Page phase transition. The AdS soliton dominates the low temperature phase and the black hole the high temperature phase, with a critical temperature that decreases as the external electric field increases. Finally, we consider the simple case of a free charged scalar field on {S}2× {{{R}}}t with conformal coupling. For a field in the SU(N ) adjoint representation we compare the phase diagram with the above gravitational system.
Callebaut, Nele; Samberg, Andreas; Toldo, Chiara
2015-01-01
We study segmented strings in flat space and in $AdS_3$. In flat space, these well known classical motions describe strings which at any instant of time are piecewise linear. In $AdS_3$, the worldsheet is composed of faces each of which is a region bounded by null geodesics in an $AdS_2$ subspace of $AdS_3$. The time evolution can be described by specifying the null geodesic motion of kinks in the string at which two segments are joined. The outcome of collisions of kinks on the worldsheet can be worked out essentially using considerations of causality. We study several examples of closed segmented strings in $AdS_3$ and find an unexpected quasi-periodic behavior. We also work out a WKB analysis of quantum states of yo-yo strings in $AdS_3$ and find a logarithmic term reminiscent of the logarithmic twist of string states on the leading Regge trajectory.
Brisco, Nicole
2011-01-01
Build, create, make, blog, develop, organize, structure, perform. These are just a few verbs that illustrate the visual world. These words create images that allow students to respond to their environment. Visual culture studies recognize the predominance of visual forms of media, communication, and information in the postmodern world. This…
Costa, Miguel S; Oliveira, Miguel; Penedones, João; Santos, Jorge E
2015-01-01
We consider solutions in Einstein-Maxwell theory with a negative cosmological constant that asymptote to global $AdS_{4}$ with conformal boundary $S^{2}\\times\\mathbb{R}_{t}$. At the sphere at infinity we turn on a space-dependent electrostatic potential, which does not destroy the asymptotic $AdS$ behaviour. For simplicity we focus on the case of a dipolar electrostatic potential. We find two new geometries: (i) an $AdS$ soliton that includes the full backreaction of the electric field on the $AdS$ geometry; (ii) a polarised neutral black hole that is deformed by the electric field, accumulating opposite charges in each hemisphere. For both geometries we study boundary data such as the charge density and the stress tensor. For the black hole we also study the horizon charge density and area, and further verify a Smarr formula. Then we consider this system at finite temperature and compute the Gibbs free energy for both $AdS$ soliton and black hole phases. The corresponding phase diagram generalizes the Hawkin...
Constructing Lifshitz solutions from AdS
Cassani, Davide
2011-01-01
Under general assumptions, we show that a gravitational theory in d+1 dimensions admitting an AdS solution can be reduced to a d-dimensional theory containing a Lifshitz solution with dynamical exponent z=2. Working in a d=4, N=2 supergravity setup, we prove that if the AdS background is N=2 supersymmetric, then the Lifshitz geometry preserves 1/4 of the supercharges, and we construct the corresponding Killing spinors. We illustrate these results in examples from supersymmetric consistent truncations of type IIB supergravity, enhancing the class of known 4-dimensional Lifshitz solutions of string theory. As a byproduct, we find a new AdS4 x S1 x T(1,1) solution of type IIB.
World Literature - World Culture
DEFF Research Database (Denmark)
Offering their own twenty-first-century perspectives - across generations, nationalities and disciplines -, the contributors to this anthology explore the idea of world literature for what it may add of new connections and itineraries to the study of literature and culture today. Covering a vast ...... historical material these essays, by a diverse group of scholars, examine the pioneers of world literature and the roles played by translation, migration and literary institutions in the circulation and reception of both national and cosmopolitan literatures....
Institute of Scientific and Technical Information of China (English)
王海涛
2005-01-01
首先介绍了Ad Hoc网络的基本概念、技术特点以及关键技术等,然后较为全面地归纳了Ad Hoc网络的典型应用,最后讨论了Ad Hoc网络的发展趋势和有待解决的问题.
AdS orbifolds and Penrose limits
Energy Technology Data Exchange (ETDEWEB)
Alishahiha, Mohsen; Sheikh-Jabbari, Mohammad M.; Tatar, Radu
2002-12-09
In this paper we study the Penrose limit of AdS{sub 5} orbifolds. The orbifold can be either in the pure spatial directions or space and time directions. For the AdS{sub 5}/{Lambda} x S{sup 5} spatial orbifold we observe that after the Penrose limit we obtain the same result as the Penrose limit of AdS{sub 5} x S{sup 5}/{Lambda}. We identify the corresponding BMN operators in terms of operators of the gauge theory on R x S{sup 3}/{Lambda}. The semi-classical description of rotating strings in these backgrounds have also been studied. For the spatial AdS orbifold we show that in the quadratic order the obtained action for the fluctuations is the same as that in S{sup 5} orbifold, however, the higher loop correction can distinguish between two cases.
Superradiant instability in AdS
Ganchev, Bogdan
2016-01-01
The phenomenon of superradiance in the context of asymptotically global AdS spacetimes is investigated with particular accent on its effect on the stability of the systems under consideration. To this end, the concept of an asymptotically AdS spacetime is explained, together with its implications on the boundary conditions at $\\mathcal{I}$, as well as the Newman-Penrose-Teukolsky formalism, whereby the Teukolsky master equation in a most general form for Kerr-AdS is given. Furthermore, work done in the cases of RN-AdS and Kerr-AdS is laid out in a concise manner, putting emphasis on the important steps taken in determining the endpoint of the superradiant instability in the two configurations. For the former this turns out to be a black hole with reduced charge and a static charged scalar condensate around it, whereas for the latter two of the more probable outcomes are presented, both of which imply a violation of one of the cosmic censorships.
Buchel, Alex; Lehner, Luis
2013-01-01
We construct boson stars in global Anti de Sitter (AdS) space and study their stability. Linear perturbation results suggest that the ground state along with the first three excited state boson stars are stable. We evolve some of these solutions and study their nonlinear stability in light of recent work \\cite{Bizon:2011gg} arguing that a weakly turbulent instability drives scalar perturbations of AdS to black hole formation. However evolutions suggest that boson stars are nonlinearly stable and immune to the instability for sufficiently small perturbation. Furthermore, these studies find other families of initial data which similarly avoid the instability for sufficiently weak parameters. Heuristically, we argue that initial data families with widely distributed mass-energy distort the spacetime sufficiently to oppose the coherent amplification favored by the instability. From the dual CFT perspective our findings suggest that there exist families of rather generic initial conditions in strongly coupled CFT ...
AdS solutions through transgression
Energy Technology Data Exchange (ETDEWEB)
Donos, A. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany). Theory Group; Gauntlett, J.P. [Imperial College, London (United Kingdom). Blackett Lab.]|[Imperial College, London (United Kingdom). The Institute for Mathematical Sciences; Kim, Nakwoo [Kyung Hee Univ., Seoul (Korea). Dept. of Physics and Research Inst. of Basic Science
2008-07-15
We present new classes of explicit supersymmetric AdS{sub 3} solutions of type IIB supergravity with non-vanishing five-form flux and AdS{sub 2} solutions of D=11 supergravity with electric four-form flux. The former are dual to two-dimensional SCFTs with (0,2) supersymmetry and the latter to supersymmetric quantum mechanics with two supercharges. We also investigate more general classes of AdS{sub 3} solutions of type IIB supergravity and AdS{sub 2} solutions of D=11 supergravity which in addition have non-vanishing three-form flux and magnetic four-form flux, respectively. The construction of these more general solutions makes essential use of the Chern-Simons or ''transgression'' terms in the Bianchi identity or the equation of motion of the field strengths in the supergravity theories. We construct infinite new classes of explicit examples and for some of the type IIB solutions determine the central charge of the dual SCFTs. The type IIB solutions with non-vanishing three-form flux that we construct include a two-torus, and after two T-dualities and an S-duality, we obtain new AdS3 solutions with only the NS fields being non-trivial. (orig.)
Open string fluctuations in AdS space with and without torsion
DEFF Research Database (Denmark)
Larsen, A.L.; Lomholt, Michael Andersen
2003-01-01
dangerous than expected in these cases. The general formalism can be straightforwardly used also to study the (bosonic part of the) fluctuations around the closed strings, recently considered in connection with the AdS/conformal field theory duality, on AdS ×S and AdS ×S ×T . © 2003 The American Physical......The equations of motion and boundary conditions for the fluctuations around a classical open string, in a curved space-time with torsion, are considered in compact and world-sheet covariant form. The rigidly rotating open strings in anti-de Sitter space with and without torsion are investigated...
Refined Holographic Entanglement Entropy for the AdS Solitons and AdS black Holes
Ishihara, Masafumi; Ning, Bo
2012-01-01
We consider the refinement of the holographic entanglement entropy on a disk region for the holographic dual theories to the AdS solitons and AdS black holes, including the corrected ones by the Gauss-Bonnet term. The AdS soliton is dual to a gapped system with an IR fixed-point. The refinement is obtained by extracting the UV-independent piece of the holographic entanglement entropy. We then study the renormalization group (RG) flow of the refinement by tuning the linear size of the chosen disk region. Our main results are (i) the RG flow of the refinement decreases monotonically for most of the cases; (ii) there is no topological entanglement entropy for AdS$_5$ soliton even with Gauss-Bonnet correction; (iii) for the AdS black holes, the refinement obeys the volume law at IR regime, and the transition between UV and IR regimes is a smooth crossover; however, the crossover will turn into phase transition by the Gauss-Bonnet correction; (iv) for the AdS solitons, there are discontinuous phase transitions bet...
DEFF Research Database (Denmark)
Liu, Yawu; Mattila, Jussi; Ruiz, Miguel �ngel Mu�oz
2013-01-01
To compare the accuracies of predicting AD conversion by using a decision support system (PredictAD tool) and current research criteria of prodromal AD as identified by combinations of episodic memory impairment of hippocampal type and visual assessment of medial temporal lobe atrophy (MTA) on MRI...
S-matrix for strings on η-deformed AdS5 x S5
Arutyunov, G.E.; Borsato, R.; Frolov, S.
2013-01-01
We determine the bosonic part of the superstring sigma model Lagrangian on η-deformed AdS5 x S5, and use it to compute the perturbative world-sheet scattering matrix of bosonic particles of the model. We then compare it with the large string tension limit of the q-deformed S-matrix and find exact ag
S-matrix for strings on η-deformed AdS5 x S5
Arutyunov, Gleb; Borsato, Riccardo; Frolov, Sergey
2013-01-01
We determine the bosonic part of the superstring sigma model Lagrangian on η-deformed AdS5 × S5, and use it to compute the perturbative world-sheet scattering matrix of bosonic particles of the model. We then compare it with the large string tension limit of the q-deformed S-matrix and find exact ag
S-matrix for strings on $\\eta$-deformed AdS5 x S5
Arutyunov, Gleb; Frolov, Sergey
2014-01-01
We determine the bosonic part of the superstring sigma model Lagrangian on $\\eta$-deformed AdS5 x S5, and use it to compute the perturbative world-sheet scattering matrix of bosonic particles of the model. We then compare it with the large string tension limit of the q-deformed S-matrix and find exact agreement.
Hertog, Thomas
2004-12-01
We review some properties of N=8 gauged supergravity in four dimensions with modified, but AdS invariant boundary conditions on the m2 = -2 scalars. There is a one-parameter class of asymptotic conditions on these fields and the metric components, for which the full AdS symmetry group is preserved. The generators of the asymptotic symmetries are finite, but acquire a contribution from the scalar fields. For a large class of such boundary conditions, we find there exist black holes with scalar hair that are specified by a single conserved charge. Since Schwarschild-AdS is a solution too for all boundary conditions, this provides an example of black hole non-uniqueness. We also show there exist solutions where smooth initial data evolve to a big crunch singularity. This opens up the possibility of using the dual conformal field theory to obtain a fully quantum description of the cosmological singularity, and we report on a preliminary study of this.
Adding more value to added-value
DEFF Research Database (Denmark)
Marian, Livia
regulation. The results of a qualitative concept test reveal positive attitudes towards the proposed production process. The discussions about fewer standards being sufficient or about options “in-between” conventional and organic standards indicate that the difference in production processes is noticed, yet...... it is probably valued less than expected. The added attributes need to be thoroughly considered when developing and marketing “organic plus” products, as their effect on other product characteristics (e.g. high prices) can detract from their added value....
Probing crunching AdS cosmologies
Kumar, S. Prem; Vaganov, Vladislav
2016-02-01
Holographic gravity duals of deformations of CFTs formulated on de Sitter spacetime contain FRW geometries behind a horizon, with cosmological big crunch singularities. Using a specific analytically tractable solution within a particular single scalar truncation of {N}=8 supergravity on AdS4, we first probe such crunching cosmologies with spacelike radial geodesics that compute spatially antipodal correlators of large dimension boundary operators. At late times, the geodesics lie on the FRW slice of maximal expansion behind the horizon. The late time two-point functions factorise, and when transformed to the Einstein static universe, they exhibit a temporal non-analyticity determined by the maximal value of the scale factor ã max. Radial geodesics connecting antipodal points necessarily have de Sitter energy Ɛ ≲ ã max, while geodesics with Ɛ > ã max terminate at the crunch, the two categories of geodesics being separated by the maximal expansion slice. The spacelike crunch singularity is curved "outward" in the Penrose diagram for the deformed AdS backgrounds, and thus geodesic limits of the antipodal correlators do not directly probe the crunch. Beyond the geodesic limit, we point out that the scalar wave equation, analytically continued into the FRW patch, has a potential which is singular at the crunch along with complex WKB turning points in the vicinity of the FRW crunch. We then argue that the frequency space Green's function has a branch point determined by ã max which corresponds to the lowest quasinormal frequency.
Directory of Open Access Journals (Sweden)
Palma Peña-Jiménez, Ph.D.
2011-01-01
Full Text Available During election campaigns the political spot has a clear objective: to win votes. This message is communicated to the electorate through television and Internet, and usually presents a negative approach, which includes a direct critical message against the opponent, rather than an exposition of proposals. This article is focused on the analysis of the campaign attack video ad purposely created to encourage the disapproval of the political opponent among voters. These ads focus on discrediting the opponent, many times, through the transmission of ad hominem messages, instead of disseminating the potential of the political party and the virtues and manifesto of its candidate. The article reviews the development of the attack ad since its first appearance, which in Spain dates back to 1996, when the famous Doberman ad was broadcast, and examines the most memorable campaign attack ads.
AdS5×S(5) mirror model as a string sigma model.
Arutyunov, Gleb; van Tongeren, Stijn J
2014-12-31
Doing a double Wick rotation in the world sheet theory of the light cone AdS5×S(5) superstring results in an inequivalent, so-called mirror theory that plays a central role in the field of integrability in the AdS-CFT correspondence. We show that this mirror theory can be interpreted as the light cone theory of a free string on a different background. This background is related to dS5×H(5) by a double T-duality, and has hidden supersymmetry. The geometry can also be extracted from an integrable deformation of the AdS5×S(5) sigma model, and we prove the observed mirror duality of these deformed models at the bosonic level as a byproduct. While we focus on AdS5×S(5), our results apply more generally.
Probing crunching AdS cosmologies
Kumar, S Prem
2015-01-01
Holographic gravity duals of deformations of CFTs formulated on de Sitter spacetime contain FRW geometries behind a horizon, with cosmological big crunch singularities. Using a specific analytically tractable solution within a particular single scalar truncation of N=8 supergravity on AdS_4, we first probe such crunching cosmologies with spacelike radial geodesics that compute spatially antipodal correlators of large dimension boundary operators. At late times, the geodesics lie on the FRW slice of maximal expansion behind the horizon. The late time two-point functions factorise, and when transformed to the Einstein static universe, they exhibit a temporal non-analyticity determined by the maximal value of the scale factor a_{max} . Radial geodesics connecting antipodal points necessarily have de Sitter energy E \\leq a_{max}, while geodesics with E > a_{max} terminate at the crunch, the two categories of geodesics being separated by the maximal expansion slice. The spacelike crunch singularity is curved "outw...
Adamo, Tim; Williams, Jack
2016-01-01
We consider the application of twistor theory to five-dimensional anti-de Sitter space. The twistor space of AdS$_5$ is the same as the ambitwistor space of the four-dimensional conformal boundary; the geometry of this correspondence is reviewed for both the bulk and boundary. A Penrose transform allows us to describe free bulk fields, with or without mass, in terms of data on twistor space. Explicit representatives for the bulk-to-boundary propagators of scalars and spinors are constructed, along with twistor action functionals for the free theories. Evaluating these twistor actions on bulk-to-boundary propagators is shown to produce the correct two-point functions.
Holography of AdS vacuum bubbles
Energy Technology Data Exchange (ETDEWEB)
Barbon, J.L.F. [Instituto de Fisica Teorica IFT UAM/CSIC, Cantoblanco, Madrid 28049 (Spain); Rabinovici, E. [Racah Institute of Physics, Hebrew University, Jerusalem 91904 (Israel)
2011-07-15
We consider the fate of AdS vacua connected by tunneling events. A precise holographic dual of thin-walled Coleman-de Luccia bounces is proposed in terms of Fubini instantons in an unstable CFT. This proposal is backed by several qualitative and quantitative checks, including the precise calculation of the instanton action appearing in evaluating the decay rate. Big crunches manifest themselves as time dependent processes which reach the boundary of field space in a finite time. The infinite energy difference involved is identified on the boundary and highlights the ill-defined nature of the bulk setup. We propose a qualitative scenario in which the crunch is resolved by stabilizing the CFT, so that all attempts at crunching always end up shielded from the boundary by the formation of black hole horizons. In all these well defined bulk processes the configurations have the same asymptotics and are finite energy excitations.
DEFF Research Database (Denmark)
Kaspersen, Peter
2007-01-01
På grundlag af evalueringer og forskning i gymnasiereformen 2005 foreslås det at skille problemerne ad i forskellige niveauer. Herved kan der arbejdes med niveaudelte løsninger.......På grundlag af evalueringer og forskning i gymnasiereformen 2005 foreslås det at skille problemerne ad i forskellige niveauer. Herved kan der arbejdes med niveaudelte løsninger....
John Wiley & Sons
2004-01-01
"Assimilating the most up-to-date information on research and development activities in this rapidly growing area, Mobile Ad Hoc Networking covers physical, data link, network, and transport layers, as well as application, security, simulation, and power management issues in sensor, local area, personal, and mobile ad hoc networks. Each of the book's sixteen chapters has been written by a top expert and discusses in-depth the most important topics in the field. Mobile Ad Hoc Networking is an excellent reference and guide for professionals seeking an in-depth examination of topics that also provides a comprehensive overview of the current state-of-the-art."--Jacket.
DEFF Research Database (Denmark)
Jensen, Per Anker; Katchamart, Akarapong
2011-01-01
Purpose: To investigate how Facilities Management (FM) can add value and develop a management concept that can assist facilities managers in implementing value adding strategies and practices. Theory: The study is based on the management model for FM included in the European FM standards, recent...... theories on added value of FM and real estate and the related concept of Value Management from building projects. The study is related to the EuroFM research group on The Added Value of FM. Design/methodology/approach: The study outlines a preliminary theoretical based management concept, which...... is investigated, tested and discussed based on a case study of an international corporation. Findings: The study shows that the management model for FM creates a relevant starting point but also that stakeholder and relationship management is an essential aspect of Value Adding Management. The case study confirms...
Laurent Guiraud
1998-01-01
When the Low-Energy Antiproton Ring (LEAR) was stopped in 1996, because of its costly operation, a cheaper way of continuing low-energy antiproton physics was sought. The Antiproton-Collector (AC), added in 1987 to the Antiproton Accumulator (AA) to provide a tenfold intensity increase, was converted into the Antiproton-Decelerator (AD). Antiprotons from the target at 3.5 GeV/c are decelerated to 100 MeV/c, and fast-ejected to the experiments. Major changes were necessary. Above all, the conversion from a constant-field machine to one with a magnetic cycle, modulating the field by an impressive factor 35. New systems for stochastic and electron cooling had to be added. Beam diagnostics at an intensity of only 2E7 antiprotons was a challenge. In 2000, the AD began delivery of antiprotons to the experiments.
Bena, Iosif; Puhm, Andrea
2015-01-01
It was argued in arXiv:1203.4227 that the five-dimensional near-horizon extremal Kerr (NHEK) geometry can be embedded in String Theory as the infrared region of an infinite family of non-supersymmetric geometries that have D1, D5, momentum and KK monopole charges. We show that there exists a method to embed these geometries into asymptotically-AdS_3 x S^3/Z_N solutions, and hence to obtain infinite families of flows whose infrared is NHEK. This indicates that the CFT dual to the NHEK geometry is the IR fixed point of a Renormalization Group flow from a known local UV CFT and opens the door to its explicit construction.
Kaloper, Nemanja
2004-01-01
We paste together patches of $AdS_6$ to find solutions which describe two 4-branes intersecting on a 3-brane with non-zero tension. We construct explicitly brane arrays with Minkowski, de Sitter and Anti-de Sitter geometries intrinsic to the 3-brane, and describe how to generalize these solutions to the case of $AdS_{4+n}$, $n>2$, where $n$ $n+2$-branes intersect on a 3-brane. The Minkowski and de Sitter solutions localize gravity to the intersection, leading to 4D Newtonian gravity at large ...
Heat kernels on cone of AdS2 and k-wound circular Wilson loop in AdS5 × S5 superstring
Bergamin, R.; Tseytlin, A. A.
2016-04-01
We compute the one-loop world-sheet correction to partition function of {{AdS}}5× {{{S}}}5 superstring that should be representing k-fundamental circular Wilson loop in planar limit. The 2d metric of the minimal surface ending on k-wound circle at the boundary is that of a cone of AdS2 with deficit 2π (1-k). We compute the determinants of 2d fluctuation operators by first constructing heat kernels of scalar and spinor Laplacians on the cone using the Sommerfeld formula. The final expression for the k-dependent part of the one-loop correction has simple integral representation but is different from earlier results.
Kaloper, Nemanja
2004-01-01
We paste together patches of $AdS_6$ to find solutions which describe two 4-branes intersecting on a 3-brane with non-zero tension. We construct explicitly brane arrays with Minkowski, de Sitter and Anti-de Sitter geometries intrinsic to the 3-brane, and describe how to generalize these solutions to the case of $AdS_{4+n}$, $n>2$, where $n$ $n+2$-branes intersect on a 3-brane. The Minkowski and de Sitter solutions localize gravity to the intersection, leading to 4D Newtonian gravity at large distances. We show this explicitly in the case of Minkowski origami by finding the zero-mode graviton, and computing the couplings of the bulk gravitons to the matter on the intersection. In de Sitter case, this follows from the finiteness of the bulk volume. The effective 4D Planck scale depends on the square of the fundamental 6D Planck scale, the $AdS_6$ radius and the angles between the 4-branes and the radial $AdS$ direction, and for the Minkowski origami it is $M_4{}^2 = {2/3} \\Bigl(\\tan \\alpha_1 + \\tan \\alpha_2 \\Bi...
DEFF Research Database (Denmark)
Hillersdal, Line
in the context of the 'ad libitum meal'. The analytical interest is thus what kind of eaters and bodies are enacted in the meal test and what ideas of prevention and treatment are embedded in their standards. Drawing from ongoing empirical work among Danish obesity researchers performing scientific meal tests I...... ask what make up food stuff and eaters in the meal tests? More specifically I explore a scientific testing of changes in taste preferences before and after weight-loss surgery using an ad libitum buffet with a selection of different foods and another testing the effect of exercise on appetite also...... using an ad libitum meal consisting of spaghetti bolognaise. I analyse the entanglement and concurrence of different knowledge practices and show how several scalings of appetite play out, one ex explaining the aim of the test, being to ”measure what your body would want the most” and hence producing...
Rashvand, Habib
2013-01-01
Motivated by the exciting new application paradigm of using amalgamated technologies of the Internet and wireless, the next generation communication networks (also called 'ubiquitous', 'complex' and 'unstructured' networking) are changing the way we develop and apply our future systems and services at home and on local, national and global scales. Whatever the interconnection - a WiMAX enabled networked mobile vehicle, MEMS or nanotechnology enabled distributed sensor systems, Vehicular Ad hoc Networking (VANET) or Mobile Ad hoc Networking (MANET) - all can be classified under new networking s
Two worlds collide: Interacting shells in AdS spacetime and chaos
Brito, Richard; Rocha, Jorge V
2016-01-01
We study the simplest two-body problem in asymptotically anti-de Sitter spacetime: two, infinitely-thin, concentric spherical shells of matter. We include only gravitational interaction between the two shells, but we show that the dynamics of this system is highly nontrivial. We observe prompt collapse to a black hole, delayed collapse and even perpetual oscillatory motion, depending on the initial location of the shells (or their energy content). The system exhibits critical behavior, and we show strong hints that it is also chaotic.
Localization on $AdS_2\\times S^1$
David, Justin R; Gupta, Rajesh Kumar; Narain, Kumar
2016-01-01
Conformal symmetry relates the metric on $AdS_2 \\times S^{1}$ to that of $S^3$. This implies that under a suitable choice of boundary conditions for fields on $AdS_2$ the partition function of conformal field theories on these spaces must agree which makes $AdS_2 \\times S^{1}$ a good testing ground to study localization on non-compact spaces. We study supersymmetry on $AdS_2\\times S^1$ and determine the localizing Lagrangian for ${\\cal N}=2$ supersymmetric Chern-Simons theory on $AdS_2\\times S^1$. We evaluate the partition function of ${\\cal N}=2$ supersymmetric Chern-Simons theory on $AdS_2 \\times S^1$ using localization, where the radius of $S^1$ is $q$ times that of $AdS_2$. With boundary conditions on $AdS_2\\times S^1$ which ensure that all the physical fields are normalizable and lie in the space of square integrable wave functions in $AdS_2$, the result for the partition function precisely agrees with that of the theory on the $q$-fold covering of $S^3$.
Israel, D
2005-01-01
We study the exact construction of D-branes in Lorentzian AdS(3). We start by defining a family of conformal field theories that gives a natural Euclidean version of the SL(2,R) CFT and does not correspond to H(3)+, the analytic continuation of AdS(3). We argue that one can recuperate the exact CFT results of Lorentzian AdS(3), upon an analytic continuation in the moduli space of these conformal field theories. Then we construct exact boundary states for various symmetric and symmetry-breaking D-branes in AdS(3).
Heller, René
2014-01-01
To be habitable, a world (planet or moon) does not need to be located in the stellar habitable zone (HZ), and worlds in the HZ are not necessarily habitable. Here, we illustrate how tidal heating can render terrestrial or icy worlds habitable beyond the stellar HZ. Scientists have developed a language that neglects the possible existence of worlds that offer more benign environments to life than Earth does. We call these objects "superhabitable" and discuss in which contexts this term could be used, that is to say, which worlds tend to be more habitable than Earth. In an appendix, we show why the principle of mediocracy cannot be used to logically explain why Earth should be a particularly habitable planet or why other inhabited worlds should be Earth-like. Superhabitable worlds must be considered for future follow-up observations of signs of extraterrestrial life. Considering a range of physical effects, we conclude that they will tend to be slightly older and more massive than Earth and that their host star...
Configurational entropy in brane-world models
Energy Technology Data Exchange (ETDEWEB)
Correa, R. A. C., E-mail: fis04132@gmail.com [CCNH, Universidade Federal do ABC, 09210-580, Santo André, SP (Brazil); Rocha, Roldão da, E-mail: roldao.rocha@ufabc.edu.br [CMCC, Universidade Federal do ABC, 09210-580, Santo André, SP (Brazil); International School for Advanced Studies (SISSA), Via Bonomea 265, 34136, Trieste (Italy)
2015-11-02
In this work we investigate the entropic information on thick brane-world scenarios and its consequences. The brane-world entropic information is studied for the sine-Gordon model and hence the brane-world entropic information measure is shown to be an accurate way for providing the most suitable range for the bulk AdS curvature, in particular from the informational content of physical solutions. Besides, the brane-world configurational entropy is employed to demonstrate a high organisational degree in the structure of the configuration of the system, for large values of a parameter of the sine-Gordon model but the one related to the AdS curvature. The Gleiser and Stamatopoulos procedure is finally applied in order to achieve a precise correlation between the energy of the system and the brane-world configurational entropy.
Configurational entropy in brane-world models
Energy Technology Data Exchange (ETDEWEB)
Correa, R.A.C. [CCNH, Universidade Federal do ABC, Santo Andre, SP (Brazil); Rocha, Roldao da [CMCC, Universidade Federal do ABC, Santo Andre, SP (Brazil); International School for Advanced Studies (SISSA), Trieste (Italy)
2015-11-15
In this work we investigate the entropic information on thick brane-world scenarios and its consequences. The brane-world entropic information is studied for the sine-Gordon model and hence the brane-world entropic information measure is shown to be an accurate way for providing the most suitable range for the bulk AdS curvature, in particular from the informational content of physical solutions. Besides, the brane-world configurational entropy is employed to demonstrate a high organisational degree in the structure of the configuration of the system, for large values of a parameter of the sine-Gordon model but the one related to the AdS curvature. The Gleiser and Stamatopoulos procedure is finally applied in order to achieve a precise correlation between the energy of the system and the brane-world configurational entropy. (orig.)
Configurational entropy in brane-world models
Correa, R. A. C.; da Rocha, Roldão
2015-11-01
In this work we investigate the entropic information on thick brane-world scenarios and its consequences. The brane-world entropic information is studied for the sine-Gordon model and hence the brane-world entropic information measure is shown to be an accurate way for providing the most suitable range for the bulk AdS curvature, in particular from the informational content of physical solutions. Besides, the brane-world configurational entropy is employed to demonstrate a high organisational degree in the structure of the configuration of the system, for large values of a parameter of the sine-Gordon model but the one related to the AdS curvature. The Gleiser and Stamatopoulos procedure is finally applied in order to achieve a precise correlation between the energy of the system and the brane-world configurational entropy.
Directory of Open Access Journals (Sweden)
Wulan Roro Retno
2017-01-01
Full Text Available Cosmetics industry created the beauty myth for women through advertising. A cosmetic ad in Indonesia has spread a new concept of white skin: East Asia beauty myth. The white concept of Asia white skin basically derived from colonial legacy. The purpose of the research was analyzing the beauty myth in Indonesia ads using postcolonial perspective. The principal result brought the discourse analysis and postcolonial perspective a new insight in communication research. Particularly on media and cultural studies. Major conclusions showed that the beauty myth since the Dutch colonial period never been change. The main concept is always in colonialism’s idea: “white is better”. The West is better than the East.
Shelah, Saharon
2011-01-01
We address the following question: Can we expand an NIP theory by adding a linear order such that the expansion is still NIP? Easily, if acl(A)=A for all A, then this is true. Otherwise, we give counterexamples. More precisely, there is a totally categorical theory for which every expansion by a linear order has IP. There is also an \\omega-stable NDOP theory for which every expansion by a linear order interprets bounded arithmetic.
National Aeronautics and Space Administration — World Wind allows any user to zoom from satellite altitude into any place on Earth, leveraging high resolution LandSat imagery and SRTM elevation data to experience...
AdS 3-manifolds and Higgs bundles
DEFF Research Database (Denmark)
Alessandrini, Daniele; Li, Qiongling
2015-01-01
In this paper we investigate the relationships between closed AdS 3-manifolds and Higgs bundles. We have a new way to construct AdS structures that allows us to see many of their properties explicitly, for example we can recover the very recent formula by Tholozan for the volumes. We also find...
Goodman, Alyssa
images can be extracted from articles, we will attempt to "astroreference" those images in order allow for their overlay on the sky. "Astroreferencing" is the analog of "georeferencing," where coordinate information is used to overlay information on maps. Our first pass at astroreferencing will be made using the astrometry.net program, in collaboration with one of its creators. If enough optically-visible stars are present in an image, astrometry.net can place it where it goes on the sky. Only a small fraction of ADS holdings contain images solvable by astrometry.net, but for the articles which do, reviving the data in this way holds tremendous value-especially in the case of historically important observations. Lastly, we will also astroreference images by text-mining to extract "metadata" buried in the figure captions and text. As it is built, the ADSASS will effectively create dynamic data layers of astrotags and astroreferenced images. Users will be able to explore these layers using a wide variety of free all-sky data viewers. Our group and our collaborators have been involved in the development of the WorldWide Telescope and Aladin programs, so we will use those to develop examples of how we intend for the ADSASS to be used. But, we plan to ensure that the data feed represented by the ADSASS will be ingestible by any program capable of understanding sky coordinates and all-sky views. Our proposal can only give a glimpse into the wealth of science it will enable, which includes everything from observation-planning to data discovery to studying the sky distributions of classes of objects. Just as it would have been hard to predict the full and amazing impact of GIS and GPS on society, it is similarly hard to gauge the full impact of the NASA ADSASS. The ADS on its own is already the envy of other sciences as a unified research tool, with the advent of the ADSASS, NASA will have led the way to the future once again.
Pathologies in Lovelock AdS Black Branes and AdS/CFT
Takahashi, Tomohiro
2011-01-01
We study the pathologies in AdS black branes in Lovelock theory. More precisely, we examine the conditions that AdS black branes have the naked singularity, the ghost instability and the dynamical instability. From the point of view of the AdS/CFT correspondence, the pathologies in AdS black branes indicate the pathologies in the corresponding CFT. Hence, we need to be careful when we apply AdS/CFT in Lovelock theory to various phenomena such as the shear viscosity to entropy ratio in strongly coupled quantum filed theory.
Institute of Scientific and Technical Information of China (English)
李小艳
2010-01-01
There is the trend that now people appreciate those who are slim and regard slim even thin people beautiful. The thinner a person is, the more beautiful. Women, born to pursuit beauty, try various means to follow the trend. We all watch TV, and find a lot of advertisements on diet. The effect of them is tremendous. We all know the fact that it is not at all the better mouse trap will catch mouse. The sales methods are more important. If an advertisement is very interesting and seemingly effective, people will be lured by the ad and then try some of the products.
DEFF Research Database (Denmark)
2014-01-01
The article asks whether it is not the responsibility of corporations to address the issue of women being underrepresented in Danish management jobs. In other words, it is argued that corporations should be encouraged to engage more actively in the recruitment of both men and women for management...... that this agreement reflects a high degree of conservatism in the system where men enjoy a considerable advantage and where procedures that ensure male dominance are perpetuated even in the linguistic and discursive construction of job ads....
Rudolfs Bems; Robert C. Johnson
2012-01-01
This paper updates the conceptual foundations for measuring real effective exchange rates (REERs) to allow for vertical specialization in trade. We derive a value-added REER describing how demand for the value added that a country produces changes as the price of its value added changes relative to competitors. We then compute this index for 42 countries from 1970-2009 using trade measured in value added terms and GDP deflators. There are substantial differences between value-added and conven...
Energy Technology Data Exchange (ETDEWEB)
Kaloper, Nemanja E-mail: kaloper@solid.ucdavis.edu
2004-05-01
We paste together patches of AdS{sub 6} to find solutions which describe two 4-branes intersecting on a 3-brane with non-zero tension. We construct explicitly brane arrays with Minkowski, de Sitter and Anti-de Sitter geometries intrinsic to the 3-brane, and describe how to generalize these solutions to the case of AdS{sub 4+n,} n > 2, where n n+2-branes intersect on a 3-brane. The Minkowski and de Sitter solutions localize gravity to the intersection, leading to 4D Newtonian gravity at large distances. We show this explicitly in the case of Minkowski origami by finding the zero-mode graviton, and computing the couplings of the bulk gravitons to the matter on the intersection. In de Sitter case, this follows from the finiteness of the bulk volume. The effective 4D Planck scale depends on the square of the fundamental 6D Planck scale, the AdS{sub 6} radius and the angles between the 4-branes and the radial AdS direction, and for the Minkowski origami it is M{sub 4}{sup 2} = {l_brace}2/3{r_brace}(tan {alpha}{sub 1}+tan {alpha}{sub 2})M{sub *}{sup 4}L{sup 2}. If M{sub *} {approx} few x TeV this may account for the Planck-electroweak hierarchy even if L {approx} 10{sup -4}m, with a possibility for sub-millimeter corrections to the Newton's law. We comment on the early universe cosmology of such models. (author)
An $xp$ model on $AdS_2$ spacetime
Molina-Vilaplana, Javier
2013-01-01
In this paper we formulate the $xp$ model on the AdS$_2$ spacetime. We find that the spectrum of the Hamiltonian has positive and negative eigenvalues, equal in magnitude, given by a harmonic oscillator with a zero point energy parameterized by the AdS radius, measured in units of a fundamental length of the model. We also construct the generators of the isometry group SO(2,1) of the AdS$_2$ spacetime, and discuss the relation with conformal quantum mechanics.
Institute of Scientific and Technical Information of China (English)
张严心; 周丽
2014-01-01
In the current days, the search for information and the need for global communication have already promoted English from being the language of people in different countries as the international language. This essay will give some arguments about the inevitability of variety of world Englishes and its characteristics, and then explain that what Standard English is and examples about the standards in English.
Directory of Open Access Journals (Sweden)
Hong-Chuan Yang
2007-01-01
Full Text Available We study the energy-efficient configuration of multihop paths with automatic repeat request (ARQ mechanism in wireless ad hoc networks. We adopt a cross-layer design approach and take both the quality of each radio hop and the battery capacity of each transmitting node into consideration. Under certain constraints on the maximum tolerable transmission delay and the required packet delivery ratio, we solve optimization problems to jointly schedule the transmitting power of each transmitting node and the retransmission limit over each hop. Numerical results demonstrate that the path configuration methods can either significantly reduce the average energy consumption per packet delivery or considerably extend the average lifetime of the multihop route.
Borsato, Riccardo; Sfondrini, Alessandro; Stefanski, Bogdan; Torrielli, Alessandro
2013-01-01
We determine the all-loop dressing phases of the AdS3/CFT2 integrable system related to type IIB string theory on AdS3 x S3 x T4 by solving the recently found crossing relations and studying their singularity structure. The two resulting phases present a novel structure with respect to the ones appearing in AdS5/CFT4 and AdS4/CFT3. In the strongly-coupled regime, their leading order reduces to the universal Arutyunov-Frolov-Staudacher phase as expected. We also compute their sub-leading order and compare it with recent one-loop perturbative results, and co
Borsato, Riccardo; Ohlsson Sax, Olof; Sfondrini, Alessandro; Stefański, Bogdan, Jr.; Torrielli, Alessandro
2013-09-01
We determine the all-loop dressing phases of the AdS3/CFT2 integrable system related to type IIB string theory on AdS3×S3×T4 by solving the recently found crossing relations and studying their singularity structure. The two resulting phases present a novel structure with respect to the ones appearing in AdS5/CFT4 and AdS4/CFT3. In the strongly coupled regime, their leading order reduces to the universal Arutyunov-Frolov-Staudacher phase as expected. We also compute their subleading order and compare it with recent one-loop perturbative results and comment on their weak-coupling expansion.
Chaos and hydrodynamics near AdS$_2$
Jensen, Kristan
2016-01-01
We revisit AdS$_2$ holography with the Sachdev-Ye-Kitaev models in mind. Our main result is to rewrite a generic theory of gravity near an AdS$_2$ throat as a novel hydrodynamics coupled to the correlation functions of a conformal quantum mechanics. This gives a prescription for the computation of $n$-point functions in the dual quantum mechanics. We thereby find that the dual is maximally chaotic.
Quantum Field Theory and Unification in AdS5
Randall, Lisa; Randall, Lisa; Schwartz, Matthew D.
2001-01-01
We consider gauge bosons in the bulk of AdS5 in a two-brane theory that addresses the hierarchy problem. We show such a theory can be consistent with gauge coupling unification at a high scale. We discuss subtleties in this calculation and show how to regulate consistently in a bounded AdS5 background. Our regularization is guided by the holographic dual of the calculation.
Supersymmetry of AdS and flat IIB backgrounds
Beck, S.; Gutowski, J.; Papadopoulos, G.
2015-02-01
We present a systematic description of all warped AdS n × w M 10- n and IIB backgrounds and identify the a priori number of supersymmetries N preserved by these solutions. In particular, we find that the AdS n backgrounds preserve for n ≤ 4 and for 4 < n ≤ 6 supersymmetries and for suitably restricted. In addition under some assumptions required for the applicability of the maximum principle, we demonstrate that the Killing spinors of AdS n backgrounds can be identified with the zero modes of Dirac-like operators on M 10- n establishing a new class of Lichnerowicz type theorems. Furthermore, we adapt some of these results to backgrounds with fluxes by taking the AdS radius to infinity. We find that these backgrounds preserve for 2 < n ≤ 4 and for 4 < n ≤ 7 supersymmetries. We also demonstrate that the Killing spinors of AdS n × w M 10- n do not factorize into Killing spinors on AdS n and Killing spinors on M 10- n .
Action growth for AdS black holes
Cai, Rong-Gen; Ruan, Shan-Ming; Wang, Shao-Jiang; Yang, Run-Qiu; Peng, Rong-Hui
2016-09-01
Recently a Complexity-Action (CA) duality conjecture has been proposed, which relates the quantum complexity of a holographic boundary state to the action of a Wheeler-DeWitt (WDW) patch in the anti-de Sitter (AdS) bulk. In this paper we further investigate the duality conjecture for stationary AdS black holes and derive some exact results for the growth rate of action within the Wheeler-DeWitt (WDW) patch at late time approximation, which is supposed to be dual to the growth rate of quantum complexity of holographic state. Based on the results from the general D-dimensional Reissner-Nordström (RN)-AdS black hole, rotating/charged Bañados-Teitelboim-Zanelli (BTZ) black hole, Kerr-AdS black hole and charged Gauss-Bonnet-AdS black hole, we present a universal formula for the action growth expressed in terms of some thermodynamical quantities associated with the outer and inner horizons of the AdS black holes. And we leave the conjecture unchanged that the stationary AdS black hole in Einstein gravity is the fastest computer in nature.
Complexity Growth for AdS Black Holes
Cai, Rong-Gen; Wang, Shao-Jiang; Yang, Run-Qiu; Peng, Rong-Hui
2016-01-01
We further investigate the Complexity-Action (CA) duality conjecture for stationary anti de-Sitter (AdS) black holes and derive some exact results for the growth rate of action within Wheeler-DeWitt (WDW) patch at late time approximation, which is dual to the growth rate of quantum complexity of holographic state. Based on the results from the general $D$-dimensional Reissner-Nordstr\\"{o}m (RN)-AdS black hole, rotating/charged Ba\\~{n}ados-Teitelboim-Zanelli (BTZ) black hole, Kerr-AdS black hole and charged Gauss-Bonnet-AdS black hole, we present a new complexity bound but leave unchanged the conjecture that the stationary AdS black hole in Einstein gravity is the fastest computer in nature.
AdS_5 Black Holes with Fermionic Hair
Burrington, B A; Sabra, W A; Burrington, Benjamin A.; Liu, James T.
2004-01-01
The study of new BPS objects in AdS_5 has led to a deeper understanding of AdS/CFT. To help complete this picture, and to fully explore the consequences of the supersymmetry algebra, it is also important to obtain new solutions with bulk fermions turned on. In this paper we construct superpartners of the 1/2 BPS black hole in AdS_5 using a natural set of fermion zero modes. We demonstrate that these superpartners, carrying fermionic hair, have conserved charges differing from the original bosonic counterpart. To do so, we find the R-charge and dipole moment of the new system, as well as the mass and angular momentum, defined through the boundary stress tensor. The complete set of superpartners fits nicely into a chiral representation of AdS_5 supersymmetry, and the spinning solutions have the expected gyromagnetic ratio, g=1.
Constructing the AdS dual of a Fermi liquid: AdS Black holes with Dirac hair
\\vCubrović, Mihailo; Schalm, Koenraad
2010-01-01
We provide new evidence that the holographic dual to a strongly coupled charged Fermi Liquid has a non-zero fermion density in the bulk. We show that the pole-strength of the stable quasiparticle characterizing the Fermi surface is encoded in the spatially averaged AdS probability density of a single normalizable fermion wavefunction in AdS. Recalling Migdal's theorem which relates the pole strength to the Fermi-Dirac characteristic discontinuity in the number density at $\\ome_F$, we conclude that the AdS dual of a Fermi liquid is described by occupied on-shell fermionic modes in AdS. Encoding the occupied levels in the total probability density of the fermion field directly, we show that an AdS Reissner-Nordstr\\"{o}m black hole in a theory with charged fermions has a critical temperature, at which the system undergoes a first-order transition to a black hole with a non-vanishing profile for the bulk fermion field. Thermodynamics and spectral analysis confirm that the solution with non-zero AdS fermion-profil...
Different views of AEGIS / AD-6 Experiment (AD facility) AD-6
Maximilien Brice
2012-01-01
Different views of AEGIS / AD-6 Experiment (AD facility) in July of 2012. The visible parts are the positron accumulator (blue structures on top of of the antiproton extraction line) and the 5T magnet which traps the antiprotons.
Global geometric properties of AdS space and the AdS/CFT correspondence
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
The Poisson kernels and relations between them for a massive scalar field in a unit ball Bn with Hua's metric and conformal flat metric are obtained by describing the Bn as a submanifold of an (n+1)-dimensional embedding space. Global geometric properties of the AdS space are discussed. We show that the(n+1)-dimensional AdS space AdSn+1 is isomorphic to RP1×Bn and boundary of the AdS is isomorphic to RP1×Sn-1. Bulk-boundary propagator and the AdS/CFT like correspondence are demonstrated based on these global geometric properties of the RP1×Bn.
Supporting Dynamic Ad hoc Collaboration Capabilities
Energy Technology Data Exchange (ETDEWEB)
Agarwal, Deborah A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Berket, Karlo [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
2003-07-14
Modern HENP experiments such as CMS and Atlas involve as many as 2000 collaborators around the world. Collaborations this large will be unable to meet often enough to support working closely together. Many of the tools currently available for collaboration focus on heavy-weight applications such as videoconferencing tools. While these are important, there is a more basic need for tools that support connecting physicists to work together on an ad hoc or continuous basis. Tools that support the day-to-day connectivity and underlying needs of a group of collaborators are important for providing light-weight, non-intrusive, and flexible ways to work collaboratively. Some example tools include messaging, file-sharing, and shared plot viewers. An important component of the environment is a scalable underlying communication framework. In this paper we will describe our current progress on building a dynamic and ad hoc collaboration environment and our vision for its evolution into a HENP collaboration environment.
Detailed ultraviolet asymptotics for AdS scalar field perturbations
Evnin, Oleg
2016-01-01
We present a range of methods suitable for accurate evaluation of the leading asymptotics for integrals of products of Jacobi polynomials in limits when the degrees of some or all polynomials inside the integral become large. The structures in question have recently emerged in the context of effective descriptions of small amplitude perturbations in anti-de Sitter (AdS) spacetime. The limit of high degree polynomials corresponds in this situation to effective interactions involving extreme short-wavelength modes, whose dynamics is crucial for the turbulent instabilities that determine the ultimate fate of small AdS perturbations. We explicitly apply the relevant asymptotic techniques to the case of a self-interacting probe scalar field in AdS and extract a detailed form of the leading large degree behavior, including closed form analytic expressions for the numerical coefficients appearing in the asymptotics.
Asymptotically AdS spacetimes with a timelike Kasner singularity
Ren, Jie
2016-07-01
Exact solutions to Einstein's equations for holographic models are presented and studied. The IR geometry has a timelike cousin of the Kasner singularity, which is the less generic case of the BKL (Belinski-Khalatnikov-Lifshitz) singularity, and the UV is asymptotically AdS. This solution describes a holographic RG flow between them. The solution's appearance is an interpolation between the planar AdS black hole and the AdS soliton. The causality constraint is always satisfied. The entanglement entropy and Wilson loops are discussed. The boundary condition for the current-current correlation function and the Laplacian in the IR is examined. There is no infalling wave in the IR, but instead, there is a normalizable solution in the IR. In a special case, a hyperscaling-violating geometry is obtained after a dimensional reduction.
Entanglement entropy for free scalar fields in AdS
Sugishita, Sotaro
2016-01-01
We compute entanglement entropy for free massive scalar fields in anti-de Sitter (AdS) space. The entangling surface is a minimal surface whose boundary is a sphere at the boundary of AdS. The entropy can be evaluated from the thermal free energy of the fields on a topological black hole by using the replica method. In odd-dimensional AdS, exact expressions of the Renyi entropy S_n are obtained for arbitrary n. We also evaluate 1-loop corrections coming from the scalar fields to holographic entanglement entropy. Applying the results, we compute the leading difference of entanglement entropy between two holographic CFTs related by a renormalization group flow triggered by a double trace deformation. The difference is proportional to the shift of a central charge under the flow.
Microstates at the boundary of AdS
Mathur, Samir D
2011-01-01
The bound states of the D1D5 brane system have a known gravitational description: flat asymptotics, an anti-de Sitter region, and a 'cap' ending the AdS region. We construct perturbations that correspond to the action of chiral algebra generators on Ramond ground states of D1D5 branes. Abstract arguments in the literature suggest that the perturbation should be pure gauge in the AdS region; our perturbation indeed has this structure, with the nontrivial deformation of the geometry occurring at the 'neck' between the AdS region and asymptotic infinity. This 'non-gauge' deformation is needed to provide the nonzero energy and momentum carried by the perturbation. We also suggest implications this structure may have for the majority of microstates which live at the cap.
Revisiting the thermodynamic relations in AdS /CMT models
Hyun, Seungjoon; Park, Sang-A.; Yi, Sang-Heon
2017-03-01
Motivated by the recent unified approach to the Smarr-like relation of anti-de Sitter (AdS) planar black holes in conjunction with the quasilocal formalism on conserved charges, we revisit the quantum statistical and thermodynamic relations of hairy AdS planar black holes. By extending the previous results, we identify the hairy contribution in the bulk and show that the holographic computation can be improved so that it is consistent with the bulk computation. We argue that the first law can be retained in its universal form and that the relation between the on-shell renormalized Euclidean action and its free energy interpretation in gravity may also be undeformed even with the hairy contribution in hairy AdS black holes.
Diffusion and Chaos from near AdS$_2$ horizons
Blake, Mike
2016-01-01
We calculate the thermal diffusivity $D = \\kappa/c_{\\rho}$ and butterfly velocity $v_B$ in holographic models that flow to AdS$_2 \\times R^{d}$ fixed points in the infra-red. We show that both these quantities are governed by the same irrelevant deformation of AdS$_2$ and hence establish a simple relationship between them. When this deformation corresponds to a universal dilaton mode of dimension $\\Delta = 2$ then this relationship is always given by $D = v_B^2/(2 \\pi T)$.
An $xp$ model on $AdS_2$ spacetime
2012-01-01
In this paper we formulate the $xp$ model on the AdS$_2$ spacetime. We find that the spectrum of the Hamiltonian has positive and negative eigenvalues, whose absolute values are given by a harmonic oscillator spectrum, which in turn coincides with that of a massive Dirac fermion in AdS$_2$. We extend this result to generic $xp$ models which are shown to be equivalent to a massive Dirac fermion on spacetimes whose metric depend of the $xp$ Hamiltonian. Finally, we construct the generators of t...
Di Dato, Adriana
2014-01-01
We derive a map between Einstein spaces of positive and negative curvature. Starting from a space of positive curvature with some dimensions compactified on a sphere and analytically continuing the number of compact dimensions, we obtain a space of negative curvature with a compact hyperbolic subspace, and vice versa. Prime examples of such spaces are de Sitter and Anti-de Sitter space, as well as black hole spacetimes with (A)dS asymptotics and perturbed versions thereof, which play an important role in holography. This map extends work done by Caldarelli et.al., who map asymptotically AdS spaces to Ricci-flat ones. A remarkable result is that the boundary of asymptotically AdS spaces is mapped to a brane in the bulk of de Sitter, and perturbations near the AdS boundary are sourced by a stress tensor confined to this brane. We also calculate the Brown-York stress tensor for the perturbed AdS metric, which turns out to be the negative of the stress tensor on the de Sitter brane.
Trust Propagation in Small Worlds
DEFF Research Database (Denmark)
Gray, Elizabeth; Seigneur, Jean-Marc; Chen, Yong
2003-01-01
The possibility of a massive, networked infrastructure of diverse entities partaking in collaborative applications with each other increases more and more with the proliferation of mobile devices and the development of ad hoc networking technologies. In this context, traditional security measures...... do not scale well. We aim to develop trust-based security mechanisms using small world concepts to optimise formation and propagation of trust amongst entities in these vast networks. In this regard, we surmise that in a very large mobile ad hoc network, trust, risk, and recommendations can...
Penrose inequality for asymptotically AdS spaces
Energy Technology Data Exchange (ETDEWEB)
Itkin, Igor [Raymond and Beverly Sackler School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978 (Israel); Oz, Yaron, E-mail: yaronoz@post.tau.ac.il [Raymond and Beverly Sackler School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978 (Israel)
2012-02-28
In general relativity, the Penrose inequality relates the mass and the entropy associated with a gravitational background. If the inequality is violated by an initial Cauchy data, it suggests a creation of a naked singularity, thus providing means to consider the cosmic censorship hypothesis. We propose a general form of Penrose inequality for asymptotically locally AdS spaces.
Internet Advertising. Google AdWords versus Facebook Ads
Directory of Open Access Journals (Sweden)
Paul PAŞCU
2014-05-01
Full Text Available This article describes how to use the applications for Internet advertising, Google AdWords and Facebook Ads. Our attempt is to present the advantages and disadvantages of each of them, the costs and benefits, a useful aspect for companies that plan to start advertising campaigns on the Internet.
Energy Technology Data Exchange (ETDEWEB)
1994-12-01
RAMSGAS, the Research and Development Analysis Modeling System World Natural Gas Model, was developed to support planning of unconventional gaseoues fuels research and development. The model is a scenario analysis tool that can simulate the penetration of unconventional gas into world markets for oil and gas. Given a set of parameter values, the model estimates the natural gas supply and demand for the world for the period from 1980 to 2030. RAMSGAS is based on a supply/demand framwork and also accounts for the non-renewable nature of gas resources. The model has three fundamental components: a demand module, a wellhead production cost module, and a supply/demand interface module. The demand for gas is a product of total demand for oil and gas in each of 9 demand regions and the gas share. Demand for oil and gas is forecast from the base year of 1980 through 2030 for each demand region, based on energy growth rates and price-induced conservation. For each of 11 conventional and 19 unconventional gas supply regions, wellhead production costs are calculated. To these are added transportation and distribution costs estimates associated with moving gas from the supply region to each of the demand regions and any economic rents. Based on a weighted average of these costs and the world price of oil, fuel shares for gas and oil are computed for each demand region. The gas demand is the gas fuel share multiplied by the total demand for oil plus gas. This demand is then met from the available supply regions in inverse proportion to the cost of gas from each region. The user has almost complete control over the cost estimates for each unconventional gas source in each year and thus can compare contributions from unconventional resources under different cost/price/demand scenarios.
Directory of Open Access Journals (Sweden)
Yawu Liu
Full Text Available To compare the accuracies of predicting AD conversion by using a decision support system (PredictAD tool and current research criteria of prodromal AD as identified by combinations of episodic memory impairment of hippocampal type and visual assessment of medial temporal lobe atrophy (MTA on MRI and CSF biomarkers.Altogether 391 MCI cases (158 AD converters were selected from the ADNI cohort. All the cases had baseline cognitive tests, MRI and/or CSF levels of Aβ1-42 and Tau. Using baseline data, the status of MCI patients (AD or MCI three years later was predicted using current diagnostic research guidelines and the PredictAD software tool designed for supporting clinical diagnostics. The data used were 1 clinical criteria for episodic memory loss of the hippocampal type, 2 visual MTA, 3 positive CSF markers, 4 their combinations, and 5 when the PredictAD tool was applied, automatically computed MRI measures were used instead of the visual MTA results. The accuracies of diagnosis were evaluated with the diagnosis made 3 years later.The PredictAD tool achieved the overall accuracy of 72% (sensitivity 73%, specificity 71% in predicting the AD diagnosis. The corresponding number for a clinician's prediction with the assistance of the PredictAD tool was 71% (sensitivity 75%, specificity 68%. Diagnosis with the PredictAD tool was significantly better than diagnosis by biomarkers alone or the combinations of clinical diagnosis of hippocampal pattern for the memory loss and biomarkers (p≤0.037.With the assistance of PredictAD tool, the clinician can predict AD conversion more accurately than the current diagnostic criteria.
AdS5 backgrounds with 24 supersymmetries
Beck, S.; Gutowski, J.; Papadopoulos, G.
2016-06-01
We prove a non-existence theorem for smooth AdS 5 solutions with connected, compact without boundary internal space that preserve strictly 24 supersymmetries. In particular, we show that D = 11 supergravity does not admit such solutions, and that all such solutions of IIB supergravity are locally isometric to the AdS 5 × S 5 maximally supersymmetric background. Furthermore, we prove that (massive) IIA supergravity also does not admit such solutions, provided that the homogeneity conjecture for massive IIA supergravity is valid. In the context of AdS/CFT these results imply that if gravitational duals for strictly mathcal{N}=3 superconformal theories in 4-dimensions exist, they are either singular or their internal spaces are not compact.
Coset construction of AdS particle dynamics
Heinze, Martin; Megrelidze, Luka
2016-01-01
We analyze dynamics of the AdS$_{N+1}$ particle realized on the coset SO$(2,N)/$SO$(1,N)$. Hamiltonian reduction provides the physical phase space in terms of the coadjoint orbit obtained by boosting a timelike element of ${\\frak so}(2,N)$. We show equivalence of this approach to geometric quantization and to the SO$(N)$ covariant oscillator description, for which the boost generators entail a complicated operator ordering. As an alternative scheme, we introduce dual oscillator variables and derive their algebra at the classical and the quantum level. This simplifies the calculations of the commutators for the boost generators and leads to unitary irreducible representations of ${\\frak so}(2,N)$ for all admissible values of the mass parameter. We furthermore discuss a SO$(N)$ covariant supersymmetric extensions of the oscillator quantization, with its realization for superparticles in AdS$_2$ and AdS$_3$ given by recent works.
Sub-AdS Scale Locality in AdS$_3$/CFT$_2$
Belin, Alexandre; Jefferson, Robert A; Kabir, Laurens
2016-01-01
We investigate sub-AdS scale locality in a weakly coupled toy model of the AdS$_3$/CFT$_2$ correspondence. We find that this simple model has the correct density of states at low and high energies to be dual to Einstein gravity coupled to matter in AdS$_3$. Bulk correlation functions also have the correct behavior at leading order in the large $N$ expansion, but non-local effects emerge at order $1/N$. Our analysis leads to the conjecture that any large $N$ CFT$_2$ that is modular invariant and has the right low-energy density of states is dual to a gravitational theory with sub-AdS scale locality.
Ultraviolet asymptotics for quasiperiodic AdS_4 perturbations
Craps, Ben; Jai-akson, Puttarak; Vanhoof, Joris
2015-01-01
Spherically symmetric perturbations in AdS-scalar field systems of small amplitude epsilon approximately periodic on time scales of order 1/epsilon^2 (in the sense that no significant transfer of energy between the AdS normal modes occurs) have played an important role in considerations of AdS stability. They are seen as anchors of stability islands where collapse of small perturbations to black holes does not occur. (This collapse, if it happens, typically develops on time scales of the order 1/epsilon^2.) We construct an analytic treatment of the frequency spectra of such quasiperiodic perturbations, paying special attention to the large frequency asymptotics. For the case of a self-interacting phi^4 scalar field in a non-dynamical AdS background, we arrive at a fairly complete analytic picture involving quasiperiodic spectra with an exponential suppression modulated by a power law at large mode numbers. For the case of dynamical gravity, the structure of the large frequency asymptotics is more complicated....
Kolmogorov-Zakharov spectrum in AdS gravitational collapse.
de Oliveira, H P; Pando Zayas, Leopoldo A; Rodrigues, E L
2013-08-01
We study black hole formation during the gravitational collapse of a massless scalar field in asymptotically D-dimensional anti-de Sitter AdS(D) spacetimes for D = 4, 5. We conclude that spherically symmetric gravitational collapse in asymptotically AdS spaces is turbulent and characterized by a Kolmogorov-Zakharov spectrum. Namely, we find that after an initial period of weakly nonlinear evolution, there is a regime where the power spectrum of the Ricci scalar evolves as ω(-s) with the frequency, ω, and s ≈ 1.7 ± 0.1.
Thermodynamics of Einstein-Proca AdS Black Holes
Liu, Hai-Shan; Pope, C N
2014-01-01
We study static spherically-symmetric solutions of the Einstein-Proca equations in the presence of a negative cosmological constant. We show that the theory admits solutions describing both black holes and also solitons in an asymptotically AdS background. Interesting subtleties can arise in the computation of the mass of the solutions and also in the derivation of the first law of thermodynamics. We make use of holographic renormalisation in order to calculate the mass, even in cases where the solutions have a rather slow approach to the asymptotic AdS geometry. By using the procedure developed by Wald, we derive the first law of thermodynamics for the black hole and soliton solutions. This includes a non-trivial contribution associated with the Proca "charge." The solutions cannot be found analytically, and so we make use of numerical integration techniques to demonstrate their existence.
Universal isolation in the AdS landscape
Danielsson, U H; Vargas, S C
2016-01-01
We study the universal conditions for quantum non-perturbative stability against bubble nucleation for pertubatively stable AdS vacua based on positive energy theorems. We also compare our analysis with the pre-existing ones in the literature carried out within the thin-wall approximation. The aforementioned criterion is then tested in two explicit examples describing massive type IIA string theory compactified on $S^3$ and $S^3\\,\\times\\,S^3$, respectively. The AdS landscape of both classes of compactifications is known to consist of a set of isolated points. The main result is that all critical points respecting the Breitenlohner-Freedaman (BF) bound also turn out be stable at a non-perturbative level. Finally, we speculate on the possible universal features that may be extracted from the above specific examples.
Perturbative entanglement thermodynamics for AdS spacetime: Renormalization
Mishra, Rohit
2015-01-01
We study the effect of charged excitations in the AdS spacetime on the first law of entanglement thermodynamics. It is found that `boosted' AdS black holes give rise to a more general form of first law which includes chemical potential and charge density. To obtain this result we have to resort to a second order perturbative calculation of entanglement entropy for small size subsystems. At first order the form of entanglement law remains unchanged even in the presence of charged excitations. But the thermodynamic quantities have to be appropriately `renormalized' at the second order due to the corrections. We work in the perturbative regime where $T_{thermal}\\ll T_E$.
The Mixed Phase of Charged AdS Black Holes
Directory of Open Access Journals (Sweden)
Piyabut Burikham
2016-01-01
Full Text Available We study the mixed phase of charged AdS black hole and radiation when the total energy is fixed below the threshold to produce a stable charged black hole branch. The coexistence conditions for the charged AdS black hole and radiation are derived for the generic case when radiation particles carry charge. The phase diagram of the mixed phase is demonstrated for both fixed potential and charge ensemble. In the dual gauge picture, they correspond to the mixed phase of quark-gluon plasma (QGP and hadron gas in the fixed chemical potential and density ensemble, respectively. In the nuclei and heavy-ion collisions at intermediate energies, the mixed phase of exotic QGP and hadron gas could be produced. The mixed phase will condense and evaporate into the hadron gas as the fireball expands.
Note on classical string dynamics on AdS3
Bañados, Máximo; Ritz, Adam
1999-12-01
We consider bosonic strings propagating on Euclidean anti-de Sitter space (AdS3), and study in particular the realization of various worldsheet symmetries. We give a proper definition for the Brown-Henneaux asymptotic target space symmetry, when acting on the string action, and derive the Giveon-Kutasov-Seiberg worldsheet contour integral representation simply by using Noether's theorem. We show that making identifications in the target space is equivalent to the insertion of an (exponentiated) graviton vertex operator carrying the corresponding charge. Finally, we point out an interesting relation between 3D gravity and the dynamics of the worldsheet on AdS3. Both theories are described by an SL(2,C)/SU(2) Wess-Zumino-Witten (WZW) model, and we prove that the reduction conditions determined on one hand by worldsheet diffeomorphism invariance, and on the other by the Brown-Henneaux boundary conditions, are the same.
Observing quantum gravity in asymptotically AdS space
Emelyanov, Slava
2015-12-01
The question is studied of whether an observer can discover quantum gravity in the semiclassical regime. It is shown that it is indeed possible to probe a certain quantum gravity effect by employing an appropriately designed detector. The effect is related to the possibility of having topologically inequivalent geometries in the path-integral approach at the same time. A conformal field theory (CFT) state which is expected to describe the eternal anti-de Sitter (AdS) black hole in the large-N limit is discussed. It is argued under certain assumptions that the black hole boundary should be merely a patch of the entire AdS boundary. This leads then to a conclusion that that CFT state is the ordinary CFT vacuum restricted to that patch. If existent, the bulk CFT operators can behave as the ordinary semiclassical quantum field theory in the large-N limit in the weak sense.
Universal isolation in the AdS landscape
Danielsson, U. H.; Dibitetto, G.; Vargas, S. C.
2016-12-01
We study the universal conditions for quantum nonperturbative stability against bubble nucleation for pertubatively stable AdS vacua based on positive energy theorems. We also compare our analysis with the preexisting ones in the literature carried out within the thin-wall approximation. The aforementioned criterion is then tested in two explicit examples describing massive type IIA string theory compactified on S3 and S3×S3, respectively. The AdS landscape of both classes of compactifications is known to consist of a set of isolated points. The main result is that all critical points respecting the Breitenlohner-Freedman (BF) bound also turn out be stable at a nonperturbative level. Finally, we speculate on the possible universal features that may be extracted from the above specific examples.
Smoothed Transitions in Higher Spin AdS Gravity
Banerjee, Shamik; Hellerman, Simeon; Hijano, Eliot; Lepage-Jutier, Arnaud; Maloney, Alexander; Shenker, Stephen
2012-01-01
We consider CFTs conjectured to be dual to higher spin theories of gravity in AdS_3 and AdS_4. Two dimensional CFTs with W_N symmetry are considered in the lambda=0 (k --> infinity) limit, where they are conjectured to be described by continuous orbifolds. The torus partition function is computed, using reasonable assumptions, and equals that of a free field theory. We find no phase transition at temperatures of order one; the usual Hawking-Page phase transition is removed by the highly degenerate light states associated with conical defect states in the bulk. Three dimensional Chern-Simons-matter CFTs with vector-like matter are considered on T^3, where the dynamics is described by an effective theory for the eigenvalues of the holonomies. Likewise, we find no evidence for a Hawking-Page phase transition at large level k.
N=2 supersymmetric sigma-models in AdS
Butter, Daniel
2011-01-01
We construct the most general N=2 supersymmetric nonlinear sigma-model in four-dimensional anti-de Sitter (AdS) space in terms of N=1 chiral superfields. The target space is shown to be a non-compact hyperkahler manifold restricted to possess a special Killing vector field. A remarkable property of the sigma-model constructed is that the algebra of OSp(2|4) transformations is closed off the mass shell.
N=2 AdS supergravity and supercurrents
Butter, Daniel
2011-01-01
We consider the minimal off-shell formulation for four-dimensional N=2 supergravity with a cosmological term, in which the second compensator is an improved tensor multiplet. We use it to derive a linearized supergravity action (and its dual versions) around the anti-de Sitter (AdS) background in terms of three N=2 off-shell multiplets: an unconstrained scalar superfield, vector and tensor multiplets. This allows us to deduce the structure of the supercurrent multiplet associated with those supersymmetric theories which naturally couple to the supergravity formulation chosen, with or without a cosmological term. Finally, our linearized N=2 AdS supergravity action is reduced to N=1 superspace. The result is a sum of two N=1 linearized actions describing (i) old minimal supergravity; and (ii) an off-shell massless gravitino multiplet. We also derive dual formulations for the massless N=1 gravitino multiplet in AdS. As a by-product of our consideration, we derive the consistent supergravity extension of the N=1 ...
World Knowledge in Computational Models of Discourse Comprehension
Frank, Stefan L.; Koppen, Mathieu; Noordman, Leo G. M.; Vonk, Wietske
2008-01-01
Because higher level cognitive processes generally involve the use of world knowledge, computational models of these processes require the implementation of a knowledge base. This article identifies and discusses 4 strategies for dealing with world knowledge in computational models: disregarding world knowledge, "ad hoc" selection, extraction from…
Intellectual mobile Ad Hoc networks
Sova, Oleg; Romanjuk, Valeriy; Bunin, Sergey; Zhuk, Pavlo
2012-01-01
In this article intellectualization of Mobile Ad Hoc Networks resources management is offered. It was proposed decomposition of the primary goal of MANET functioning into easy subgoals, and fragment of the MANET node target structure is presented.
Cosmological Solutions on Compactified AdS_5 with a Thermal Bulk
Rothstein, I Z
2001-01-01
This paper is an investigation of the effects of a thermal bulk fluid in brane world models compactified on AdS_5. Our primary purpose is to study how such a fluid changes the bulk dynamics and to compare these effects with those generated by matter localized to the branes. We find an exact cosmological solution for a thermally excited massless bulk field, as well as perturbative solutions with matter on the brane and in the bulk. We then perturb around these solutions to find solutions for a massive bulk mode in the limit where the bulk mass (m_B) is small compared to the AdS curvature scale and T< m_B. We find that without a stabilizing potential there are no physical solutions for a thermal bulk fluid. We then include a stabilizing potential and calculate the shift in the radion as well as the time dependence of the weak scale as a function of the bulk mass. It is shown that, as opposed to a brane fluid, the bulk fluid contribution to the bulk dynamics is controlled by the bulk mass.
Resurgence of the dressing phase for ${\\rm AdS}_5\\times {\\rm S}^5$
Arutyunov, Gleb; Savin, Sergei
2016-01-01
We discuss the resummation of the strong coupling asymptotic expansion of the dressing phase of the ${\\rm AdS}_5\\times {\\rm S}^5$ superstring. The dressing phase proposed by Beisert, Eden and Staudacher can be recovered from a modified Borel-Ecalle resummation of this asymptotic expansion only by completing it with new, non-perturbative and exponentially suppressed terms that can be organized into different sectors labelled by an instanton-like number. We compute the contribution to the dressing phase coming from the sum over all the instanton sectors and show that it satisfies the homogeneous crossing symmetry equation. We comment on the semiclassical origin of the non-perturbative terms from the world-sheet theory point of view even though their precise explanation remains still quite mysterious.
Resurgence of the dressing phase for AdS5 × S5
Arutyunov, Gleb; Dorigoni, Daniele; Savin, Sergei
2017-01-01
We discuss the resummation of the strong coupling asymptotic expansion of the dressing phase of the AdS5 × S5 superstring. The dressing phase proposed by Beisert, Eden and Staudacher can be recovered from a modified Borel-Ecalle resummation of this asymptotic expansion only by completing it with new, non-perturbative and exponentially suppressed terms that can be organized into different sectors labelled by an instanton-like number. We compute the contribution to the dressing phase coming from the sum over all the instanton sectors and show that it satisfies the homogeneous crossing symmetry equation. We comment on the semiclassical origin of the non-perturbative terms from the world-sheet theory point of view even though their precise explanation remains still quite mysterious.
Supergravity one-loop corrections on AdS7 and AdS3, higher spins and AdS/CFT
Directory of Open Access Journals (Sweden)
Matteo Beccaria
2015-03-01
Full Text Available As was shown earlier, the one-loop correction in 10d supergravity on AdS5×S5 corresponds to the contributions to the vacuum energy and 4d boundary conformal anomaly which are minus the values for one N=4 Maxwell supermultiplet, thus reproducing the subleading term in the N2−1 coefficient in the dual SU(N SYM theory. We perform similar one-loop computations in 11d supergravity on AdS7×S4 and 10d supergravity on AdS3×S3×T4. In the AdS7 case we find that the corrections to the 6d conformal anomaly a-coefficient and the vacuum energy are again minus the ones for one (2,0 tensor multiplet, suggesting that the total a-anomaly coefficient for the dual (2,0 theory is 4N3−9/4N−7/4 and thus vanishes for N=1. In the AdS3 case the one-loop correction to the vacuum energy or 2d central charge turns out to be equal to that of one free (4,4 scalar multiplet, i.e. is c=+6. This reproduces the subleading term in the central charge c=6(Q1Q5+1 of the dual 2d CFT describing decoupling limit of D5–D1 system. We also present the expressions for the 6d a-anomaly coefficient and vacuum energy contributions of general-symmetry higher spin field in AdS7 and consider their application to tests of vectorial AdS/CFT with the boundary conformal 6d theory represented by free scalars, spinors or rank-2 antisymmetric tensors.
Entanglement Temperature and Perturbed AdS$_3$ Geometry
Levine, Gregory
2015-01-01
In analogy to the first law of thermodynamics, the increase in entanglement entropy $\\delta S$ of a conformal field theory (CFT) is proportional to the increase in energy, $\\delta E$, of the subsystem divided by an effective entanglement temperature, $T_E$. Extending this analogy, we study entanglement entropy when the subsystem is perturbed by applying an external field, expressed as a coupling to a local marginal operator in the CFT. We show that the resulting entropy change is associated with a change in the entanglement temperature itself, leading to an equation analogous to the Clausius relation. Using AdS/CFT duality we develop a relationship between a perturbation in the local entanglement temperature, $\\delta T_E(x)$ of the CFT and the perturbation of the bulk AdS metric. Using the AdS$_3$ minimal surface as a probe, we can construct bulk metric perturbations from an exact numerical computation of the entanglement temperature in a two dimensional $c=1$ boundary theory deformed by a marginal perturbati...
AdS Chern-Simons Gravity induces Conformal Gravity
Aros, Rodrigo
2013-01-01
The leitmotif of this paper is the question of whether four- and higher even-dimensional Conformal Gravities do have a Chern-Simons pedigree. We show that Weyl gravity can be obtained as dimensional reduction of a five-dimensional Chern-Simons action for a suitable (gauged-fixed, tractor-like) five-dimensional AdS connection. The gauge-fixing and dimensional reduction program admits a readily generalization to higher dimensions for the case of certain conformal gravities obtained by contractions of the Weyl tensor.
Reentrant Phase Transitions in Rotating AdS Black Holes
Altamirano, Natacha; Mann, Robert B
2013-01-01
We study the thermodynamics of higher-dimensional singly spinning asymptotically AdS black holes in the canonical (fixed J) ensemble of extended phase space, where the cosmological constant is treated as pressure and the corresponding conjugate quantity is interpreted as thermodynamic volume. Along with the usual small/large black hole phase transition, we find a new phenomenon of reentrant phase transitions for all d>5 dimensions, in which a monotonic variation of the temperature yields two phase transitions from large to small and back to large black holes. This situation is similar to that seen in multicomponent liquids.
Internal Structure of Charged AdS Black Holes
Bhattacharjee, Srijit; Virmani, Amitabh
2016-01-01
When an electrically charged black hole is perturbed its inner horizon becomes a singularity, often referred to as the Poisson-Israel mass inflation singularity. Ori constructed a model of this phenomenon for asymptotically flat black holes, in which the metric can be determined explicitly in the mass inflation region. In this paper we implement the Ori model for charged AdS black holes. We find that the mass function inflates faster than the flat space case as the inner horizon is approached. Nevertheless, the mass inflation singularity is still a weak singularity: although spacetime curvature becomes infinite, tidal distortions remain finite on physical objects attempting to cross it.
Duality invariance of s≥32 fermions in AdS
Directory of Open Access Journals (Sweden)
S. Deser
2014-11-01
Full Text Available We show that in D=4 AdS, s≥3/2 partially massless (PM fermions retain the duality invariances of their flat space massless counterparts. They have tuned ratios m2/M2≠0 that turn them into sums of effectively massless unconstrained helicity ±(s,⋯,32 excitations, shorn of the lowest (non-dual helicity ±12-rung and — more generally — of succeeding higher rung as well. Each helicity mode is separately duality invariant, like its flat space counterpart.
M-Theory solutions with AdS factors
Gauntlett, J P; Pakis, S; Waldram, D; Gauntlett, Jerome P.; Kim, Nakwoo; Pakis, Stathis; Waldram, Daniel
2002-01-01
Solutions of D=7 maximal gauged supergravity are constructed with metrics that are a product of a n-dimensional anti-de Sitter (AdS) space, with n=2,3,4,5, and certain Einstein manifolds. The gauge fields have the same form as in the recently constructed solutions describing the near-horizon limits of M5-branes wrapping supersymmetric cycles. The new solutions do not preserve any supersymmetry and can be uplifted to obtain new solutions of D=11 supergravity, which are warped and twisted products of the D=7 metric with a squashed four-sphere. Some aspects of the stability of the solutions are discussed.
M-theory solutions with AdS factors
Energy Technology Data Exchange (ETDEWEB)
Gauntlett, Jerome P [Department of Physics, Queen Mary, University of London, Mile End Road, London E1 4NS (United Kingdom); Kim, Nakwoo [Max-Planck-Institut fuer Gravitationsphysik, Albert-Einstein-Institut, Am Muehlenberg 1, D-14476 Golm (Germany); Pakis, Stathis [Department of Physics, Queen Mary, University of London, Mile End Road, London E1 4NS (United Kingdom); Waldram, Daniel [Department of Physics, Queen Mary, University of London, Mile End Road, London E1 4NS (United Kingdom)
2002-08-07
Solutions of D=7 maximal gauged supergravity are constructed with metrics that are a product of an n-dimensional anti-de Sitter (AdS) space, with n=2, 3, 4, 5, and certain Einstein manifolds. The gauge fields have the same form as in the recently constructed solutions describing the near-horizon limits of M5-branes wrapping supersymmetric cycles. The new solutions do not preserve any supersymmetry and can be uplifted to obtain new solutions of D=11 supergravity, which are warped and twisted products of the D=7 metric with a squashed four-sphere. Some aspects of the stability of the solutions are discussed.
Most general AdS_3 boundary conditions
Grumiller, Daniel
2016-01-01
We consider the most general asymptotically anti-de Sitter boundary conditions in three-dimensional Einstein gravity with negative cosmological constant. The metric contains in total twelve independent functions, six of which are interpreted as chemical potentials (or non-normalizable fluctuations) and the other half as canonical boundary charges (or normalizable fluctuations). Their presence modifies the usual Fefferman-Graham expansion. The asymptotic symmetry algebra consists of two sl(2)_k current algebras, the levels of which are given by k=l/(4G_N), where l is the AdS radius and G_N the three-dimensional Newton constant.
Coherent Cascade: Collapsing Solutions in Global AdS
Freivogel, Ben
2015-01-01
We analyze the gravitational dynamics of a classical scalar field that sometimes leads to blackhole formation in asymptotically AdS spacetime at the shortest nonlinear time scale. We present strong evidence that the dynamics is governed by a "coherent cascade", with all modes remaining in phase as the energy flows to higher frequencies into a power-law spectrum. Using a coherent phase ansatz, we analytically find these power-law solutions. We show how the particular power is determined by the scaling properties of the interaction coefficients. Our result agrees with existing numerical results in 4+1 dimensions, and makes predictions in higher dimensions.
Heavy quark potential from deformed AdS5 models
Zhang, Zi-qiang; Hou, De-fu; Chen, Gang
2017-04-01
In this paper, we investigate the heavy quark potential in some holographic QCD models. The calculation relies on a modified renormalization scheme mentioned in a previous work of Albacete et al. After studying the heavy quark potential in Pirner-Galow model and Andreev-Zakharov model, we extend the discussion to a general deformed AdS5 case. It is shown that the obtained potential is negative definite for all quark-antiquark separations, differs from that using the usual renormalization scheme.
Accomazzi, Alberto; Kurtz, M. J.; Henneken, E. A.; Grant, C. S.; Thompson, D.; Luker, J.; Chyla, R.; Murray, S. S.
2014-01-01
In the spring of 1993, the Smithsonian/NASA Astrophysics Data System (ADS) first launched its bibliographic search system. It was known then as the ADS Abstract Service, a component of the larger Astrophysics Data System effort which had developed an interoperable data system now seen as a precursor of the Virtual Observatory. As a result of the massive technological and sociological changes in the field of scholarly communication, the ADS is now completing the most ambitious technological upgrade in its twenty-year history. Code-named ADS 2.0, the new system features: an IT platform built on web and digital library standards; a new, extensible, industrial strength search engine; a public API with various access control capabilities; a set of applications supporting search, export, visualization, analysis; a collaborative, open source development model; and enhanced indexing of content which includes the full-text of astronomy and physics publications. The changes in the ADS platform affect all aspects of the system and its operations, including: the process through which data and metadata are harvested, curated and indexed; the interface and paradigm used for searching the database; and the follow-up analysis capabilities available to the users. This poster describes the choices behind the technical overhaul of the system, the technology stack used, and the opportunities which the upgrade is providing us with, namely gains in productivity and enhancements in our system capabilities.
Parikh, Maulik
2012-01-01
In anti-de Sitter space a highly accelerating observer perceives a Rindler horizon. The two Rindler wedges in AdS_{d+1} are holographically dual to an entangled conformal field theory that lives on two boundaries with geometry R x H_{d-1}. For AdS_3, the holographic duality is especially tractable, allowing quantum-gravitational aspects of Rindler horizons to be probed. We recover the thermodynamics of Rindler-AdS space directly from the boundary conformal field theory. We derive the temperature from the two-point function and obtain the Rindler entropy density precisely, including numerical factors, using the Cardy formula. We also probe the causal structure of the spacetime, and find from the behavior of the one-point function that the CFT "knows" when a source has fallen across the Rindler horizon. This is so even though, from the bulk point of view, there are no local signifiers of the presence of the horizon. Finally, we discuss an alternate foliation of Rindler-AdS which is dual to a CFT living in de Si...
AdS twistors for higher spin theory
Cederwall, M
2004-01-01
We construct spectra of supersymmetric higher spin theories in D=4, 5 and 7 from twistors describing massless (super-)particles on AdS spaces. A massless twistor transform is derived in a geometric way from classical kinematics. Relaxing the spin-shell constraints on twistor space gives an infinite tower of massless states of a ``higher spin particle'', generalising previous work of Bandos et al. This can generically be done in a number of ways, each defining the states of a distinct higher spin theory, and the method provides a systematic way of finding these. We reproduce known results in D=4, minimal supersymmetric 5- and 7-dimensional models, as well as supersymmetrisations of Vasiliev's Sp-models as special cases. In the latter models a dimensional enhancement takes place, meaning that the theory lives on a space of higher dimension than the original AdS space, and becomes a theory of doubletons. This talk was presented at the XIXth Max Born Symposium ``Fundamental Interactions and Twistor-Like Methods''...
AdCell: Ad Allocation in Cellular Networks
Alaei, Saeed; Liaghat, Vahid; Pei, Dan; Saha, Barna
2011-01-01
With more than four billion usage of cellular phones worldwide, mobile advertising has become an attractive alternative to online advertisements. In this paper, we propose a new targeted advertising policy for Wireless Service Providers (WSPs) via SMS or MMS- namely {\\em AdCell}. In our model, a WSP charges the advertisers for showing their ads. Each advertiser has a valuation for specific types of customers in various times and locations and has a limit on the maximum available budget. Each query is in the form of time and location and is associated with one individual customer. In order to achieve a non-intrusive delivery, only a limited number of ads can be sent to each customer. Recently, new services have been introduced that offer location-based advertising over cellular network that fit in our model (e.g., ShopAlerts by AT&T) . We consider both online and offline version of the AdCell problem and develop approximation algorithms with constant competitive ratio. For the online version, we assume tha...
Quantum cat map dynamics on AdS$_2$
Axenides, Minos; Nicolis, Stam
2016-01-01
We present a toy model for the chaotic unitary scattering of single particle wave packets on the radial AdS$_2$ geometry of extremal BH horizons. Based on our recent work for the discretization of the AdS$_2$ space-time, which describes a finite and random geometry, by modular arithmetic, we investigate the validity of the eigenstate thermalization hypothesis (ETH), as well as that of the fast scrambling time bound conjecture (STB), for an observer with time evolution operator the quantum Arnol'd cat map (QACM). We find that the QACM, while possessing a linear spectrum, has eigenstates, which can be expressed in closed form, are found to be random and to satisfy the assumptions of the ETH.The implications are that the dynamics is described by a chaotic, unitary, single particle S-matrix, which completely delocalizes and randomizes initial gaussian wave packets . Applying results obtained by Dyson and Falk for the periods of the Arnol'd Cat Map(ACM),which are related to its mixing time, we also find that the t...
Cassani, Davide; Marrani, Alessio; Morales, Jose F; Samtleben, Henning
2010-01-01
We apply the techniques of special Kaehler geometry to investigate AdS_4 vacua of general N=2 gauged supergravities underlying flux compactifications of type II theories. We formulate the scalar potential and its extremization conditions in terms of a triplet of prepotentials P_x and their special Kaehler covariant derivatives only, in a form that recalls the potential and the attractor equations of N=2 black holes. We propose a system of first order equations for the P_x which generalize the supersymmetry conditions and yield non-supersymmetric vacua. Special geometry allows us to recast these equations in algebraic form, and we find an infinite class of new N=0 and N=1 AdS_4 solutions, displaying a rich pattern of non-trivial charges associated with NSNS and RR fluxes. Finally, by explicit evaluation of the entropy function on the solutions, we derive a U-duality invariant expression for the cosmological constant and the central charges of the dual CFT's.
The CFT dual of AdS gravity with torsion
Klemm, Dietmar
2007-01-01
We consider the Mielke-Baekler model of three-dimensional AdS gravity with torsion, which has gravitational and translational Chern-Simons terms in addition to the usual Einstein-Hilbert action with cosmological constant. It is shown that the topological nature of the model leads to a finite Fefferman-Graham expansion. We derive the holographic stress tensor and the associated Ward identities and show that, due to the asymmetry of the left- and right-moving central charges, a Lorentz anomaly appears in the dual conformal field theory. Both the consistent and the covariant Weyl and Lorentz anomaly are determined, and the Wess-Zumino consistency conditions for the former are verified. Moreover we consider the most general solution with flat boundary geometry, which describes left-and right-moving gravitational waves on AdS_3 with torsion, and shew that in this case the holographic energy-momentum tensor is given by the wave profiles. The anomalous transformation laws of the wave profiles under diffeomorphisms p...
AdS nonlinear instability: moving beyond spherical symmetry
Dias, Óscar J. C.; Santos, Jorge E.
2016-12-01
Anti-de Sitter (AdS) is conjectured to be nonlinear unstable to a weakly turbulent mechanism that develops a cascade towards high frequencies, leading to black hole formation (Dafermos and Holzegel 2006 Seminar at DAMTP (University of Cambridge) available at https://dpmms.cam.ac.uk/~md384/ADSinstability.pdf, Bizon and Rostworowski 2011 Phys. Rev. Lett. 107 031102). We give evidence that the gravitational sector of perturbations behaves differently from the scalar one studied by Bizon and Rostworowski. In contrast with Bizon and Rostworowski, we find that not all gravitational normal modes of AdS can be nonlinearly extended into periodic horizonless smooth solutions of the Einstein equation. In particular, we show that even seeds with a single normal mode can develop secular resonances, unlike the spherically symmetric scalar field collapse studied by Bizon and Rostworowski. Moreover, if the seed has two normal modes, more than one resonance can be generated at third order, unlike the spherical collapse of Bizon and Rostworowski. We also show that weak turbulent perturbative theory predicts the existence of direct and inverse cascades, with the former dominating the latter for equal energy two-mode seeds.
Smooth Causal Patches for AdS Black Holes
Raju, Suvrat
2016-01-01
We review the paradox of low energy excitations about an AdS black hole. An appropriately chosen unitary operator in the boundary theory can create a locally strong excitation near the black hole horizon, whose global energy is small as a result of the gravitational redshift. The paradox is that this seems to violate a general rule of statistical mechanics, which states that an operator with energy parametrically smaller than $k T$ cannot create a significant excitation in a thermal system. When we carefully examine the position dependence of the boundary unitary operator that produces the excitation and the bulk observable necessary to detect the anomalously large effect, we find that they do not both fit in a single causal patch. This follows from a remarkable property of position space AdS correlators that we establish explicitly, and resolves the paradox in a generic state of the system, since no combination of observers can both create the excitation and observe its effect. As a special case of our analy...
Online Ad Slotting With Cancellations
Constantin, Florin; Muthukrishnan, S; Pal, Martin
2008-01-01
Many advertisers buy advertisements (ads) on the Internet or on traditional media and seek simple, online mechanisms to reserve ad slots in advance. Media publishers represent a vast and varying inventory, and they too seek automatic, online mechanisms for pricing and allocating such reservations. In this paper, we present and study a simple model for auctioning such ad slots in advance. Bidders arrive sequentially and report which slots they are interested in. The seller must decide immediately whether or not to grant a reservation. Our model allows a seller to accept reservations, but possibly cancel the allocations later and pay the bidder a cancellation compensation (bump payment). Our main result is an online mechanism to derive prices and bump payments that is efficient to implement. This mechanism has many desirable properties. It is individually rational; winners have an incentive to be honest and bidding one's true value dominates any lower bid. Our mechanism's efficiency is within a constant fractio...
Added values of photovoltaic power systems
Energy Technology Data Exchange (ETDEWEB)
NONE
2001-03-15
The structure, ownership and operation of electricity systems around the world are changing in response to industry restructuring, the availability of new technologies and increasing environmental awareness. At the same time, many countries have yet to provide basic energy services for their populations, particularly in areas not served by the electricity grid. Large-scale, central power generation and distribution which characterized the electricity industry for much of the 20{sup th} century is being challenged by new technologies, which are cleaner, faster to deploy and better matched to local requirements. Higher values are being placed on ancillary services, such as power system reliability and voltage stability, so that a simple comparison of energy cost is no longer appropriate as a measure of competitiveness. Solar photovoltaic electricity is unique amongst the new energy sources for the wide range of energy and non-energy benefits which can be provided, while the use of photovoltaic power systems as an integral part of a building provides the greatest opportunity for exploiting non-energy benefits and for adding value to the photovoltaic power system. This report documents the potential added values or non-energy benefits photovoltaic power systems can provide, the current state of market development and the key barriers faced by renewable energy technologies generally and photovoltaic power systems in particular. Means by which non-energy benefits may be used to overcome barriers to the use of photovoltaic power systems are then discussed, with specific attention to the use of building integrated photovoltaics. (author)
The AD: The unique anti-accelerator
Slide show by Maximilien Brice. Voice (French only): Jacques Fichet. Content: Paola Catapano, Django Manglunki, CERN Bulletin
2011-01-01
Unlike other machines whose performance is measured in terms of energy records, AD's uniqueness resides in the fact that it can very effectively decelerate beams. At the hearth of antimatter production at CERN, the AD is making headlines in the world's press. This provides an excellent opportunity for us to retrace its history in images. var flash_video_player=get_video_player_path(); insert_player_for_external('Video/Public/Movies/2011/CERN-MOVIE-2011-083/CERN-MOVIE-2011-083-0753-kbps-480x360-25-fps-audio-64-kbps-44-kHz-stereo', 'mms://mediastream.cern.ch/MediaArchive/Video/Public/Movies/2011/CERN-MOVIE-2011-083/CERN-MOVIE-2011-083-0480-kbps-384x288-25-fps-audio-128-kbps-48-kHz-stereo.wmv', 'false', 480, 360, 'http://mediaarchive.cern.ch/MediaArchive/Video/Public/Movies/2011/CERN-MOVIE-2011-083/CERN-MOVIE-2011-083-posterframe-480x360-at-5-percent.jpg', '1357551', true, '');
Adding momentum to supersymmetric geometries
Energy Technology Data Exchange (ETDEWEB)
Lunin, Oleg, E-mail: olunin@albany.edu [Department of Physics, University at Albany (SUNY), Albany, NY 12222 (United States); Mathur, Samir D., E-mail: mathur.16@osu.edu [Department of Physics, Ohio State University, Columbus, OH 43210 (United States); Turton, David, E-mail: turton.7@osu.edu [Department of Physics, Ohio State University, Columbus, OH 43210 (United States)
2013-03-11
We consider general supersymmetric solutions to minimal supergravity in six dimensions, trivially lifted to IIB supergravity. To any such solution we add a traveling wave deformation involving the additional directions. The deformed solution is given in terms of a function which is harmonic in the background geometry. We also present a family of explicit examples describing microstates of the D1-D5 system on T{sup 4}. In the case where the background contains a large AdS region, the deformation is identified as corresponding to an action of a U(1) current of the D1-D5 orbifold CFT on a given state.
Adding momentum to supersymmetric geometries
Lunin, Oleg; Turton, David
2012-01-01
We consider general supersymmetric solutions to minimal supergravity in six dimensions, trivially lifted to IIB supergravity. To any such solution we add a travelling-wave deformation involving the additional directions. The deformed solution is given in terms of a function which is harmonic in the background geometry. We also present a family of explicit examples describing microstates of the D1-D5 system on T^4. In the case where the background contains a large AdS region, the deformation is identified as corresponding to an action of a U(1) current of the D1-D5 orbifold CFT on a given state.
Energy Technology Data Exchange (ETDEWEB)
NONE
2006-11-07
will be willing to make investments themselves or to attract sufficient capital to keep up the necessary pace of investment. Upstream investment has been rising rapidly in the last few years, but much of the increase is due to surging costs. Expanding production in the lowest-cost countries - most of them in OPEC - will be central to meeting the world's oil needs at reasonable cost. The prospect of accelerating declines in production at individual oilfields is adding to these uncertainties. The findings of an unprecedented field-by-field analysis of the historical production trends of 800 oilfields indicate that decline rates are likely to rise significantly in the long term, from an average of 6.7% today to 8.6% in 2030. WEO-2008 also analyses policy options for tackling climate change after 2012, when a new global agreement - to be negotiated at the UN Conference of the Parties in Copenhagen next year - is due to take effect. This analysis assumes a hybrid policy approach, comprising a plausible combination of cap-and-trade systems, sectoral agreements and national measures. On current trends, energy-related CO2 emissions are set to increase by 45% between 2006 and 2030, reaching 41 Gt. Three-quarters of the increase arises in China, India and the Middle East, and 97% in non-OECD countries as a whole. Stabilising greenhouse gas concentration at 550 ppm of CO2-equivalent, which would limit the temperature increase to about 3 deg C, would require emissions to rise to no more than 33 Gt in 2030 and to fall in the longer term. The share of low-carbon energy - hydropower, nuclear, biomass, other renewables and fossil-fuel power plants equipped with carbon capture and storage (CCS) - in the world primary energy mix would need to expand from 19% in 2006 to 26% in 2030. This would call for $4.1 trillion more investment in energy-related infrastructure and equipment than in the Reference Scenario - equal to 0.2% of annual world GDP. Most of the increase is on the demand
Holographic properties in three-dimensional AdS soliton using $AdS_3/CFT_2$
Peng, Yan
2016-01-01
We study the holographic description of a superconductor by the $AdS_{3}/CFT_{2}$ correspondence. The system is constructed with a Maxwell field and a charged scalar field coupled in the (2+1)-dimensional AdS soliton background. With analytical methods, we obtain the exact expression for the critical chemical potential as $\\mu_{c} = 1 + \\sqrt{1+m^2}$, which has also been generalized to higher dimensions as $\\mu_c \\thickapprox a + \\sqrt{m^2-m_{BF}^2}$ in this work. Around the phase transition points, we find a correspondence between the value of the scalar field at the tip and the scalar operator at infinity. We also arrive at the classical second order phase transition threshold exponent $\\beta=\\frac{1}{2}$ as the same as the mean field theory near the critical chemical potential. As the condensation becomes heavier, we show surprisingly that superconducting phases exist only in a certain range of the chemical potential, which is very different from higher-dimensional cases. And for the small enough negative ...
DEFF Research Database (Denmark)
Schröder, Philipp J.H.; Sørensen, Allan
2010-01-01
a general equilibrium monopolistic competition model with heterogeneous firms and intra-industry reallocations. We show that the welfare superiority of ad valorem over unit taxes under imperfect competition is not only preserved but amplified. The additional difference between the tools arises because unit...
The activities of HPPA technology related to ADS in China
Guan Xia Ling; Ding Da Zhao; Fang Jia Xun; Fang Shou Xian; Fu Shin Ian; Guo, Z Y; Jiang Wei; Li Jie Quan; Luo Zi Hua; Ouyang Hua Fu; Peng Chao Hua; Xu Tao Guang; Xu Wen Wu; Yu Qi; Zhang Zong Hua; Zhao Sheng Chu
2001-01-01
High Power Proton Accelerator (HPPA) is being studied all over world for numerous applications, which includes the waste transmutation, spallation neutron source and material irradiation facilities. In China, a multi-purpose verification system as a first phase of Chinese ADS program consists of a low energy accelerator (150 MeV/3 mA proton linac) and a swimming pool light water sub-critical reactor. The activities of HPPA technology related to ADS in China, which includes the intense proton ECR source, the RFQ accelerator and some other technology of HPPA, are described
de Boer, J.; Hubeny, V.E.; Rangamani, M.; Shigemori, M.
2009-01-01
We study Brownian motion and the associated Langevin equation in AdS/CFT. The Brownian particle is realized in the bulk spacetime as a probe fundamental string in an asymptotically AdS black hole background, stretching between the AdS boundary and the horizon. The modes on the string are excited by
An Investigation of AdS2 Backreaction and Holography
Engelsöy, Julius; Verlinde, Herman
2016-01-01
We investigate a dilaton gravity model in AdS2 proposed by Almheiri and Polchinski and develop an 1D effective description in terms of a dynamical boundary time with a Schwarzian derivative action. We show that the effective model is equivalent to a 1D version of Liouville theory, and investigate its dynamics and symmetries via a standard canonical framework. We include the coupling to arbitrary conformal matter and analyze the effective action in the presence of possible sources. We compute commutators of local operators at large time separation, and match the result with the time shift due to a gravitational shockwave interaction. We study a black hole evaporation process and comment on the role of entropy in this model.
Supersymmetry Properties of AdS Supergravity Backgrounds
Beck, Samuel; Gutowski, Jan; Papadopoulos, George
2017-01-01
Anti-de Sitter supergravity backgrounds are of particular interest in light of the AdS/CFT correspondence, which relates them to dual conformal field theories on the boundary of the anti-de Sitter space. We have investigated the forms of the supersymmetries these backgrounds preserve by solving the Killing spinor equations on the anti-de Sitter components of these spaces. We have found that a supersymmetric AdSn background necessarily preserves 2⌊n/2⌋ k supersymmetries for n 0 . Additionally, we have found that the Killing spinors of each background are exactly the zeroes of a Dirac-like operator constructed from the Killing spinor equations.
Jet physics from static charges in AdS space
Chien, Yang-Ting; Schwartz, Matthew D.; Simmons-Duffin, David; Stewart, Iain W.
2012-02-01
Soft interactions with high-energy jets are explored in radial coordinates which exploit the approximately conformal behavior of perturbative gauge theories. In these coordinates, the jets, approximated by Wilson lines, become static charges in Euclidean AdS. The anomalous dimension of the corresponding Wilson line operator is then determined by the potential energy of the charges. To study these Wilson lines we introduce a “conformal gauge” which does not have kinetic mixing between radial and angular directions, and show that a number of properties of Wilson lines are reproduced through relatively simple calculations. For example, certain nonplanar graphs involving multiple Wilson lines automatically vanish. We also discuss the linear growth of the charges’ imaginary potential energy with separation, and a relationship between Wilson line diagrams and Witten diagrams.
Jet Physics from Static Charges in AdS
Chien, Yang-Ting; Simmons-Duffin, David; Stewart, Iain W
2011-01-01
Soft interactions with high-energy jets are explored in radial coordinates which exploit the approximately conformal behavior of perturbative gauge theories. In these coordinates, the jets, approximated by Wilson lines, become static charges in Euclidean AdS. The anomalous dimension of the corresponding Wilson line operator is then determined by the potential energy of the charges. To study these Wilson lines we introduce a "conformal gauge" which does not have kinetic mixing between radial and angular directions, and show that a number of properties of Wilson lines are reproduced through relatively simple calculations. For example, certain non-planar graphs involving multiple Wilson lines automatically vanish. We also discuss the linear growth of the charges' imaginary potential energy with separation, and a relationship between Wilson line diagrams and Witten diagrams.
Bootstrapping Pure Quantum Gravity in AdS3
Bae, Jin-Beom; Lee, Sungjay
2016-01-01
The three-dimensional pure quantum gravity with negative cosmological constant is supposed to be dual to the extremal conformal field theory of central charge $c=24k$ in two dimensions. We employ the conformal bootstrap method to analyze the extremal CFTs, and find numerical evidence for the non-existence of the extremal CFTs for sufficiently large central charge ($k \\ge 20$). We also explore near-extremal CFTs, a small modification of extremal ones, and find similar evidence for their non-existence for large central charge. This indicates, under the assumption of holomorphic factorization, the pure gravity in the weakly curved AdS$_3$ do not exist as a consistent quantum theory.
Thermodynamics of charged Lovelock: AdS black holes
Energy Technology Data Exchange (ETDEWEB)
Prasobh, C.B.; Suresh, Jishnu; Kuriakose, V.C. [Cochin University of Science and Technology, Department of Physics, Cochin (India)
2016-04-15
We investigate the thermodynamic behavior of maximally symmetric charged, asymptotically AdS black hole solutions of Lovelock gravity. We explore the thermodynamic stability of such solutions by the ordinary method of calculating the specific heat of the black holes and investigating its divergences which signal second-order phase transitions between black hole states. We then utilize the methods of thermodynamic geometry of black hole spacetimes in order to explain the origin of these points of divergence. We calculate the curvature scalar corresponding to a Legendre-invariant thermodynamic metric of these spacetimes and find that the divergences in the black hole specific heat correspond to singularities in the thermodynamic phase space. We also calculate the area spectrum for large black holes in the model by applying the Bohr-Sommerfeld quantization to the adiabatic invariant calculated for the spacetime. (orig.)
On Information Loss in AdS$_3$/CFT$_2$
Fitzpatrick, A Liam; Li, Daliang; Wang, Junpu
2016-01-01
We discuss information loss from black hole physics in AdS$_3$, focusing on two sharp signatures infecting CFT$_2$ correlators at large central charge $c$: 'forbidden singularities' arising from Euclidean-time periodicity due to the effective Hawking temperature, and late-time exponential decay in the Lorentzian region. We study an infinite class of examples where forbidden singularities can be resolved by non-perturbative effects at finite $c$, and we show that the resolution has certain universal features that also apply in the general case. Analytically continuing to the Lorentzian regime, we find that the non-perturbative effects that resolve forbidden singularities qualitatively change the behavior of correlators at times $t \\sim S_{BH}$, the black hole entropy. This may resolve the exponential decay of correlators at late times in black hole backgrounds. By Borel resumming the $1/c$ expansion of exact examples, we explicitly identify 'information-restoring' effects from heavy states that should correspo...
Thermodynamics of charged Lovelock: AdS black holes
Prasobh, C. B.; Suresh, Jishnu; Kuriakose, V. C.
2016-04-01
We investigate the thermodynamic behavior of maximally symmetric charged, asymptotically AdS black hole solutions of Lovelock gravity. We explore the thermodynamic stability of such solutions by the ordinary method of calculating the specific heat of the black holes and investigating its divergences which signal second-order phase transitions between black hole states. We then utilize the methods of thermodynamic geometry of black hole spacetimes in order to explain the origin of these points of divergence. We calculate the curvature scalar corresponding to a Legendre-invariant thermodynamic metric of these spacetimes and find that the divergences in the black hole specific heat correspond to singularities in the thermodynamic phase space. We also calculate the area spectrum for large black holes in the model by applying the Bohr-Sommerfeld quantization to the adiabatic invariant calculated for the spacetime.
Finite-size effect of \\eta-deformed AdS_5 x S^5 at strong coupling
Ahn, Changrim
2016-01-01
We compute Luscher corrections for a giant magnon in the \\eta-deformed (AdS_5\\times S^5)_{\\eta} using the su(2|2)_q-invariant S-matrix at strong coupling and compare with the finite-size effect of the corresponding string state, derived previously. We find that these two results match and confirm that the su(2|2)_q-invariant S-matrix is describing world-sheet excitations of the \\eta-deformed background.
Bound States of the q-Deformed AdS5 x S5 Superstring S-matrix
Hoare, Ben; Miramontes, J Luis
2012-01-01
The investigation of the q deformation of the S-matrix for excitations on the string world sheet in AdS5 x S5 is continued. We argue that due to the lack of Lorentz invariance the situation is more subtle than in a relativistic theory in that the nature of bound states depends on their momentum. At low enough momentum |p|1. This subtlety fixes a problem involving the consistency of crossing symmetry with the relativistic limit found in earlier work. With mirror kinematics, obtained after a double Wick rotation, the bound state structure is simpler and there are no marginally unstable bound states.
A local-world evolving hypernetwork model
Yang, Guang-Yong; Liu, Jian-Guo
2014-01-01
Complex hypernetworks are ubiquitous in the real system. It is very important to investigate the evolution mechanisms. In this paper, we present a local-world evolving hypernetwork model by taking into account the hyperedge growth and local-world hyperedge preferential attachment mechanisms. At each time step, a newly added hyperedge encircles a new coming node and a number of nodes from a randomly selected local world. The number of the selected nodes from the local world obeys the uniform distribution and its mean value is m. The analytical and simulation results show that the hyperdegree approximately obeys the power-law form and the exponent of hyperdegree distribution is γ = 2 + 1/m. Furthermore, we numerically investigate the node degree, hyperedge degree, clustering coefficient, as well as the average distance, and find that the hypernetwork model shares the scale-free and small-world properties, which shed some light for deeply understanding the evolution mechanism of the real systems.
Facilities Management and Added Value
DEFF Research Database (Denmark)
Jensen, Per Anker
2010-01-01
Aim: This paper aims to present different models of the concept of the added value of Facilities Management (FM), including the FM Value Map, which forms the basis of research group in EuroFM, and to present some of the results of this research collaboration. Approach and methodology: The paper...... on the aimed output) and the internal resource based view (with a focus on the input from FM and RE). Good relationship management and building on trust shows to be equally important as delivering the agreed services. In order to measure the multi-dimensional components of adding value both qualitative...... is based on literature reviews of the most influential journals within the academic fields of FM, Corporate Real Estate Management and Business to Business Marketing and discussions between participants of the research group working on a further exploration and testing of the FM Value Map. Conclusions...
DEFF Research Database (Denmark)
Antila, Kari; Lötjönen, Jyrki; Thurfjell, Lennart;
2013-01-01
can be managed. Today the significance of early and precise diagnosis of AD is emphasized in order to minimize its irreversible effects on the nervous system. When new drugs and therapies enter the market it is also vital to effectively identify the right candidates to benefit from these. The main...... candidates and implement the framework in software. The results are currently used in several research projects, licensed to commercial use and being tested for clinical use in several trials....
2013-03-25
... Preparations for the International Telecommunication Union World Telecommunication Development Conference (ITU... Telecommunication Advisory Committee (ITAC) to review the activities of its ad hoc group for preparations for the ITU World Telecommunication Development Conference (WTDC 2014), as well as preparations for...
Energy Technology Data Exchange (ETDEWEB)
Fitzpatrick, A.Liam; /Boston U.; Kaplan, Jared; /SLAC
2012-02-14
We show that suitably regulated multi-trace primary states in large N CFTs behave like 'in' and 'out' scattering states in the flat-space limit of AdS. Their transition matrix elements approach the exact scattering amplitudes for the bulk theory, providing a natural CFT definition of the flat space S-Matrix. We study corrections resulting from the AdS curvature and particle propagation far from the center of AdS, and show that AdS simply provides an IR regulator that disappears in the flat space limit.
ADS Labs - Supporting Information Discovery in Science Education
Henneken, Edwin A
2012-01-01
The SAO/NASA Astrophysics Data System (ADS) is an open access digital library portal for researchers in astronomy and physics, operated by the Smithsonian Astrophysical Observatory (SAO) under a NASA grant, successfully serving the professional science community for two decades. Currently there are about 55,000 frequent users (100+ queries per year), and up to 10 million infrequent users per year. Access by the general public now accounts for about half of all ADS use, demonstrating the vast reach of the content in our databases. The visibility and use of content in the ADS can be measured by the fact that there are over 17,000 links from Wikipedia pages to ADS content, a figure comparable to the number of links that Wikipedia has to OCLCs WorldCat catalog. The ADS, through its holdings and innovative techniques available in ADS Labs (http://adslabs.org), offers an environment for information discovery that is unlike any other service currently available to the astrophysics community. Literature discovery and...
Towards More Realistic Mobility Model in Vehicular Ad Hoc Network
Dhananjay S. Gaikwad; Mahesh Lagad; Prashant Suryawanshi; Vaibhav Maske
2012-01-01
Mobility models or the movement patterns of nodes communicating wirelessely, play a vital role in the simulation-based evaluation of vehicular Ad Hoc Networks (VANETs). Even though recent research has developed models that better corresponds to real world mobility, we still have a limited understanding of the level of the required level of mobility details for modeling and simulating VANETs. In this paper, we propose a new mobility model for VANETs that works on the city area and map the topo...
Towards Timelike Singularity via AdS Dual
Bhowmick, Samrat
2016-01-01
It is well known that Kasner geometry with spacelike singularity can be extended to bulk AdS-like geometry, furthermore one can study field theory on this Kasner space via its gravity dual. In this paper, we show that there exists a Kasner-like geometry with timelike singularity for which one can construct a dual gravity description. We then study various minimal surfaces including spacelike geodesics. Finally, we compute correlators of highly massive operators in the boundary field theory with a geodesic approximation.
Holography in 3D AdS gravity with torsion
Blagojević, Milutin; Miskovic, Olivera; Olea, Rodrigo
2013-01-01
Basic aspects of the AdS/CFT correspondence are studied in the framework of 3-dimensional gravity with torsion. After choosing a consistent holographic ansatz, we formulate an improved approach to the Noether--Ward identities for the boundary theory. The method is applied first to the topological Mielke--Baekler model, and then to the more interesting (parity-preserving) 3-dimensional gravity with propagating torsion. In both cases, we find the finite holographic energy-momentum and spin currents and obtain the associated (anomalous) Noether--Ward identities.
Canonical energy and hairy AdS black holes
Hyun, Seungjoon; Yi, Sang-Heon
2016-01-01
We propose the modified version of the canonical energy which was introduced originally by Hollands and Wald. Our construction depends only on the Euler-Lagrange expression of the system and thus is independent of the ambiguity in the Lagrangian. After some comments on our construction, we briefly mention on the relevance of our construction to the boundary information metric in the context of the AdS/CFT correspondence. We also study the stability of three-dimensional hairy extremal black holes by using our construction.
Shanghai Highlight: World Expo
Institute of Scientific and Technical Information of China (English)
Guo Yan
2009-01-01
@@ The proposals regarding the Shanghai Expo attracted the World Expo committee great concern. During the two sessions, the Shanghai World Expo organizer promised that they will play more active role in holding the expo. Though the world is suffering the global crisis, the organizer be-lieved that this is a rare opportunity and as the World Expo 2010 to be held in Shanghai could help China overcome economic dif-ficulties and lift the world out of the crisis shadow.
Hamiltonian of Green—Schwarz IIB Superstring Theory in AdS3 × S3 Background
Institute of Scientific and Technical Information of China (English)
KE San-Min; WANG Chun; WANG Zhan-Yun; JIANG Ke-Xia; SHI Kang-Jie
2011-01-01
We parameterize the Green-Schwarz IIB superstring in the AdS3 × S3 background under the light cone gauge by the method of Metsaev and Tseytlin in AdS3 and by the method of Rahmfeld and Rajaraman in S3.After some calculation,we obtain the corresponding Maurer-Cartan 1-forms and the action.Then we fix two bosonic variables x+ =τ and y5 ＝ σ,perform the partial Legendre transformation of the remaining bosonic variables,and find a Lagrangian that is linear in velocity after eliminating the metric of the world sheet.We also give the Hamiltonian and prove that the system is local and the Poisson bracket of the theory can be well defined.Using these results,one can further study the properties of solution space,solution transformation and the structure of theflat current algebra of the superstring in the AdS3 × S3 background.
On modular properties of the AdS3 CFT
Baron, Walter
2010-01-01
We study modular properties of the AdS3 WZNW model. Although the Euclidean partition function is modular invariant, the characters on the Euclidean torus are ill-defined and their modular transformations are unknown. We reconsider the characters defined on the Lorentzian torus, focusing on their structure as distributions. We find a generalized S matrix, depending on the sign of the real modular parameters, which has two diagonal blocks and one off-diagonal block, mixing discrete and continuous representations, that we fully determine. We then explore the relations among the modular transformations, the fusion algebra and the boundary states. We explicitly construct Ishibashi states for the maximally symmetric D-branes and show that the generalized S matrix defines the one-point functions associated to point-like and H2 branes as well as the fusion rules of the degenerate representations of SL(2,R) appearing in the open string spectrum of the point-like D-branes, through a generalized Verlinde theorem.
Teaching World Religions without Teaching "World Religions"
Locklin, Reid B.; Tiemeier, Tracy; Vento, Johann M.
2012-01-01
Tomoko Masuzawa and a number of other contemporary scholars have recently problematized the categories of "religion" and "world religions" and, in some cases, called for its abandonment altogether as a discipline of scholarly study. In this collaborative essay, we respond to this critique by highlighting three attempts to teach world religions…
ADS Labs: Supporting Information Discovery in Science Education
Henneken, E. A.
2013-04-01
The SAO/NASA Astrophysics Data System (ADS) is an open access digital library portal for researchers in astronomy and physics, operated by the Smithsonian Astrophysical Observatory (SAO) under a NASA grant, successfully serving the professional science community for two decades. Currently there are about 55,000 frequent users (100+ queries per year), and up to 10 million infrequent users per year. Access by the general public now accounts for about half of all ADS use, demonstrating the vast reach of the content in our databases. The visibility and use of content in the ADS can be measured by the fact that there are over 17,000 links from Wikipedia pages to ADS content, a figure comparable to the number of links that Wikipedia has to OCLC's WorldCat catalog. The ADS, through its holdings and innovative techniques available in ADS Labs, offers an environment for information discovery that is unlike any other service currently available to the astrophysics community. Literature discovery and review are important components of science education, aiding the process of preparing for a class, project, or presentation. The ADS has been recognized as a rich source of information for the science education community in astronomy, thanks to its collaborations within the astronomy community, publishers and projects like ComPADRE. One element that makes the ADS uniquely relevant for the science education community is the availability of powerful tools to explore aspects of the astronomy literature as well as the relationship between topics, people, observations and scientific papers. The other element is the extensive repository of scanned literature, a significant fraction of which consists of historical literature.
Energy Technology Data Exchange (ETDEWEB)
NONE
2006-11-07
will be willing to make investments themselves or to attract sufficient capital to keep up the necessary pace of investment. Upstream investment has been rising rapidly in the last few years, but much of the increase is due to surging costs. Expanding production in the lowest-cost countries - most of them in OPEC - will be central to meeting the world's oil needs at reasonable cost. The prospect of accelerating declines in production at individual oilfields is adding to these uncertainties. The findings of an unprecedented field-by-field analysis of the historical production trends of 800 oilfields indicate that decline rates are likely to rise significantly in the long term, from an average of 6.7% today to 8.6% in 2030. WEO-2008 also analyses policy options for tackling climate change after 2012, when a new global agreement - to be negotiated at the UN Conference of the Parties in Copenhagen next year - is due to take effect. This analysis assumes a hybrid policy approach, comprising a plausible combination of cap-and-trade systems, sectoral agreements and national measures. On current trends, energy-related CO2 emissions are set to increase by 45% between 2006 and 2030, reaching 41 Gt. Three-quarters of the increase arises in China, India and the Middle East, and 97% in non-OECD countries as a whole. Stabilising greenhouse gas concentration at 550 ppm of CO2-equivalent, which would limit the temperature increase to about 3 deg C, would require emissions to rise to no more than 33 Gt in 2030 and to fall in the longer term. The share of low-carbon energy - hydropower, nuclear, biomass, other renewables and fossil-fuel power plants equipped with carbon capture and storage (CCS) - in the world primary energy mix would need to expand from 19% in 2006 to 26% in 2030. This would call for $4.1 trillion more investment in energy-related infrastructure and equipment than in the Reference Scenario - equal to 0.2% of annual world GDP. Most of the increase is on the demand
Entanglement Entropy of AdS Black Holes
Directory of Open Access Journals (Sweden)
Maurizio Melis
2010-11-01
Full Text Available We review recent progress in understanding the entanglement entropy of gravitational configurations for anti-de Sitter gravity in two and three spacetime dimensions using the AdS/CFT correspondence. We derive simple expressions for the entanglement entropy of two- and three-dimensional black holes. In both cases, the leading term of the entanglement entropy in the large black hole mass expansion reproduces exactly the Bekenstein-Hawking entropy, whereas the subleading term behaves logarithmically. In particular, for the BTZ black hole the leading term of the entanglement entropy can be obtained from the large temperature expansion of the partition function of a broad class of 2D CFTs on the torus.
An Integrable Deformation of the AdS5 x S5 Superstring
Hollowood, Timothy J; Schmidtt, David
2014-01-01
The S-matrix on the world-sheet theory of the string in AdS5 x S5 has previously been shown to admit a deformation where the symmetry algebra is replaced by the associated quantum group. The case where q is real has been identified as a particular deformation of the Green-Schwarz sigma model. An interpretation of the case with q a root of unity has, until now, been lacking. We show that the Green-Schwarz sigma model admits a discrete deformation which can be viewed as a rather simple deformation of the F/F gauged WZW model, where F=PSU(2,2|4). The deformation parameter q is then a k-th root of unity where k is the level. The deformed theory has the same equations-of-motion as the Green-Schwarz sigma model but has a different symplectic structure. We show that the resulting theory is integrable and has just the right amount of kappa-symmetries that appear as a remnant of the fermionic part of the original gauge symmetry. This points to the existence of a fully consistent deformed string background.
Puzzles of η-deformed AdS5 × S5
Arutyunov, Gleb; Borsato, Riccardo; Frolov, Sergey
2015-12-01
We derive the part of the Lagrangian for the sigma model on the η-deformed AdS5 × S5 space which is quadratic in fermions and has the full dependence on bosons. We then show that there exists a field redefinition which brings the corresponding La-grangian to the standard form of type IIB Green-Schwarz superstring. Reading off the corresponding RR couplings, we observe that they fail to satisfy the supergravity equations of motion, despite the presence of κ-symmetry. However, in a special scaling limit our solution reproduces the supergravity background found by Maldacena and Russo. Further, using the fermionic Lagrangian, we compute a number of new matrix elements of the tree level world-sheet scattering matrix. We then show that after a unitary transformation on the basis of two-particle states which is not one-particle factorisable, the corresponding T-matrix factorises into two equivalent parts. Each part satisfies the classical Yang-Baxter equation and coincides with the large tension limit of the q-deformed S-matrix.
Puzzles of eta-deformed AdS_5 x S^5
Arutyunov, Gleb; Frolov, Sergey
2015-01-01
We derive the part of the Lagrangian for the sigma model on the eta-deformed AdS_5 x S^5 space which is quadratic in fermions and has the full dependence on bosons. We then show that there exists a field redefinition which brings the corresponding Lagrangian to the standard form of type IIB Green-Schwarz superstring. Reading off the corresponding RR couplings, we observe that they fail to satisfy the supergravity equations of motion, despite the presence of kappa-symmetry. However, in a special scaling limit our solution reproduces the supergravity background found by Maldacena and Russo. Further, using the fermionic Lagrangian, we compute a number of new matrix elements of the tree level world-sheet scattering matrix. We then show that after a unitary transformation on the basis of two-particle states which is not one-particle factorisable, the corresponding T-matrix factorises into two equivalent parts. Each part satisfies the classical Yang-Baxter equation and coincides with the large tension limit of the ...
MUSICAL ARRANGEMENT OF MEDIA ADS
Directory of Open Access Journals (Sweden)
Chernyshov Alexander V.
2015-01-01
Full Text Available The music-compositional principles of commercial and political advertising and also the self-promotion of electronic media (radio, television, Internet are considered in this mediatext: from the elementary beeps, symbolic functions, emblems/logos and musical brands to the sound engineering technology to underscore the product's name and the complex synthesis between music and intra movements and color-light design of frames. Simultaneously examines, how the musical arrangement of ethereal advertising is involved in creation the emotional drama or bravado which reach the level of explicit or associative counterpoint 'music with the advertised object or subject' and which extend to expression of cultural image of all the broadcast channel. The article explores the works of the next genres like infomercial, teleshopping, film-ad, and autonomous commercials that have been produced in European countries or USA.
Axenides, Minos; Linardopoulos, Georgios
2013-01-01
We study membrane configurations in AdS_{7/4}xS^{4/7}. The membranes are wrapped around the compact manifold S^{4/7} and are dynamically equivalent to bosonic strings in AdS_5. We thus conveniently identify them as "stringy membranes". For the case of AdS_7xS^4, their construction is carried out by embedding the Polyakov action for classical bosonic strings in AdS_5, into the corresponding membrane action. Therefore, every string configuration in AdS_5 can be realized by an appropriately chosen stringy membrane in AdS_7xS^4. We discuss the possibility of this being also the case for stringy membranes in AdS_4xS^7/Z^k (k > 1 or k = 1). By performing a stability analysis to the constructed solutions, we find that the (membrane) fluctuations along their transverse directions are organized in multiple Lam\\'{e} stability bands and gaps in the space of parameters of the configurations. In this membrane picture, strings exhibit a single band/gap structure. Since the spectrum of quadratic fluctuations is important fo...
RFID added value sensing capabilities
DEFF Research Database (Denmark)
Anggorjati, B.; Çetin, K.; Mihovska, A.
2010-01-01
Radio frequency identification (RFID) is a key technology for Europe. Since the initial emergence of the technology, there has been a noticeable shift away from RFID pilot projects of the early days, towards a broad deployment of RFID in order to increase the efficiency and innovation of processes....... Even though Europe is a leading player in the world of RFID technology, several challenges need to be addressed in order for RFID to reach its full potential. The funded under FP7 ICT project ASPIRE is one of the coordinated European efforts to further the advancement of this technology, in the areas...... of enabling technology development for RFID. In particular, the focus of ASPIRE is on design, development and adoption of an innovative, programmable, royalty-free, lightweight and privacy friendly RFID middleware....
Penedones, Joao
2016-01-01
We introduce the AdS/CFT correspondence as a natural extension of QFT in a fixed AdS background. We start by reviewing some general concepts of CFT, including the embedding space formalism. We then consider QFT in a fixed AdS background and show that one can define boundary operators that enjoy very similar properties as in a CFT, except for the lack of a stress tensor. Including a dynamical metric in AdS generates a boundary stress tensor and completes the CFT axioms. We also discuss some applications of the bulk geometric intuition to strongly coupled QFT. Finally, we end with a review of the main properties of Mellin amplitudes for CFT correlation functions and their uses in the context of AdS/CFT.
Recurring Anomaly Detection System (ReADS)
National Aeronautics and Space Administration — Overview: ReADS can analyze text reports, such as aviation reports and problem or maintenance records. ReADS uses text clustering algorithms to group loosely related...
The AdS/CFT/Unparticle Correspondence
Cacciapaglia, Giacomo; Terning, John
2009-01-01
We examine the correspondence between the anti-de Sitter (AdS) description of conformal field theories (CFTs) and the unparticle description of CFTs. We show how unparticle actions are equivalent to holographic boundary actions for fields in AdS, and how massive unparticles provide a new type of infrared cutoff that can be simply implemented in AdS by a soft breaking of conformal symmetry. We also show that processes involving scalar unparticles with dimensions d_s<2 or fermion unparticles with dimensions d_f<5/2 are insensitive to ultraviolet cutoff effects. Finally we show that gauge interactions for unparticles can be described by bulk gauge interactions in AdS and that they correspond to minimal gauging of the non-local effective action, and we compute the fermion unparticle production cross-section.
TV Snack Ads Make Preschoolers Snack More
... Sesame Street" interrupted by TV ads for a salty snack food ended up eating more of that ... watched the show with commercials for a popular salty snack. The ads depicted kids happily playing and ...
Directory of Open Access Journals (Sweden)
Manasvi Kalra,
2016-02-01
Full Text Available The apps consist of advertisements to promote their products. Not all of them are appropriate to resume. Therefore various algorithms have been used in order to block those apps from existence but none of them is completely successful. In our app we are using an antivirus which can by default block those spy apps and remove them from the web page. The algorithm which has been used makes use of various ant viruses in the background which detect irrelevant and intimate apps and then our algorithm will demolish them. Certain apps are non-trustworthy where one click can spy all the mobile data. They block those apps and works on security. We are working on secure ads for mobile apps. It can also work as a basic antivirus where it detects the viruses like malwares in any of your installed apps or downloads. It will create a popup of discarding or keeping it. Mobile applications can be downloaded from anywhere like amazon, googleplay, apps store etc. There is no rigorous verification of an application when it is uploaded to the market. One can easily develop a malicious application and upload it to the app market. The user itself is responsible for accepting the risk of an app available from secondary markets. Therefore, we have decided to develop this app to make the market more secure and bounded. In future, It will take the mobile market while consuming minimal additional resources and preserving user privacy.
Material Developing for ADS Beam Window
Institute of Scientific and Technical Information of China (English)
XUYong-li; XUYuan-chao; LIHua-qing; NINGGuang-sheng; WANFa-rong; ZHAOFei
2003-01-01
The irradiation damage and the chemical interaction with the coolant for the ADS target and the structure materials are the key issues in ADS engineering. The developing of the materials that are irradiation and corrosion resistance is the important topic in ADS program in many countries. In this case,a topic of the material developing for the beam window has been proposed in our ADS program.
16 CFR 460.18 - Insulation ads.
2010-01-01
... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Insulation ads. 460.18 Section 460.18 Commercial Practices FEDERAL TRADE COMMISSION TRADE REGULATION RULES LABELING AND ADVERTISING OF HOME INSULATION § 460.18 Insulation ads. (a) If your ad gives an R-value, you must give the type of insulation...
Automated Experiments on Ad Privacy Settings
Directory of Open Access Journals (Sweden)
Datta Amit
2015-04-01
Full Text Available To partly address people’s concerns over web tracking, Google has created the Ad Settings webpage to provide information about and some choice over the profiles Google creates on users. We present AdFisher, an automated tool that explores how user behaviors, Google’s ads, and Ad Settings interact. AdFisher can run browser-based experiments and analyze data using machine learning and significance tests. Our tool uses a rigorous experimental design and statistical analysis to ensure the statistical soundness of our results. We use AdFisher to find that the Ad Settings was opaque about some features of a user’s profile, that it does provide some choice on ads, and that these choices can lead to seemingly discriminatory ads. In particular, we found that visiting webpages associated with substance abuse changed the ads shown but not the settings page. We also found that setting the gender to female resulted in getting fewer instances of an ad related to high paying jobs than setting it to male. We cannot determine who caused these findings due to our limited visibility into the ad ecosystem, which includes Google, advertisers, websites, and users. Nevertheless, these results can form the starting point for deeper investigations by either the companies themselves or by regulatory bodies.
Supergravity on $AdS_{5/4} \\times$ Hopf Fibrations and Conformal Field Theories
1998-01-01
We obtain three and four dimensional conformal field theories with less than maximal supersymmetry by using their supergravity duals. These supergravity theories are type II on $AdS_5 \\times CP^2$, IIA on $AdS_4 \\times CP^3$, IIB on $AdS_5 \\times S^5/Z_k$ and D=11 supergravity on $AdS_4 \\times S^7/Z_k$. They are obtained from the spherically compactified ten and eleven dimensional theories by either Hopf reduction or by winding the U(1) fiber over the base.
Entropy, String Theory, and our World
Gregori, Andrea
2002-01-01
We investigate the consequences of two assumptions for String (or M) Theory, namely that: 1) all coordinates are compact and bound by the horizon of observation, 2) the ``dynamics'' of compactification is determined by the ``second law of thermodynamics'', i.e. the principle of entropy. We discuss how this leads to a phenomenologically consistent scenario for our world, both at the elementary particle's and at the cosmological level, without any fine tuning or further ``ad hoc'' constraint.
Waste valorization by biotechnological conversion into added value products.
Liguori, Rossana; Amore, Antonella; Faraco, Vincenza
2013-07-01
Fossil fuel reserves depletion, global warming, unrelenting population growth, and costly and problematic waste recycling call for renewable resources of energy and consumer products. As an alternative to the 100 % oil economy, production processes based on biomass can be developed. Huge amounts of lignocellulosic wastes are yearly produced all around the world. They include agricultural residues, food farming wastes, "green-grocer's wastes," tree pruning residues, and organic and paper fraction of urban solid wastes. The common ways currently adopted for disposal of these wastes present environmental and economic disadvantages. As an alternative, processes for adding value to wastes producing high added products should be developed, that is the upgrading concept: adding value to wastes by production of a product with desired reproducible properties, having economic and ecological advantages. A wide range of high added value products, such as enzymes, biofuels, organic acids, biopolymers, bioelectricity, and molecules for food and pharmaceutical industries, can be obtained by upgrading solid wastes. The most recent advancements of their production by biotechnological processes are overviewed in this manuscript.
Teaching World Religions without Teaching "World Religions"
Locklin, Reid B.; Tiemeier, Tracy; Vento, Johann M.
2012-01-01
Tomoko Masuzawa and a number of other contemporary scholars have recently problematized the categories of "religion" and "world religions" and, in some cases, called for its abandonment altogether as a discipline of scholarly study. In this collaborative essay, we respond to this critique by highlighting three attempts to teach…
My World Indoors: My Health My World.
Tharp, Barbara; Dresden, Judith; Denk, James; Moreno, Nancy
This curriculum guide for students in grades K-4 is part of the My Health My World series which explores environmental health issues. Focusing on indoor environmental health, it includes (1) an activities guide for teachers which focuses on physical science, life science, and the environment and health, presenting activity based lessons that…
BCR Routing for Intermittently Connected Mobile Ad hoc Networks
Directory of Open Access Journals (Sweden)
S. RAMESH
2014-03-01
Full Text Available The Wireless and the Mobile Networks appear to provide a wide range of applications. Following these, the Mobile Ad hoc Networks (MANET aid in wide development of many applications. The achievement of the real world applications are attained through effective routing. The Intermittently Connected Mobile Ad hoc Network (ICMANET is a sparse network where a full connectivity is never possible. ICMANET is a disconnected MANET and is also a Delay Tolerant Network (DTN that sustains for higher delays. The routing in a disseminated network is a difficult task. A new routing scheme called Bee Colony Routing (BCR is been proposed with a motto of achieving optimal result in delivering the data packet towards the destined node. BCR is proposed with the basis of Bee Colony Optimization technique (BCO. The routing in ICMNAET is done by means of Bee routing protocol. This paper enchants a novel routing methodology for data transmission in ICMANET.
Institute of Scientific and Technical Information of China (English)
无
2005-01-01
@@ The World Health Organization (WHO) collects and summarizes a wide range of quantitative data from a variety of health domains through country offices, regional offices and headquarter departments.
Protein domain organisation: adding order
Directory of Open Access Journals (Sweden)
Kummerfeld Sarah K
2009-01-01
Full Text Available Abstract Background Domains are the building blocks of proteins. During evolution, they have been duplicated, fused and recombined, to produce proteins with novel structures and functions. Structural and genome-scale studies have shown that pairs or groups of domains observed together in a protein are almost always found in only one N to C terminal order and are the result of a single recombination event that has been propagated by duplication of the multi-domain unit. Previous studies of domain organisation have used graph theory to represent the co-occurrence of domains within proteins. We build on this approach by adding directionality to the graphs and connecting nodes based on their relative order in the protein. Most of the time, the linear order of domains is conserved. However, using the directed graph representation we have identified non-linear features of domain organization that are over-represented in genomes. Recognising these patterns and unravelling how they have arisen may allow us to understand the functional relationships between domains and understand how the protein repertoire has evolved. Results We identify groups of domains that are not linearly conserved, but instead have been shuffled during evolution so that they occur in multiple different orders. We consider 192 genomes across all three kingdoms of life and use domain and protein annotation to understand their functional significance. To identify these features and assess their statistical significance, we represent the linear order of domains in proteins as a directed graph and apply graph theoretical methods. We describe two higher-order patterns of domain organisation: clusters and bi-directionally associated domain pairs and explore their functional importance and phylogenetic conservation. Conclusion Taking into account the order of domains, we have derived a novel picture of global protein organization. We found that all genomes have a higher than expected
Curating the CIA World Factbook
Directory of Open Access Journals (Sweden)
Peter Buneman
2009-12-01
Full Text Available The CIA World Factbook is a prime example of a curated database – a database that is constructed and maintained with a great deal of human effort in collecting, verifying, and annotating data. Preservation of old versions of the Factbook is important for verification of citations; it is also essential for anyone interested in the history of the data such as demographic change. Although the Factbook has been published, both physically and electronically, only for the past 30 years, we appear in danger of losing this history. This paper investigates the issues involved in capturing the history of an evolving database and its application to the CIA World Factbook. In particular it shows that there is substantial added value to be gained by preserving databases in such a way that questions about the change in data, (longitudinal queries can be readily answered. Within this paper, we describe techniques for recording change in a curated database and we describe novel techniques for querying the change. Using the example of this archived curated database, we discuss the extent to which the accepted practices and terminology of archiving, curation and digital preservation apply to this important class of digital artefacts.
Against Many-Worlds Interpretations
Kent, A
1990-01-01
A short foreword has been added for the archive version of this article, which otherwise appears as originally published in 1990, except for the updating of references. The original abstract follows. This is a critical review of the literature on many-worlds interpretations (MWI), with arguments drawn partly from earlier critiques by Bell and Stein. The essential postulates involved in various MWI are extracted, and their consistency with the evident physical world is examined. Arguments are presented against MWI proposed by Everett, Graham and DeWitt. The relevance of frequency operators to MWI is examined; it is argued that frequency operator theorems of Hartle and Farhi-Goldstone-Gutmann do not in themselves provide a probability interpretation for quantum mechanics, and thus neither support existing MWI nor would be useful in constructing new MWI. Comments are made on papers by Geroch and Deutsch that advocate MWI. It is concluded that no plausible set of axioms exists for an MWI that describes known phys...
Added fructose: a principal driver of type 2 diabetes mellitus and its consequences.
DiNicolantonio, James J; O'Keefe, James H; Lucan, Sean C
2015-03-01
Data from animal experiments and human studies implicate added sugars (eg, sucrose and high-fructose corn syrup) in the development of diabetes mellitus and related metabolic derangements that raise cardiovascular (CV) risk. Added fructose in particular (eg, as a constituent of added sucrose or as the main component of high-fructose sweeteners) may pose the greatest problem for incident diabetes, diabetes-related metabolic abnormalities, and CV risk. Conversely, whole foods that contain fructose (eg, fruits and vegetables) pose no problem for health and are likely protective against diabetes and adverse CV outcomes. Several dietary guidelines appropriately recommend consuming whole foods over foods with added sugars, but some (eg, recommendations from the American Diabetes Association) do not recommend restricting fructose-containing added sugars to any specific level. Other guidelines (such as from the Institute of Medicine) allow up to 25% of calories as fructose-containing added sugars. Intake of added fructose at such high levels would undoubtedly worsen rates of diabetes and its complications. There is no need for added fructose or any added sugars in the diet; reducing intake to 5% of total calories (the level now suggested by the World Health Organization) has been shown to improve glucose tolerance in humans and decrease the prevalence of diabetes and the metabolic derangements that often precede and accompany it. Reducing the intake of added sugars could translate to reduced diabetes-related morbidity and premature mortality for populations.
Lima, Elaine C S; Feijo, Márcia B S; Freitas, Maria C J; dos Santos, Edna R; Armando U.O. SABAA-SRUR; Moura, Luciana S M
2012-01-01
Cassava is regarded as the nutritional base of populations in developing countries, and flour, product made of cassava, is the most consumed in the world. The cassava leaves are very rich in vegetable proteins, but a big amount is lost in processing the crop. The objective of this study was to do a sensory evaluation of cassava flour to which a protein concentrate obtained from cassava leaves (CPML) was added. The CPML was obtained from cassava leaves by isoelectric precipitation and added to...
Jones, Phillip W.
2007-01-01
The impact on educational analysis of mainstream international relations (IR) theories is yet to realize its full potential. The problem of education in relation to the construction of world order is considered in relation to core developments in IR theory since the Second World War. In particular, the global architecture of education is seen as a…
Urdang, Lawrence
1990-01-01
Reviews the current state of World English. Subjects addressed include standard accents and dialects, prejudicial attitudes toward nonstandard "local" usages, the use of English as the language of diplomacy, American influences on the language, and the fracturing of English in non-English-speaking countries around the world. (17 references) (JL)
Beegle, Amy C.
2012-01-01
Access to world music resources such as videos and sound recordings have increased with the advent of YouTube and the efforts of music educators working closely with ethnomusicologists to provide more detailed visual and audio information about various musical practices. This column discusses some world music resources available for music…
Fermentation. Third World Science.
Jones, Natalie; Hughes, Wyn
This unit, developed by the Third World Science Project, is designed to add a multicultural element to existing science syllabi (for students aged 11-16) in the United Kingdom. The project seeks to develop an appreciation of the: boundless fascination of the natural world; knowledge, skills, and expertise possessed by men/women everywhere;…
Flat Currents of Green-Schwarz Superstring in AdS2 × S2 Background
Institute of Scientific and Technical Information of China (English)
无
2006-01-01
From the κ symmetric action of ⅡB string in AdS2 × S2 background given by Zhou, we derive the equations of motion. By using the twisted dual transformation which was introduced by Hou, we construct the flat currents, conserving non-local charge with one free parameter, for the superstring in AdS2 × S2.
Joule-Thomson expansion of the charged AdS black holes
Ökcü, Özgür; Aydıner, Ekrem
2017-01-01
In this paper, we study Joule-Thomson effects for charged AdS black holes. We obtain inversion temperatures and curves. We investigate similarities and differences between van der Waals fluids and charged AdS black holes for the expansion. We obtain isenthalpic curves for both systems in the T- P plane and determine the cooling-heating regions.
Joule-Thomson Expansion of Charged AdS Black Holes
Ökcü, Özgür
2016-01-01
In this paper, we study Joule-Thomson effects for charged AdS black holes. We obtain inversion temperatures and curves. We investigate similarities and differences between van der Waals fluids and charged AdS black holes for the expansion. We obtain isenthalpic curves for both systems in $T-P$ plane and determine the cooling-heating regions.
75 FR 23151 - Noxious Weeds; Old World Climbing Fern and Maidenhair Creeper
2010-05-03
... Inspection Service 7 CFR Parts 360 and 361 Noxious Weeds; Old World Climbing Fern and Maidenhair Creeper... noxious weed regulations by adding Old World climbing fern (Lygodium microphyllum (Cavanilles) R. Brown... Old World climbing fern (Lygodium microphyllum (Cavanilles) R. Brown) and maidenhair creeper...
Static Einstein-Maxwell Black Holes with No Spatial Isometries in AdS Space
Herdeiro, Carlos A. R.; Radu, Eugen
2016-11-01
We explicitly construct static black hole solutions to the fully nonlinear, D =4 , Einstein-Maxwell-anti-de Sitter (AdS) equations that have no continuous spatial symmetries. These black holes have a smooth, topologically spherical horizon (section), but without isometries, and approach, asymptotically, global AdS spacetime. They are interpreted as bound states of a horizon with the Einstein-Maxwell-AdS solitons recently discovered, for appropriate boundary data. In sharp contrast to the uniqueness results for a Minkowski electrovacuum, the existence of these black holes shows that single, equilibrium, black hole solutions in an AdS electrovacuum admit an arbitrary multipole structure.
Static Einstein-Maxwell Black Holes with No Spatial Isometries in AdS Space.
Herdeiro, Carlos A R; Radu, Eugen
2016-11-25
We explicitly construct static black hole solutions to the fully nonlinear, D=4, Einstein-Maxwell-anti-de Sitter (AdS) equations that have no continuous spatial symmetries. These black holes have a smooth, topologically spherical horizon (section), but without isometries, and approach, asymptotically, global AdS spacetime. They are interpreted as bound states of a horizon with the Einstein-Maxwell-AdS solitons recently discovered, for appropriate boundary data. In sharp contrast to the uniqueness results for a Minkowski electrovacuum, the existence of these black holes shows that single, equilibrium, black hole solutions in an AdS electrovacuum admit an arbitrary multipole structure.
Effects of ad placement and type on consumer responses to podcast ads.
Ritter, Eric A; Cho, Chang-Hoan
2009-10-01
The purpose of this study was to understand the effects of podcast ad placement and podcast ad type on consumers' perceived intrusiveness, perceived irritation, attitude toward the ad, and ad avoidance. Our 2 x 2 (traditional ad vs. sponsorship by beginning vs. middle) experimental study found that sponsorships generated better consumer responses than did traditional ads and that podcast ads placed at the beginning of audio podcasts yielded better consumer responses than those placed in the middle. Implications for marketers and advertisers are discussed.
Virtual World Security Inspection
Directory of Open Access Journals (Sweden)
Nicholas Charles Patterson
2012-06-01
Full Text Available Virtual property theft is a serious problem that exists in virtual worlds. Legitimate users of these worlds invest considerable amounts of time, effort and real-world money into obtaining virtual property, but unfortunately, are becoming victims of theft in high numbers. It is reported that there are over 1 billion registered users of virtual worlds containing virtual property items worth an estimated US$50 billion dollars. The problem of virtual property theft is complex, involving many legal, social and technological issues. The software used to access virtual worlds is of great importance as they form the primary interface to these worlds and as such the primary interface to conduct virtual property theft. The security vulnerabilities of virtual world applications have not, to date, been examined. This study aims to use the process of software inspection to discover security vulnerabilities that may exist within virtual world software – vulnerabilities that enable virtual property theft to occur. Analyzing three well know virtual world applications World of Warcraft, Guild Wars and Entropia Universe, this research utilized security analysis tools and scenario testing with focus on authentication, trading, intruder detection and virtual property recovery. It was discovered that all three examples were susceptible to keylogging, mail and direct trade methods were the most likely method for transferring stolen items, intrusion detection is of critical concern to all VWEs tested, stolen items were unable to be recovered in all cases and lastly occurrences of theft were undetectable in all cases. The results gained in this study present the key problem areas which need to be addressed to improve security and reduce the occurrence of virtual property theft.
Ad-Coop Positioning System (ACPS)
DEFF Research Database (Denmark)
Frattasi, Simone; Monti, Marco
2008-01-01
In this paper, we propose an innovative solution for positioning determination in 4G wireless networks by introducing the Ad-Coop Positioning System (ACPS). The ACPS is supported by a hybrid cellular ad-hoc architecture, where the cellular network has a centralized control over the ad......-hoc connections among pairs of mobiles. Specifically, peer-to-peer (P2P) communications are exploited in a mesh fashion within cellular-established clusters for cooperation-aided localization purposes (from that, the word ad-coop is derived). The major contribution of this work is the design of the data fusion...... to conventional hybrid positioning techniques in cellular networks....
Exploring antismoking ads: appeals, themes, and consequences.
Beaudoin, Christopher E
2002-01-01
In this study we seek a descriptive understanding of antismoking television advertising in light of the problem cigarette consumption poses for society today. We establish relationships between ad characteristics and whether ads have a youth or adult orientation, based on a content analysis of 197 antismoking television advertisements produced between 1991 and 1999. The study finds that youth-oriented ads have youth characters, sociability, and humor as common appeals, and social and short-term consequences. In contrast, adult-oriented ads relied on fear appeals and long-term, health-related consequences.
Sales determinants of canned pork products: A world-wide study
DEFF Research Database (Denmark)
Jensen, Nick Norman; Grunert, Klaus G.; Baadsgaard, Allan
1994-01-01
is not generally available from official statistics and other secondary sources, rendering a primary data collection necessary. In the present study, data about these factors was collected for a set of 26 countries. 4. Data analysis showed that, by using appropriate models, about 70% of the variation in sales...... factors: religion, attitude towards meat, pork, and canned pork, usage of product, c) distrib factors: retail structure, outlet characteristics, possibilities for transporting fresh meat, d) competitive factors: primary and secondary competition, tariffs. 3. Information about these factors...
Uotila, U. A.
1978-01-01
In order to use gravity anomalies in geodetic computations and geophysical interpretations, the observed gravity values from which anomalies are derived should be referred to one consistent world wide system. The International Gravity Standardization Net 1971 was adapted by the International Union of Geodesy and Geophysics at Moscow in 1971, the network was result of extensive cooperation by many organizations and individuals around the world. The network contains more than 1800 stations around the world. The data used in the adjustment included more than 25,000 gravimetry, pendulum and absolute measurements.
Clerici, A.; Alimonti, G.
2015-08-01
As energy is the main "fuel" for social and economic development and since energy-related activities have significant environmental impacts, it is important for decision-makers to have access to reliable and accurate data in an user-friendly format. The World Energy Council (WEC) has for decades been a pioneer in the field of energy resources and every three years publishes its flagship report Survey of Energy Resources. A commented analysis in the light of latest data summarized in such a report, World Energy Resources (WER) 2013, is presented together with the evolution of the world energy resources over the last twenty years.
Directory of Open Access Journals (Sweden)
Clerici A.
2015-01-01
Full Text Available As energy is the main “fuel” for social and economic development and since energy-related activities have significant environmental impacts, it is important for decision-makers to have access to reliable and accurate data in an user-friendly format. The World Energy Council (WEC has for decades been a pioneer in the field of energy resources and every three years publishes its flagship report Survey of Energy Resources. A commented analysis in the light of latest data summarized in such a report, World Energy Resources (WER 2013, is presented together with the evolution of the world energy resources over the last twenty years.
From path integrals to tensor networks for the AdS /CFT correspondence
Miyaji, Masamichi; Takayanagi, Tadashi; Watanabe, Kento
2017-03-01
In this paper, we discuss tensor network descriptions of AdS /CFT from two different viewpoints. First, we start with a Euclidean path-integral computation of ground state wave functions with a UV cutoff. We consider its efficient optimization by making its UV cutoff position dependent and define a quantum state at each length scale. We conjecture that this path integral corresponds to a time slice of anti-de Sitter (AdS) spacetime. Next, we derive a flow of quantum states by rewriting the action of Killing vectors of AdS3 in terms of the dual two-dimensional conformal field theory (CFT). Both approaches support a correspondence between the hyperbolic time slice H2 in AdS3 and a version of continuous multiscale entanglement renormalization ansatz. We also give a heuristic argument about why we can expect a sub-AdS scale bulk locality for holographic CFTs.
Configurational Entropy in Brane-world Models: A New Approach to Stability
Correa, R A C
2015-01-01
In this work we investigate the entropic information on thick brane-worlds scenarios and its consequences. The brane-world entropic information is studied for the sine-Gordon model is and hence the brane-world entropic information measure is shown an accurate way for providing the most suitable values for the bulk AdS curvature. Besides, the brane-world configurational entropy is employed to demonstrate a high organisational degree in the structure of the system configuration, for large values of a parameter of the sine-Gordon model but the one related to the AdS curvature. The Gleiser and Stamatopoulos procedure is finally applied in order to achieve a precise correlation between the energy of the system and the brane-world configurational entropy.
Efficacy of adding folic acid to foods.
Fajardo, Violeta; Varela-Moreiras, Gregorio
2012-06-01
In the past, food fortification along with nutritional education and the decrease in food costs relative to income have proven successful in eliminating common nutritional deficiencies. These deficiencies such as goiter, rickets, beriberi, and pellagra have been replaced with an entirely new set of "emergent deficiencies" that were not previously considered a problem [e.g., folate and neural tube defects (NTDs)]. In addition, the different nutrition surveys in so-called affluent countries have identified "shortfalls" of nutrients specific to various age groups and/or physiological status. Complex, multiple-etiology diseases, such as atherosclerosis, diabetes, cancer, and obesity have emerged. Food fortification has proven an effective tool for tackling nutritional deficiencies in populations; but today a more reasonable approach is to use food fortification as a means to support but not replace dietary improvement strategies (i. e. nutritional education campaigns). Folic acid (FA) is a potential relevant factor in the prevention of a number of pathologies. The evidence linking FA to NTD prevention led to the introduction of public health strategies to increase folate intakes: pharmacological supplementation, mandatory or voluntary fortification of staple foods with FA, and the advice to increase the intake of folate-rich foods. It is quite contradictory to observe that, regardless of these findings, there is only limited information on food folate and FA content. Data in Food Composition Tables and Databases are scarce or incomplete. Fortification of staple foods with FA has added difficulty to this task. Globally, the decision to fortify products is left up to individual food manufacturers. Voluntary fortification is a common practice in many countries. Therefore, the "worldwide map of vitamin fortification" may be analyzed. It is important to examine if fortification today really answers to vitamin requirements at different ages and/or physiological states. The
National Oceanic and Atmospheric Administration, Department of Commerce — The World Magnetic Model is the standard model used by the U.S. Department of Defense, the U.K. Ministry of Defence, the North Atlantic Treaty Organization (NATO)...
Institute of Scientific and Technical Information of China (English)
无
2011-01-01
The WHO approves China’s vaccine regulation system The World Health Organization (WHO) said China had complied with international standards for the regulation of vaccines after it completed the assessment procedures at the end of 2010.
The world's biggest experiment
Gregson, Liz
2008-01-01
According to CERN, our understanding of the Universe is about the change. Meet the Imperial alumni and staff who are involved in CERN's Large Hadron Collider, the world's biggest experiment. (3 pages)
National Oceanic and Atmospheric Administration, Department of Commerce — The World Magnetic Model is the standard model used by the U.S. Department of Defense, the U.K. Ministry of Defence, the North Atlantic Treaty Organization (NATO)...
Directory of Open Access Journals (Sweden)
Cristian Încalţărău
2010-06-01
Full Text Available Globalization became more and more prominent during the last decades. There is no way to argue that globalization led to more interconnected economies, facilitating the communication and the collaboration around the world. But where is this going? Doesglobalization mean uniformity or diversity? As the world begins to resemble more, the people are trying to distinguish between them more, which can exacerbate nationalistic feeling. Friedman argues that globalization made the world smaller and flatter, allowing all countries to take chance of the available opportunities equally. But is this really true? Although politic and cultural factors can stand in front of a really flat world, what is the key for Chinese and Indian success and which are theirs perspectives?
2006-01-01
Esilinastus katastroofifilm "World Trade Center" : stsenarist Andrea Berloff : režissöör Oliver Stone : kunstnik Jan Roelfs : osades Nicholas Cage, Michael Pena, Stephen Dorff jpt : Ameerika Ühendriigid 2006. Ka filmi prototüüpidest
National Oceanic and Atmospheric Administration, Department of Commerce — The World Glacier Inventory (WGI) contains information for over 130,000 glaciers. Inventory parameters include geographic location, area, length, orientation,...
Directory of Open Access Journals (Sweden)
Vahram Ayvazyan
2012-07-01
Full Text Available The aim of this paper is to analyze the possibility of having a world government, which world has been facing overarching changes since the end of Cold war, where bipolar world order has evolved into multipolar system through unipolarity. Analysis method in this paper have the sistematics: discussion of human nature and philosophical dimensions vis-à-vis individual, society and government, as well as society of societies; then briefly analyse globalization, the impact of individuals on interdependency of the current international arena and examine the individualism as the ongoing ideology “by individuals and for individuals.”; and then take the conclusion that the world government is not a utopia
Directory of Open Access Journals (Sweden)
MANSUR, R.
2012-12-01
Full Text Available Overcoming the productivity challenge is the main benefit of the 2014 World Cup for Brazilian people. The sustainable development of our cultural tourism industry will catapult the new middle class growing up rate.
Queueing models for mobile ad hoc networks
Haan, de Roland
2009-01-01
This thesis presents models for the performance analysis of a recent communication paradigm: mobile ad hoc networking. The objective of mobile ad hoc networking is to provide wireless connectivity between stations in a highly dynamic environment. These dynamics are driven by the mobility of stations
Value added meat marketing around the globe
DEFF Research Database (Denmark)
Grebitus, Carola; Mueller Loose, Simone
In highly competitive meat markets it is important to offer value added products to consumers. Thus, we need to understand which attributes are especially valued by consumers. This track session will contribute to a better understanding of consumer preferences for value added meats across differe...
Status Report on the Antiproton Decelerator (AD)
Erikson, T; Möhl, D
2001-01-01
CERN's new Antiproton Decelerator (AD) has been delivering a 100 MeV/c antiproton beam to three experiments (ASACUSA, AHENA and ATRAP) since July 10th, 2000. In this status report, we summarise the initial performance of the AD, draw provisional conclusions from the first month of operation and finally give some prospects for the future.
Brane World Cosmological Perturbations
Casali, A G; Wang, B; Casali, Adenauer G.; Abdalla, Elcio; Wang, Bin
2004-01-01
We consider a brane world and its gravitational linear perturbations. We present a general solution of the perturbations in the bulk and find the complete perturbed junction conditions for generic brane dynamics. We also prove that (spin 2) gravitational waves in the great majority of cases can only arise in connection with a non-vanishing anisotropic stress. This has far reaching consequences for inflation in the brane world. Moreover, contrary to the case of the radion, perturbations are stable.
Institute of Scientific and Technical Information of China (English)
2006-01-01
Hangzhou and surrounding communities open their doors to leisure and tourism The 2006 World Leisure Expo opens its doors in the scenic city of Hangzhou, in east China’s Zhejiang Province, from April 22 to October 22. The Expo, which was co-sponsored by the World Leisure Organization (WLO), National Tourism Administration and the Zhejiang Provincial Government, highlights the many recreational facets of Hangzhou.
World competitiveness and agriculture
Directory of Open Access Journals (Sweden)
J. van Zyl
1997-07-01
Full Text Available Against the background of a changing environment in which market factors and greater world trade and competitiveness are increasingly becoming the only criteria for success, a framework for the analysis of world competitiveness is initially developed. This is followed by a discussion on the growth of productivity in agriculture, as well as an exposition of the role of agricultural research. Thirdly, price factors and the terms of trade are discussed, followed by a summary of policy implications.
Fitness World - Fremtidig overlevelse
Rice, Kasper; Klink, Nikolaj; Nielsen, Mie; Carlson, Andre; Boy, Mikkel; Hansen, Alexander
2015-01-01
Our project is a case study with Fitness World as a baseline. Our project will enhance Fitness Worlds penetration on their current position on the market. Our empiricism includes both qualitative and quantitative methodical approaches by the use of an expert interview and a questionnaire survey. These methods contribute and generate general knowledge about the fitness culture in Denmark and the customers in the fitness industry. We have stated a possible strategic opportunity for Fitness Worl...
Clemens Fessler; Claudia Tassotti
2012-01-01
Inside-My-World ist die erste Offline-Plattform, auf der man Freundinnen und Freunde kennenlernen, sich im Chat oder in Foren unterhalten, spannende Games spielen oder ganz einfach das eigene Profil gestalten und auf die Pinnwand seiner Freundinnen und Freunde schreiben kann.Diese Plattform hat den Vorteil, dass zum Einstieg keine Computer und keine Internetverbindung notwendig sind, da sie in jedem Raum, z.B. in einem Klassenzimmer, entstehen kann. Denn Inside-My-World ist ein Soziales Netzw...
Google Advertising Tools Cashing in with AdSense and AdWords
Davis, Harold
2010-01-01
With this book, you'll learn how to take full advantage of Google AdWords and AdSense, the sophisticated online advertising tools used by thousands of large and small businesses. This new edition provides a substantially updated guide to advertising on the Web, including how it works in general, and how Google's advertising programs in particular help you make money. You'll find everything you need to work with AdWords, which lets you generate text ads to accompany specific search term results, and AdSense, which automatically delivers precisely targeted text and image ads to your website.
Mazhari, N S; Bahamonde, Sebastian; Faizal, Mir; Myrzakulov, Ratbay
2016-01-01
The holographic complexity and fidelity susceptibility have been defined as new quantities dual to different volumes in AdS. In this paper, we will use these new proposals to calculate both of these quantities for a variety of interesting deformations of AdS. We obtain the holographic complexity and fidelity susceptibility for an AdS black hole, Janus solution and a solution with cylindrically symmetry, an inhomogeneous background and a hyperscaling violating background. It is observed that the holographic complexity depends on the size of the subsystem for all these solutions and the fidelity susceptibility does not any such dependence.
Geometric Finiteness, Holography and Quasinormal Modes for the Warped AdS_3 Black Hole
Gupta, Kumar S; Sen, Siddhartha; Sivakumar, M
2009-01-01
We show that there exists a precise kinematical notion of holography for the Euclidean warped $AdS_3$ black hole. This follows from the fact that the Euclidean warped $AdS_3$ black hole spacetime is a geometrically finite hyperbolic manifold. For such manifolds a theorem of Sullivan provides a one-to-one correspondence between the hyperbolic structure in the bulk and the conformal structure of its boundary. Using this theorem we obtain the holographic quasinormal modes for the warped $AdS_3$ black hole.
Entropy of Warped Taub-NUT AdS Black String via the Brick Wall Method
Lee, Chong Oh
2014-01-01
When we consider five-dimensional warped Taub-NUT AdS black string with minimally coupled massive scalar field, we calculate an entropy by using the brick wall method. In extremely light effective mass, we find the entropy is proportional to an extra dimension wave number as well as quadratically divergent in a cutoff parameter. After taking zero NUT charge, we find the entropy of warped (AdS) Schwartzshield black hole string has a similar properties in as warped Taub-NUT AdS black string.
Beyond the unitarity bound in AdS/CFT{sub (A)dS}
Energy Technology Data Exchange (ETDEWEB)
Andrade, Tomas [University of California, Santa Barbara (United States); Uhlemann, Christoph [Universitaet Wuerzburg (Germany)
2012-07-01
We study CFTs on dS and AdS spacetimes from a holographic perspective, in particular how the unitarity properties of the boundary theory are reflected in the bulk description. On geometries with an (A)dS conformal boundary we choose mass and boundary conditions for a Klein-Gordon field such that the corresponding CFT operator violates the unitarity bound. We analyze how the non-unitarity is reproduced in the bulk and discuss, for the case of an AdS boundary, prospects for multi-layered AdS/CFT-type dualities.
An improved AFS phase for AdS3 string integrability
Abbott, Michael C
2015-01-01
We propose a number of modifications to the classical term in the dressing phase for integrable strings in AdS3 x S3 x S3 x S1, and check these against existing perturbative calculations, crossing symmetry, and the semiclassical limit of the Bethe equations. The principal change is that the phase for different masses should start with a term Q_1 Q_2, like the one-loop AdS3 dressing phase, rather than Q_2 Q_3 as for the original AdS5 AFS phase.
Thermodynamic geometry and phase transitions of AdS braneworld black holes
Chaturvedi, Pankaj; Sengupta, Gautam
2017-02-01
The thermodynamics and phase transitions of charged RN-AdS and rotating Kerr-AdS black holes in a generalized Randall-Sundrum braneworld are investigated in the framework of thermodynamic geometry. A detailed analysis of the thermodynamics, stability and phase structures in the canonical and the grand canonical ensembles for these AdS braneworld black holes are described. The thermodynamic curvatures for both these AdS braneworld black holes are computed and studied as a function of the thermodynamic variables. Through this analysis we illustrate an interesting dependence of the phase structures on the braneworld parameter for these black holes.
Directory of Open Access Journals (Sweden)
N.S. Mazhari
2017-03-01
Full Text Available The holographic complexity and fidelity susceptibility have been defined as new quantities dual to different volumes in AdS. In this paper, we will use these new proposals to calculate both of these quantities for a variety of interesting deformations of AdS. We obtain the holographic complexity and fidelity susceptibility for an AdS black hole, Janus solution, a solution with cylindrical symmetry, an inhomogeneous background and a hyperscaling violating background. It is observed that the holographic complexity depends on the size of the subsystem for all these solutions and the fidelity susceptibility does not have any such dependence.
Various types of phase transitions in the AdS soliton background
Peng, Yan; Wang, Bin
2011-01-01
We study the basic holographic insulator and superconductor phase transition in the AdS soliton background by generalizing the spontaneous breaking of a global U(1) symmetry to occur via St$\\ddot{u}$ckelberg mechanism. We construct the soliton solutions with backreaction and examine the effects of the backreaction on the condensation of the scalar hair in the generalized St$\\ddot{u}$ckelberg Lagrangian. We disclose rich physics in various phase transitions. In addition to the AdS soliton configuration, we also examine the property of the phase transition in the AdS black hole background.
Phase Transition and Clapeyon Equation of Black Hole in Higher Dimensional AdS Spacetime
Zhao, Hui-Hua; Ma, Meng-Sen; Zhao, Ren
2014-01-01
By Maxwell equal area law we study the phase transition in higher dimensional Anti-de Sitter (AdS) Reissner-Nordstr\\"{o}m (RN) black hole and Kerr black hole in this paper. The coexisting region of the two phases involved in the phase transition is found and the coexisting curves are shown in $P-T$ figures. We also analytically investigate the parameters which affect the coexisting curves. To better compare with ordinary thermodynamic systems, the Clapeyon equation is derived for higher dimensional AdS black holes. This paper can help to deepen the understanding of the phase transition and phase structure of AdS black holes.
Boundary action of free AdS higher-spin gauge fields and the holographic correspondence
Joung, Euihun
2011-01-01
We determine the boundary terms of the free higher-spin action which reproduce the AdS Fronsdal equations in an AdS manifold with a finite distance boundary. The boundary terms are further constrained by the gauge invariance of the total action. We show that, for spins larger than two, no local boundary term can restore the full gauge symmetry, and the broken symmetry corresponds to higher-spin Weyl transformations on the boundary CFT. The boundary action is used for the evaluation of the on-shell higher-spin AdS action in terms of the boundary data given by a conformal higher-spin field.
On circular strings in (AdS3 × S 3)ϰ
Banerjee, Aritra; Panigrahi, Kamal L.
2016-09-01
The so called one-parameter (often called ϰ) deformed AdS string sigma models have attracted a lot of attention lately in the study of integrability in string theory. We construct various circular string solutions in the (AdS3 × S 3) ϰ background and describe the characteristics of such solutions qualitatively. We study the Bohr-Sommerfeld like quantization for these string states to characterise the motion. Further we find a `long' string limit of such circular strings in the ϰ-deformed AdS3 and find a novel dependence of the oscillation number on the energy in the next to leading order expansion.
On circular strings in $(AdS_3 \\times S^3)_{\\varkappa}$
Banerjee, Aritra
2016-01-01
The so called one-parameter (often called $\\varkappa$) deformed $AdS$ string sigma models have attracted a lot of attention lately in the study of integrability in string theory. We construct various circular string solutions in the $(AdS_3 \\times S^3)_{\\varkappa}$ background and describe the characteristics of such solutions qualitatively. We study the Bohr-Sommerfeld like quantization for these string states to characterise the motion. Further we find a `long' string limit of such circular strings in the $\\varkappa$-deformed $AdS_3$ and find a novel dependence of the oscillation number on the energy in the next to leading order expansion.
[Rapid analysis of added ingredients in heroin].
Wang, Ji-fen; Yu, Jing; Guo, Xin; Sun, Xing-long; Wang, Ding-fang
2011-07-01
The method of rapid analysis of added ingredients in heroin was studied in the present paper. Adding sucrose, fructose, glucose, starch, caffeine and phenacetin to heroin with a certain percentage, the changes in the infrared spectrum with the concentration of heroin increasing and the detection limit of the additives were determined. Whether or not heroin can be detected in the sample with high concentration of added ingredients was studied using Raman spectroscopy. Similarly, in high purity of heroin, whether or not Raman spectroscopy can detect the added ingredients was tested. Through systematic experiments, the results showed that: using infrared spectroscopy and Raman spectroscopy to test the added ingredients of heroin is a rapid and effective method. Each has both advantages and disadvantages. We should select the appropriate method according to the actual cases.
The concept of added value of FM
DEFF Research Database (Denmark)
2012-01-01
Purpose: This chapter presents research perspectives and theoretical reflections on the concept of added value of FM from a variety of academic fields. Methodology: A literature review of the most influential journals within the academic fields of Facilities Management (FM), Corporate Real Estate...... conceptualization of the concept of added value of FM is of utmost importance for further research into the added value of FM and well-considered, evidence- based Value Adding Management in practice. Research limitations: Due to limited time not all FM-related journals could be included in the literature review...... Management (CREM) and Business to Business Marketing (B2B Marketing). Findings: The research shows different definitions and focus points, dependent on the academic field and the area of application. The different research perspectives explored a holistic view on the added value of FM by the integration...
Ishii, Takaaki
2015-01-01
We study nonlinear dynamics of the flux tube between an external quark-antiquark pair in $\\mathcal{N}=4$ super Yang-Mills theory using the AdS/CFT duality. In the gravity side, the flux tube is realized by a fundamental string whose endpoints are attached to the AdS boundary. We perturb the endpoints in various ways and numerically compute the time evolution of the nonlinearly oscillating string. As a result, cusps can form on the string, accompanied by weak turbulence and power law behavior in the energy spectrum. When cusps traveling on the string reach the boundary, we observe the divergence of the force between the quark and antiquark. Minimal amplitude of the perturbation below which cusps do not form is also investigated. No cusp formation is found when the string moves in all four AdS space directions, and in this case an inverse energy cascade follows a direct cascade.
Recent development in wireless sensor and ad-hoc networks
Li, Xiaolong; Yang, Yeon-Mo
2015-01-01
Wireless Sensor Network (WSN) consists of numerous physically distributed autonomous devices used for sensing and monitoring the physical and/or environmental conditions. A WSN uses a gateway that provides wireless connectivity to the wired world as well as distributed networks. There are many open problems related to Ad-Hoc networks and its applications. Looking at the expansion of the cellular infrastructure, Ad-Hoc network may be acting as the basis of the 4th generation wireless technology with the new paradigm of ‘anytime, anywhere communications’. To realize this, the real challenge would be the security, authorization and management issues of the large scale WSNs. This book is an edited volume in the broad area of WSNs. The book covers various chapters like Multi-Channel Wireless Sensor Networks, its Coverage, Connectivity as well as Deployment. It covers comparison of various communication protocols and algorithms such as MANNET, ODMRP and ADMR Protocols for Ad hoc Multicasting, Location Based C...
Energy Technology Data Exchange (ETDEWEB)
Freivogel, Ben; /Stanford U., Phys. Dept. /LBL, Berkeley; Hubeny, Veronika E.; /LBL, Berkeley /Durham U., Dept. of Math.; Maloney, Alexander; /Stanford U., Phys. Dept.; Myers, Rob; /Perimeter Inst. Theor. Phys. /Waterloo U.; Rangamani, Mukund; /LBL, Berkeley /Durham U., Dept. of Math.; Shenker, Stephen; /Stanford U., Phys. Dept.
2005-10-07
We study the realization of inflation within the AdS/CFT correspondence. We assume the existence of a string landscape containing at least one stable AdS vacuum and a (nearby) metastable de Sitter state. Standard arguments imply that the bulk physics in the vicinity of the AdS minimum is described by a boundary CFT. We argue that large enough bubbles of the dS phase, including those able to inflate, are described by mixed states in the CFT. Inflating degrees of freedom are traced over and do not appear explicitly in the boundary description. They nevertheless leave a distinct imprint on the mixed state. Analytic continuation allows us, in principle, to recover a large amount of nonperturbatively defined information about the inflating regime. Our work also shows that no scattering process can create an inflating region, even by quantum tunneling, since a pure state can never evolve into a mixed state under unitary evolution.We study the realization of inflation within the AdS/CFT correspondence. We assume the existence of a string landscape containing at least one stable AdS vacuum and a (nearby) metastable de Sitter state. Standard arguments imply that the bulk physics in the vicinity of the AdS minimum is described by a boundary CFT. We argue that large enough bubbles of the dS phase, including those able to inflate, are described by mixed states in the CFT. Inflating degrees of freedom are traced over and do not appear explicitly in the boundary description. They nevertheless leave a distinct imprint on the mixed state. Analytic continuation allows us, in principle, to recover a large amount of nonperturbatively defined information about the inflating regime. Our work also shows that no scattering process can create an inflating region, even by quantum tunneling, since a pure state can never evolve into a mixed state under unitary evolution.
Utilization of Stone Waste in the Development of Value Added Products: A State of the Art Review
Directory of Open Access Journals (Sweden)
Rajni Lakhani
2014-07-01
Full Text Available The utilisation of stone waste, in the form of mineral admixture as a pozzolanic and non-pozzolanic material for mortar and concrete has received considerable attention in recent years. This interest is part of the widely spread attention directed towards the utilisation of wastes and industrial by-products in order to minimise Portland cement (PC and sand consumption, the utilisationof which being environmentally damaging. Another reason is that mortar and concrete, which contain pozzolanic as well as non-pozzolanic materials, exhibit considerable enhancement in durability properties. This paper reviews work carried out on the use of stone waste as a partial non-pozzolanic replacement for sand in mortar and concrete and in the containment of hazardous wastes. The literature demonstrates that different stone wastes is an effective inert filler which causes great improvement in the pore structure and hence the resistance of the concrete to the action of harmful solutions.
Quantum corrections to supergravity on AdS2×S2
Larsen, Finn; Lisbão, Pedro
2015-04-01
We compute the off-shell spectrum of supergravity on AdS2×S2 by explicit diagonalization of the equations of motion for an effective AdS2 theory where all fields are dualized to scalars and spin-1/2 fermions. We classify all bulk modes as physical, gauge violating, and pure gauge then compute the physical spectrum by explicit cancellation of unphysical modes. We identify boundary modes as physical fields on S2 that are formally pure gauge but with gauge function that is non-normalizable on AdS2. As an application we compute the leading quantum correction to AdS2×S2 as a sum over physical fields including boundary states. The result agrees with a previous computation by Sen [1] where unphysical modes were canceled by ghosts.
A Grassmann Path From AdS$_3$ to Flat Space
Krishnan, Chethan; Roy, Shubho
2013-01-01
We show that interpreting the inverse AdS$_3$ radius $1/l$ as a Grassmann variable results in a formal map from gravity in AdS$_3$ to gravity in flat space. The underlying reason for this is the fact that $ISO(2,1)$ is the Inonu-Wigner contraction of $SO(2,2)$. We show how this works for the Chern-Simons actions, demonstrate how the general (Banados) solution in AdS$_3$ maps to the general flat space solution, and how the Killing vectors, charges and the Virasoro algebra in the Brown-Henneaux case map to the corresponding quantities in the BMS$_3$ case. Our results straightforwardly generalize to the higher spin case: the recently constructed flat space higher spin theories emerge automatically in this approach from their AdS counterparts. We conclude with a discussion of singularity resolution in the BMS gauge as an application.
Impaired cognition in depression and Alzheimer (AD: a gradient from depression to depression in AD
Directory of Open Access Journals (Sweden)
Narahyana Bom de Araujo
2014-09-01
Full Text Available Objective To assess cognition in major depressed (MD, Alzheimer's disease (AD, and depression in AD elderly. Method Subjects were evaluated by Mini Mental, Rey Auditory Verbal Learning Test, Rey Complex Figure, Digit Span, Similarities, Trail Making A/B, Verbal Fluency and Stroop. One-way ANOVA and multivariate models were used to compare the performance of each group on neuropsychological tests. Results We evaluated 212 subjects. Compared to MD, attention, working memory, processing speed and recall showed significantly better in controls. Controls showed significantly higher performance in all cognitive measures, except in attention compared to AD. Verbal fluency, memory, processing speed and abstract reasoning in MD was significantly higher compared to AD. AD was significantly better in general cognitive state than depression in AD. All other cognitive domains were similar. Conclusion A decreasing gradient in cognition appeared from the control to depression in AD, with MD and AD in an intermediate position.
Bridging Context Management Systems in the ad hoc and mobile environments
Pawar, Pravin; Boros, Hanga; Liu, Fei; Heijenk, Geert; Beijnum, van Bert-Jan
2009-01-01
The pervasive computing world in which the context-aware applications are aimed at is constituted of multiple network environments, e.g. ad hoc, mobile and fixed. There exist specialized Context Management Systems (CMSs) addressing context management needs of every network environment and the existe
Adding a medicine to the WHO model list of essential medicines.
Kishore, S P; Herbstman, B J
2009-03-01
Although the concept of essential medicines is not new, the processes that lead to placement of these medicines on the World Health Organization Model List of Essential Medicines are not well understood. Here, we describe the process by which we added a class of drugs, statins, to the Model List to help combat the growing global epidemic of cardiovascular disease.
EXAMINING THE MOVEMENTS OF MOBILE NODES IN THE REAL WORLD TO PRODUCE ACCURATE MOBILITY MODELS
Directory of Open Access Journals (Sweden)
TANWEER ALAM
2010-09-01
Full Text Available All communication occurs through a wireless median in an ad hoc network. Ad hoc networks are dynamically created and maintained by the individual nodes comprising the network. Random Waypoint Mobility Model is a model that includes pause times between changes in destination and speed. To produce a real-world environment within which an ad hoc network can be formed among a set of nodes, there is a need for the development of realistic, generic and comprehensive mobility models. In this paper, we examine the movements of entities in the real world and present the production of mobility model in an ad hoc network.
Study of ADS-B Data Evaluation
Institute of Scientific and Technical Information of China (English)
ZHANG Jun; LIU Wei; ZHU Yanbo
2011-01-01
In western China,the terrain and meteorological conditions are so complex that it is not suitable to construct new radar stations.Automatic dependent surveillance-broadcast(ADS-B) is a totally new surveillance method,so before practically applied and operated in China,abundant tests and evaluations are necessary to validate the performance of ADS-B and guarantee the operational security.During the flight tests,we collect the data of radar,ADS-B and high accuracy position and compare the performance of ADS-B with radar based on high accuracy position.To solve the asynchronous problem among radar data,ADS-B data and real-time kinematic(RTK) data caused by different update rates,this article proposes the technique of synchronizing multi-surveil- lance data by extrapolating from the data of low update rate to high update rate according to velocity and heading.Meanwhile,because radar data,ADS-B data and RTK data are expressed in different coordinates and cannot be compared each other,this article provides a method to unifying the coordinates of multi-surveillance data.By the analysis and evaluation,we can conclude that the performance of ADS-B is better than radar.
Ad Hoc Network Securing Policy%Ad hoc网络安全策略
Institute of Scientific and Technical Information of China (English)
刘志远; 张曼曼
2006-01-01
本文首先介绍了Ad hoc网络的产生、定义、特点和应用,然后在探讨Ad hoc网络的安全需求的基础上,着重分析了移动Ad hoc网络易于遭受的攻击,最后讨论并提出了Ad Hoc网络的一些安全策略.
Yangian of AdS_3/CFT_2 and its deformation
Regelskis, Vidas
2015-01-01
We construct highest-weight modules and a Yangian extension of the centrally extended superalgebra appearing in the worldsheet scattering associated with the AdS_3 /CFT_2 duality, and show a link to the Yangian of AdS_5/CFT_4. We also consider a quantum deformation of this superalgebra, its modules and a quantum affine extension of the Drinfeld-Jimbo type which describes deformed worldsheet scattering.
Half BPS states in AdS_5 x Y^{p,q}
Gava, Edi; Milanesi, Giuseppe; O'Loughlin, Martin
2008-01-01
We study a class of solutions of IIB Supergravity which are asymptotically AdS_5 x Y^{p,q}. They have an R x SO(4) x SU(2) x U(1) isometry and preserve half of the 8 supercharges of the background geometry. They are described by a set of second order differential equations that we have found and analysed in a previous paper, where we studied 1/8 BPS states in the maximally supersymmetric AdS_5 x S^5 background. These geometries correspond to certain chiral primary operators of the N=1 superconformal quiver theories, dual to IIB theory on AdS_5 x Y^{p,q}. We also show how to recover the AdS_5 x Y^{p,q} backgrounds by suitably doubling the number of preserved supersymmetries. We then solve the differential equations perturbatively in a large AdS_5 radius expansion, imposing asymptotic AdS_5 x Y^{p,q} boundary conditions. We compute the global baryonic and mesonic charges, including the R-charge. As for the computation of the mass, i.e. the conformal dimension D of the dual field theory operators, which is notor...
Service placement in ad hoc networks
Wittenburg, Georg
2012-01-01
Service provisioning in ad hoc networks is challenging given the difficulties of communicating over a wireless channel and the potential heterogeneity and mobility of the devices that form the network. Service placement is the process of selecting an optimal set of nodes to host the implementation of a service in light of a given service demand and network topology. The key advantage of active service placement in ad hoc networks is that it allows for the service configuration to be adapted continuously at run time. ""Service Placement in Ad Hoc Networks"" proposes the SPi service placement fr
Flavonoids in the development of functional meat products: A review
Directory of Open Access Journals (Sweden)
Pramod K. Singh
2013-06-01
Full Text Available Flavonoids or bioflavonoids are unique low molecular weight ubiquitous polyphenolic compounds produced by plants during their metabolic activities as a secondary metabolites and responsible for major organoleptic characteristics and health benefits of plant derived foods. The flavonoids are potent antioxidants agents and protect the cells by scavenging and inhibiting the production and initiation of free radicals, superoxide anions and lipid peroxy radicals. Besides potent antioxidant capacity, flavonoids also shows antimicrobial, antimutagenic, antidiabetic, antithrombosis, antirheumatic, antiatherosclerotic, antiallergic, anti-inflammatory, antiulcers and hepatoprotectives and better termed as neutraceuticals. The antioxidant capacity of meat is very low and this can be increased by adding flavonoids in meat during processing in the form of plant parts rich in flavonoids such as seeds, fruit skin or peel, bark and flower as raw or in extract form without comprising the sensory attributes of meat and meat products. [Vet World 2013; 6(8.000: 573-578
DEFF Research Database (Denmark)
Gürsimsek, Remzi Ates
2014-01-01
The online social platforms known as virtual worlds present their users various affordances for avatar based co-presence, social interaction and provide tools for collaborative content creation, including objects, textures and animations. The users of these worlds navigate their avatars as personal...... mediators in 3D virtual space to collaborate and co-design the digital content. These co-designers are also the residents of these worlds, as they socialize by building inworld friendships. This article presents a social semiotic analysis of the three-dimensional virtual places and artifacts in the virtual...... the audio-visual characteristics of designing in multi-user virtual environments generate experiential, interpersonal and textual meaning potentials....
Directory of Open Access Journals (Sweden)
PETER COLLECOTT
2014-05-01
Full Text Available It is common ground amongst almost all commentators that the world has changed radically over the past 25 years – the 25 years since the fall of the Berlin Wall heralded the ending of the Cold War, the reunification of a tragically divided Europe, and the acceleration of the process of globalisation which has its only comparable period in the decades leading up to the First World War in 1914. When analyzing the Emerging World Order it is important to cover more than Brazil economy or any other individual BRICs or other Emerging Powers. Instead, our analysis will provide a global view about the economic and political global power structures which are evolving and forming before our eyes, and then to talk about the challenges these emerging realities pose for us in Europe, and in the West in general.
Energy Technology Data Exchange (ETDEWEB)
NONE
2011-11-15
The World Energy Insight 2011 is the official publication of the World Energy Council. It includes interviews, articles and case studies from a distinguished panel of World Energy Council Officers, CEOs, government ministers, academics and opinion formers from all areas of the energy sector and provides perspectives from around the globe. Government, industry and NGO's offer both policy and technology perspectives. The insights within this publication add to the work that WEC is doing to provide the forum for energy leaders, along with the on-going WEC studies and programmes on Energy Policies, 2050 Energy Scenarios, Energy Resources & Technologies, Energy for Urban Innovation, Rules Of Energy Trade and Global Energy Access.
Dugic, M
2011-01-01
The quantum Universe can be decomposed into subsystems in different ways. We consider the global linear-canonical-transformations-based decompositions (structures) of the Universe. These structures bear the same physical time and the common the fundamental physical law--the Schrodinger law. The Universe quantum state is unique in every instant of time yet bearing the different forms for the different structures of the Universe. This simple corollary of the universally valid quantum mechanics points out that the intelligent agents in a structure may (globally) affect the other structures--the other "worlds". Locally considered non-spontaneous, such effects may seem "ghostly" within the alternative worlds. This picture of the one and the unique quantum Universe is competitive with both the Everett MWI as well as with the Bohmian pilot-wave interpretation, not yet being inconsistent with the "state collapse" interpretation of quantum mechanics. The "ghostly worlds" interpretation here we introduce may prove irre...
DEFF Research Database (Denmark)
diaspora in order for the unity and renaissance dreamed of to become a reality. The chapters in Africana World: From Fragmentation to Unity and Renaissance address colonial and postcolonial African realities with a view to present a holistic and transcontinental appraisal of questions, issues...... engagements with Africa's rich cultural heritage, its lingering contemporary challenges, its multifaceted systems of knowledge and its future in the exciting context of the twenty-first century. Africana World: From Fragmentation to Unity and Renaissance is put together in order to help develop the study...... and challenges that confront the continent. Contributors are drawn from different parts of the world - Africa, Europe and the Americas - and it is this eclectic range of scholarly views that lends a rich historicity to the meaning of Africanity. The book contains multidisciplinary and transdisciplinary...
Rockström, Johan; Schellnhuber, Hans Joachim; Hoskins, Brian; Ramanathan, Veerabhadran; Schlosser, Peter; Brasseur, Guy Pierre; Gaffney, Owen; Nobre, Carlos; Meinshausen, Malte; Rogelj, Joeri; Lucht, Wolfgang
2016-10-01
The scale of the decarbonisation challenge to meet the Paris Agreement is underplayed in the public arena. It will require precipitous emissions reductions within 40 years and a new carbon sink on the scale of the ocean sink. Even then, the world is extremely likely to overshoot. A catastrophic failure of policy, for example, waiting another decade for transformative policy and full commitments to fossil-free economies, will have irreversible and deleterious repercussions for humanity's remaining time on Earth. Only a global zero carbon roadmap will put the world on a course to phase-out greenhouse gas emissions and create the essential carbon sinks for Earth-system stability, without which, world prosperity is not possible.
Energy Technology Data Exchange (ETDEWEB)
Forbes, A.; Van der Linde, C.; Nicola, S.
2009-03-15
In the section World Energy Future of this magazine two articles, two interviews and one column are presented. The article 'A green example to the world' refers briefly to the second World Future Energy Summit in Abu Dhabi, which was held from 18-21 January, 2009. The second article, 'Green Utopia in the desert' attention is paid to the Abu Dhabi government-driven Masdar Initiative. The two interviews concern an interview with BP Alternative Energy ceo Vivienne Cox, and an interview with the founder and CEO of New Energy Finance Michael Liebreich. The column ('An efficient response') focuses on the impact of the economic crisis on energy policy.
Checa, Nicolas; Maguire, John; Barney, Jonathan
2003-08-01
On January 1, 1995, representatives from 76 countries signed the World Trade Organization charter, which for years had been part of a temporary trade agreement. The WTO's emergence as a fully empowered supranational body seemed to reflect the triumph of what the first President Bush had described as the "new world order." That order was based on two assumptions: that a healthy economy and a sound financial system make for political stability, and that countries in business together do not fight each other. The number one priority of U.S. foreign policy was thus to encourage the former Communist countries of Europe and the developing nations in Latin America, Asia, and Africa to adopt business-friendly policies. Private capital would flow from the developed world into these countries, creating economic growth. It sounded too good to be true, and so it proved. The new world order of Bush père and his successor, Bill Clinton, has been replaced by the new world disorder of Bush fils. Under the second Bush's administration, the economic and political rationale-behind the Washington consensus of the 1990s has unraveled, forcing a radical change in our perceptions of which countries are safe for business. Negotiating this new environment will require companies to more rigorously evaluate political events and more carefully assess the links between political, economic, and financial risk factors. They'll need to be more selective about which markets to enter, and they'll need to think differently about how to position themselves in those markets. The geopolitical events of the past year, the Bush administration's global war on terror, as well as ongoing convulsions in traditional political and economic relationships must be understood and managed by corporate leaders worldwide. With careful analysis, business leaders can increase their companies' visibility and better respond to the uncertainties of the new world disorder.
Profiling value added position in FM
DEFF Research Database (Denmark)
Katchamart, Akarapong
organizations can best add value. Based on comprehensive literature studies and 7 case studies of private and public organisations from Denmark, Holland, Hong Kong and Thailand, the dissertation analyses, how FM organizations can best create added value. From the analyses the following four value added...... - FM organizations influence the business productivities and outcome Each type of value added requires specific conditions and contingencies involved. This research thus offers a visual aid tool, “FM product-process matrix”, to assist practitioners to indicate their existing circumstances and contexts...... the unarticulated notions of added value from FM organization and activities. It will broaden the managerial perception and discussion on FM provision ´s abilities and capabilities. The results are besides the field of FM also of relevance for management of other service industries and functions....
Nastase, Horatiu
2007-01-01
These lectures present an introduction to AdS-CFT, and are intended both for begining and more advanced graduate students, which are familiar with quantum field theory and have a working knowledge of their basic methods. Familiarity with supersymmetry, general relativity and string theory is helpful, but not necessary, as the course intends to be as self-contained as possible. I will introduce the needed elements of field and gauge theory, general relativity, supersymmetry, supergravity, strings and conformal field theory. Then I describe the basic AdS-CFT scenario, of ${\\cal N}=4 $ Super Yang-Mills's relation to string theory in $AdS_5\\times S_5$, and applications that can be derived from it: 3-point functions, quark-antiquark potential, finite temperature and scattering processes, the pp wave correspondence and spin chains. I also describe some general properties of gravity duals of gauge theories.
Microbial production of value-added nutraceuticals.
Wang, Jian; Guleria, Sanjay; Koffas, Mattheos A G; Yan, Yajun
2016-02-01
Nutraceuticals are important natural bioactive compounds that confer health-promoting and medical benefits to humans. Globally growing demands for value-added nutraceuticals for prevention and treatment of human diseases have rendered nutraceuticals a multi-billion dollar market. However, supply limitations and extraction difficulties from natural sources such as plants, animals or fungi, restrict the large-scale use of nutraceuticals. Metabolic engineering via microbial production platforms has been advanced as an eco-friendly alternative approach for production of value-added nutraceuticals from simple carbon sources. Microbial platforms like the most widely used Escherichia coli and Saccharomyces cerevisiae have been engineered as versatile cell factories for production of diverse and complex value-added chemicals such as phytochemicals, prebiotics, polysaccaharides and poly amino acids. This review highlights the recent progresses in biological production of value-added nutraceuticals via metabolic engineering approaches.
Trust Based Routing in Ad Hoc Network
Talati, Mikita V.; Valiveti, Sharada; Kotecha, K.
Ad Hoc network often termed as an infrastructure-less, self- organized or spontaneous network.The execution and survival of an ad-hoc network is solely dependent upon the cooperative and trusting nature of its nodes. However, this naive dependency on intermediate nodes makes the ad-hoc network vulnerable to passive and active attacks by malicious nodes and cause inflict severe damage. A number of protocols have been developed to secure ad-hoc networks using cryptographic schemes, but all rely on the presence of trust authority. Due to mobility of nodes and limitation of resources in wireless network one interesting research area in MANET is routing. This paper offers various trust models and trust based routing protocols to improve the trustworthiness of the neighborhood.Thus it helps in selecting the most secure and trustworthy route from the available ones for the data transfer.
Multilevel security model for ad hoc networks
Institute of Scientific and Technical Information of China (English)
Wang Changda; Ju Shiguang
2008-01-01
Modern battlefield doctrine is based on mobility, flexibility, and rapid response to changing situations.As is well known, mobile ad hoc network systems are among the best utilities for battlefield activity. Although much research has been done on secure routing, security issues have largely been ignored in applying mobile ad hoc network theory to computer technology. An ad hoc network is usually assumed to be homogeneous, which is an irrational assumption for armies. It is clear that soldiers, commanders, and commanders-in-chief should have different security levels and computation powers as they have access to asymmetric resources. Imitating basic military rank levels in battlefield situations, how multilevel security can be introduced into ad hoc networks is indicated, thereby controlling restricted classified information flows among nodes that have different security levels.
The Tetrahedron Zamolodchikov Algebra and the AdS5 x S5 S-matrix
Mitev, Vladimir; Tsuboi, Zengo
2012-01-01
The S-matrix of the AdS5 x S5 string theory is a tensor product of two centrally extended su(2|2) S-matrices, each of which is related to the R-matrix of the Hubbard model. The R-matrix of the Hubbard model was first found by Shastry, who ingeniously exploited the fact that, for zero coupling, the Hubbard model can be decomposed into two XX models. In this article, we review and clarify this construction from the AdS/CFT perspective and investigate the implications this has for the AdS5 x S5 S-matrix.
Directory of Open Access Journals (Sweden)
Clemens Fessler
2012-03-01
Full Text Available Inside-My-World ist die erste Offline-Plattform, auf der man Freundinnen und Freunde kennenlernen, sich im Chat oder in Foren unterhalten, spannende Games spielen oder ganz einfach das eigene Profil gestalten und auf die Pinnwand seiner Freundinnen und Freunde schreiben kann.Diese Plattform hat den Vorteil, dass zum Einstieg keine Computer und keine Internetverbindung notwendig sind, da sie in jedem Raum, z.B. in einem Klassenzimmer, entstehen kann. Denn Inside-My-World ist ein Soziales Netzwerk in Form eines Rollenspiels für Gruppen, z.B. SchülerInnen, LehrerInnen oder Eltern.
Institute of Scientific and Technical Information of China (English)
VALERIE SARTOR
2010-01-01
@@ Pilafs, risottos, soups, snacks, paellas,stuffing, vinegars, wines and desserts-rice is used all over the world in myriad ways as food and drink.Although rice is one of the world's most ancient foods and it is impossible to know exactly where and when cultivation of this marvelous grain began, China is popularly acknowledged as the homeland of rice. Chinese people have many legends about rice. Some describe a benevolent goddess in silk robes whose gown accidentally picked up stray rice grains, which she dropped from the heavens to humans below. It's also said that Shennong, the Divine Farmer in Chinese myth, sowed the first rice on earth.
1991-12-01
It has been estimated that by the year 2006, the proportion of the world's population residing in cities will for the 1st time exceed 50%. The entire urban population will be living on 1% of the earth's surface. Rapid growth of cities is largely limited to developing countries, where about 9/10 of urban growth is expected to occur in coming decades. Urban growth in developing countries is due to high fertility as well as inmigration of poor peasants seeking a better life. The current growth rate of Third World cities is 3.6% annually, which signifies doubling of the population in 20 years. Paris required over a century to grow from 547,000 to 3 million, but Lagos grew from 700,000 to 5.6 million in 20 years and Cairo grew by 6.5 million in 34 years. Immoderate population growth places a great strain on cities attempting to provide basic services. Only a few authoritarian governments have succeeded in limiting immigration to their metropolitan areas. Rapidly growing cities have become symbols not only of poverty and social deterioration, but of ecological destruction, contamination, and lack of health. Air pollution, waste management, and the water supply are 3 of the most serious problems of hygiene and sanitation in the world's cities. Air pollution is caused by various factors including car exhausts and coal burning. According to World Health Organization data, less than 60% of Third World housing has access to an adequate sanitary system. 90% of sewage is not treated before elimination. And millions of persons with no potable water supply are obliged to consume contaminated water or to use their scarce resources to buy water. Many cities lose up to 60% of their scarce water supplies through leaking pipes. If these pipes were repaired, and the loss amounted to the 12% typical of the US and Great Britain, this single measure would double the volume of potable water available. The lack of social balance is at the root of urban problems in the Third World. 600
The Flying Laboratory for the Observation of ADS-B Signals
Directory of Open Access Journals (Sweden)
Raymond Francis
2011-01-01
Full Text Available Automatic dependent surveillance-broadcast (ADS-B is a system in which aircraft continually transmit their identity and GPS-derived navigational information. ADS-B networks for air traffic monitoring have already been implemented in areas around the world, but ground stations cannot be installed in midocean and are difficult to maintain in the Arctic, leaving a coverage gap for oceanic and high latitude airspace. A potential solution for worldwide tracking of aircraft is through the monitoring of aircraft-transmitted ADS-B signals using satellite-borne receivers. To investigate this possibility, a high altitude balloon experiment was carried out in June 2009 to determine if ADS-B signals can be detected from near space. The Flying Laboratory for the Observation of ADS-B Transmissions (FLOAT was the first stratospheric platform to collect ADS-B data. The FLOAT mission successfully demonstrated the reception of ADS-B signals from near space, paving the way to the development of a space-based ADS-B system.
Adding stress plot function to NASTRAN
Katoh, S.
1978-01-01
Stress plot function was developed and added to the NASTRAN level 15.5. Computed stress distribution can be displayed by this function, with vectors showing the principal stresses of the finite elements over the specified portions of the structure. NASTRAN is reviewed in the aspect of plotting capabilities. Stress tensor field is examined in preparation of stress display. Then the stress plot function as added to the NASTRAN is described. A sample plotout by this function is shown.
AdS-Sliced Flavor Branes and Adding Flavor to the Janus Solution
Clark, Adam B; Newman, George M; Rommal, Andrea
2014-01-01
We implement D7 flavor branes in AdS-sliced coordinates on $AdS_5\\times S^5$ with the ansatz that the brane fluctuates only in the warped ($\\mu$) direction in this slicing, which is particularly appropriate for studying the Janus solution. The natural field theory dual in this slicing is $\\mathcal{N}=4$ super Yang-Mills on two copies of $AdS_4$. Branes extending from $\\mu=\\pm\\pi/2$ can end at different locations, giving rise to quarks with piecewise constant mass on each $AdS_4$ half-space, jumping discontinuously between them. A second class of flavor brane solutions exists in this coordinate system, dubbed "continuous" flavor branes, that extend across the entire range of $\\mu$. We propose that the correct dual interpretation of "disconnected" flavor brane in this ansatz is a quark hypermultiplet with constant mass on one of the AdS$_4$ half-spaces with totally reflecting boundary conditions at the boundary of AdS$_4$; whereas the dual interpretation of a continuous flavor brane has totally transparent boun...
Kay, Bernard S
2011-01-01
We discuss the relationship between the bulk-boundary correspondence in Rehren's algebraic holography (and in other 'fixed-background' approaches to holography) and in mainstream 'Maldacena AdS/CFT'. Especially, we contrast the understanding of black-hole entropy from the viewpoint of QFT in curved spacetime -- in the framework of 't Hooft's 'brick wall' model -- with the understanding based on Maldacena AdS/CFT. We show that the brick-wall modification of a Klein Gordon field in the Hartle-Hawking-Israel state on 1+2-Schwarzschild AdS (BTZ) has a well-defined boundary limit with the same temperature and entropy as the brick-wall-modified bulk theory. One of our main purposes is to point out a close connection, for general AdS/CFT situations, between the puzzle raised by Arnsdorf and Smolin regarding the relationship between Rehren's algebraic holography and mainstream AdS/CFT and the puzzle embodied in the 'correspondence principle' proposed by Mukohyama and Israel in their work on the brick-wall approach to...
Integrable strings for AdS/CFT
Borsato, Riccardo
2016-01-01
In this PhD thesis we review some aspects of integrable models related to string backgrounds or their deformations. In the first part we develop methods to obtain exact results in the AdS3/CFT2 correspondence. We consider the AdS_3 x S^3 x T^4 background with pure Ramond-Ramond flux and we find the all-loop worldsheet S-matrix by exploiting the symmetries of the model in light-cone gauge. As we naturally include the massless modes on the worldsheet, we derive the full set of Bethe-Yang equations. In the massive sector we give also a spin-chain description and we write down solutions compatible with crossing for the scalar factors which are not constrained by simmetries. In the second part of the thesis we consider the so-called "eta-deformation" of the superstring on AdS_5 x S^5. We first discuss the effects of the deformation at the level of the bosonic sigma-model, and we match the tree-level worldsheet scattering processes to the expansion of the q-deformed S-matrix. To identify the missing Ramond-Ramond f...
Gauge Symmetries and Holographic Anomalies of Chern-Simons and Transgression AdS Gravity
Mora, Pablo
2014-01-01
We review the issue of gauge and gravitational anomalies with backgrounds, maybe offering a new outlook on some aspects of these questions. We compute the holographic anomalies of hypothetical theories dual, in the sense of the AdS-CFT correspondence, to Chern-Simons AdS gravities. Those anomalies are either gauge anomalies associated to the AdS gauge group of the theory or diffeomorphism anomalies, with each kind related to the other. As a result of using suitable action principles por Chern-Simons AdS gravities, coming from Transgression forms, we obtain finite results without the need for further regularization. Our results are of potential interest for Lovelock gravity theories, as it has been shown that the boundary terms dictated by the transgressions for Chern-Simons gravities are also suitable to regularize Lovelock theories. The Wess-Zumino consistency condition ensures that anomalies of the generic form computed here should appear for these and other theories.
On Thermodynamics of AdS Black Holes in M-Theory
Belhaj, A; Moumni, H EL; Masmar, K; Sedra, M B
2015-01-01
Motivated by a recent work on asymptotically AdS_4 black holes in M-theory, we investigate the thermodynamics and thermodynamical geometry of AdS black holes from M2 and M5-branes. Concretely, we consider AdS black holes in AdS_{p+2}\\times S^{11-p-2}, where p=2,5 by interpreting the number of M2 (and M5-branes) as a thermodynamical variable. We study the corresponding phase transition to examine their stabilities by calculating and discussing various thermodynamical quantities including the chemical potential. Then, we compute the thermodynamical curvatures from the Quevedo metric for M2 and M5-branes geometries to reconsider the stability of such black objects. The Quevedo metric singularities recover similar stability results provided by the phase transition program.
Searching for world domination
Quillen, E
2004-01-01
"Optimists might believe Microsoft suffered a setback last week that will impede its progress toward world domination, but I suspect the company has already found a way to prevail. At issue before the European Union was Microsoft's bundling of its Windows Media Player with its operating system" (1 page)
J. Tinbergen (Jan)
1990-01-01
textabstractA very neat illustration of the skilful use of small, manageable, world models to consider pressing policy questions of great current relevance. Ron Smith, The Economic Journal" Jan Tinbergen, in this book as in his earlier work, has the courage to address central issues. Dietrich Fisher
Faaij, A.P.C.
2012-01-01
In a wide variety of scenarios, policy strategies, and studies that address the future world energy demand and the reduction of greenhouse gas emissions, biomass is considered to play a major role as renewable energy carrier. Over the past decades, the modern use of biomass has increased rapidly in
Institute of Scientific and Technical Information of China (English)
KHAKIMJON Saydaliyev; ALISHER Amanturdiev; MALOXAT Halikova
2008-01-01
@@ Achievements of selection and other theoretical researches on cotton not only in our country,but also world-wide depend on the presence of genetic resources.Uzbek Scientific Research Institute of Selection and Seed Growing of Cotton is a leading center of science on breeding and production of cotton across Central Asia.
World championship in negotiation?
DEFF Research Database (Denmark)
Smolinski, Remigiusz; Kesting, Peter
2013-01-01
The last decade has seen the emergence of several new negotiation competitions around the world.We think the two major drivers of this development are a general trend toward the increasing internationalization of higher education and a recognition of the specific benefits of competitions for nego...
DEFF Research Database (Denmark)
Harste, Gorm
2014-01-01
The world of the future will not be one without wars. The many hopes we have about a future peace governed by a more or less confederal state will not make wars obsolete. Regular wars and irregular wars will continue and probably about different subjects than we are used to. The article proposes ...
Institute of Scientific and Technical Information of China (English)
无
2010-01-01
Ballet, the dance created for court performances in Renaissance Europe that reached into the world of high art in early 17th century France, has long been loved by Chinese. As early as the 1920s, andinto the 1950s and 1960s when the country was alienated from the
DEFF Research Database (Denmark)
Vilslev, Annette Thorsen
, the dissertation investigates the critical negotiation of the novel as a travelling genre in Japan in the beginning of the 20th century, and, more specifically, Sōseki’s work in relation to world literature and affect theory. Sōseki’s work is highly influential in Japan and East Asia, and his novels widely...
Indian Academy of Sciences (India)
Dileep P Jatkar
2003-02-01
We review proposals of brane world models which attempt to combine gauge theories with gravity at TeV scale by conﬁning the gauge theory to a three-brane embedded in higher dimensional bulk. Gravity, however, propagates in the directions transverse to the brane as well.
DEFF Research Database (Denmark)
Jovchelovitch, Sandra; Priego-Hernandez, Jacqueline; Glaveanu, Vlad Petre
2013-01-01
world. In affluent or individualistic public spheres we recognise the classical developmental pathway proposed by Piaget, with a clear increase in the separation between self and society as children grow. Children’s representations are flexible semiotic systems whose form and content interact...
DEFF Research Database (Denmark)
Robertson, Maria Louise Bønnelykke; Rubow, Cecilie
2013-01-01
Drawing on fieldwork in Kiribati and the Cook Islands, this chapter shows how atoll islands and tropical lagoons, considered highly vulnerable to present and future sea level rise, are extraordinary malleable socio-natural worlds. Revolving around sacred islands submerged by sea water, ancient fish...
Cheok, Adrian David; Nijholt, Anton; Romão, Teresa
2014-01-01
Entertainment media are entertainment products and services that rely on digital technology. Mostly the digital entertainment industry is focused on the developed world such as USA, Europe, and Japan. However, due to the decreasing cost of computer and programming technologies, developing countries
Borja, Rhea R.
2006-01-01
This article presents IISME, a U.S. program that can give educators a real-world experience and that can deepen their subject-matter knowledge. It also presents the experiences of some teachers who are into this program. IISME's summer-fellowship program started out with 40 teachers and 12 companies. The group's growth picked up in 2001, when it…
Centers for Disease Control (CDC) Podcasts
2009-09-01
For World Heart Day, learn more about what heart-healthy steps you can take in the workplace. Created: 9/1/2009 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP). Date Released: 9/9/2009.
Marlowe, Stephen
2014-01-01
What happens when a hardened criminal on the run for his life gets mixed up with an all-girl symphony traveling between lesser-populated planets in a futile attempt to bring culture to their rowdy inhabitants? Well, to put it mildly, hijinks ensue. Read Stephen Marlowe's thoroughly entertaining World Beyond Pluto to find out the rest.
Institute of Scientific and Technical Information of China (English)
ZHANG ZHIPING
2010-01-01
@@ An Exhibition of Fine Works of Seal Engraving Art was held in the Cultural Center of the World Expo in Shanghai in mid-August. The exhibition was organized by the Chinese Academy of Seal Engraving of the Chinese Academy of Arts.
Stoltman, Joseph P.
1992-01-01
Addresses the importance of maps for instruction in both history and geography. Suggests that maps have gotten recent attention because of the rapid political changes occurring in Europe and the quincentenary of Columbus' voyage. Discusses different map projections and the importance of media and satellite display of real pictures of the world.…
R. Veenhoven (Ruut)
1995-01-01
textabstractABSTRACT The World Database of Happiness is an ongoing register of research on subjective appreciation of life. Its purpose is to make the wealth of scattered findings accessible, and to create a basis for further meta-analytic studies. The database involves four sections:
1. Bib
Institute of Scientific and Technical Information of China (English)
金碚
2009-01-01
The financial crisis that first struck the United States is unfolding into a worldwide economic recession.When the U.S.coughs,the world catches a cold,now a once-in-acentury cold.This is unexpected to most people,including most economists.It is often said that everything in the
Randall-Sundrum brane-world in modified gravity
Nakada, Hiroshi
2016-01-01
We modify Randall-Sundrum model of brane-world (with two branes) by adding the scalar curvature squared term in five dimensions. We find that it does not destabilize Randall-Sundrum solution to the hierarchy problem of the Standard Model in particle physics.
Pazmino, J.
2012-06-01
(Abstract only) New York City in the late 20th century rose to be a planetary capital for the sciences, not just astronomy. This growth was mainly in the academic sector but a parallel growth occurred in the public and home field. With the millennium crossing, scientists in New York agitated for a celebration of the City as a place for a thriving science culture. In 2008 they began World Science Festival. 2011 is the fourth running, on June 1-5, following the AAVSO/AAS meetings. World Science Festival was founded by Dr. Brian Greene, Columbia University, and is operated through the World Science Foundation. The Festival is "saturation science" all over Manhattan in a series of lectures, shows, exhibits, performances. It is staged in "science" venues like colleges and musea, but also in off-science spaces like theaters and galleries. It is a blend from hard science, with lectures like those by us astronomers, to science-themed works of art, dance, music. Events are fitted for the public, either for free or a modest fee. While almost all events are on Manhattan, effort has been made to geographically disperse them, even to the outer boroughs. The grand finale of World Science Festival is a street fair in Washington Square. Science centers in booths, tents, and pavilions highlight their work. In past years this fair drew 100,000 to 150,000 visitors. The entire Festival attracts about a quarter-million attendees. NYSkies is a proud participant at the Washington Square fair. It interprets the "Earth to the Universe" display, debuting during IYA-2009. Attendance at "Earth..." on just the day of the fair plausibly is half of all visitors in America. The presentation shows the scale and scope of World Science Festival, its relation to the City, and how our astronomers work with it.
Synchronizability of Small-World Networks Generated from a Two-Dimensional Kleinberg Model
Directory of Open Access Journals (Sweden)
Yi Zhao
2013-01-01
Full Text Available This paper investigates the synchronizability of small-world networks generated from a two-dimensional Kleinberg model, which is more general than NW small-world network. The three parameters of the Kleinberg model, namely, the distance of neighbors, the number of edge-adding, and the edge-adding probability, are analyzed for their impacts on its synchronizability and average path length. It can be deduced that the synchronizability becomes stronger as the edge-adding probability increases, and the increasing edge-adding probability could make the average path length of the Kleinberg small-world network go smaller. Moreover, larger distance among neighbors and more edges to be added could play positive roles in enhancing the synchronizability of the Kleinberg model. The lorentz oscillators are employed to verify the conclusions numerically.
Higher spin contributions to holographic fluid dynamics in AdS5/CFT4
Lee, Seungjin; Polyakov, Dimitri
2014-08-01
We calculate the graviton's β function in the AdS string-theoretic sigma model, perturbed by vertex operators for Vasiliev's higher spin gauge fields in AdS5. The result is given by βmn=Rmn+4Tmn(g ,u) (with the AdS radius set to 1 and the graviton polarized along the AdS5 boundary), with the matter stress-energy tensor given by that of conformal holographic fluid in d =4, evaluated at the temperature given by T =1/π. The stress-energy tensor is given by Tmn=gmn+4umun+∑NTmn(N) where u is the vector excitation satisfying u2=-1 and N is the order of the gradient expansion in the dissipative part of the tensor. We calculate the contributions up to N =2. The higher spin excitations contribute to the β function, ensuring the overall Weyl covariance of the matter stress tensor. We conjecture that the structure of gradient expansion in d =4 conformal hydrodynamics at higher orders is controlled by the higher spin operator algebra in AdS5.
The Impact of Ad Characteristics on Adolescents’ Attitudes Towards Antismoking Ads
Directory of Open Access Journals (Sweden)
Domen Bajde
2008-03-01
Full Text Available Smoking exerts a considerable burden not only on those who smoke but just as well on society at large. In response, governments and institutions often resort to advertising which aims to discourage smoking. Unfortunately, our knowledge of the workings of antismoking advertising is detrimentally limited. In particular, the literature delving into the impact of antismoking ad characteristics (e. g., ad content, valence, intensity on the overall effectiveness of antismoking advertising is scarce and contradictory. This empirical study aims to enhance the knowledge of antismoking advertising by presenting results of the survey involving Slovene adolescents. The adolescents were first exposed to advertisements of different antismoking ad contents (for the purpose of this study the term ‘ad content’ refers to types of appeals used in antismoking advertising, ad valence and intensity, and later invited to respond to a number of questions measuring their attitudes toward the ads, their attitudes toward smoking, their intentions to smoke, etc. The results indicate that while the different intensity and valence of ads produce varying attitudes toward the ads, we could not confirm these differences based on ad content. Also, we found that adolescent smokers respond to antismoking ads differently than do their nonsmoking peers. Our findings offer several important implications for antismoking advertisers and the research community interested in the workings of antismoking advertising.
Extended supersymmetric sigma models in AdS_4 from projective superspace
Butter, Daniel; Lindstrom, Ulf; Tartaglino-Mazzucchelli, Gabriele
2012-01-01
There exist two superspace approaches to describe N=2 supersymmetric nonlinear sigma models in four-dimensional anti-de Sitter (AdS_4) space: (i) in terms of N=1 AdS chiral superfields, as developed in arXiv:1105.3111 and arXiv:1108.5290; and (ii) in terms of N=2 polar supermultiplets using the AdS projective-superspace techniques developed in arXiv:0807.3368. The virtue of the approach (i) is that it makes manifest the geometric properties of the N=2 supersymmetric sigma-models in AdS_4. The target space must be a non-compact hyperkahler manifold endowed with a Killing vector field which generates an SO(2) group of rotations on the two-sphere of complex structures. The power of the approach (ii) is that it allows us, in principle, to generate hyperkahler metrics as well as to address the problem of deformations of such metrics. Here we show how to relate the formulation (ii) to (i) by integrating out an infinite number of N=1 AdS auxiliary superfields and performing a superfield duality transformation. We al...
AdS and Lifshitz scalar hairy black holes in Gauss-Bonnet gravity
Chen, Bin; Fan, Zhong-Ying; Zhu, Lu-Yao
2016-09-01
We consider Gauss-Bonnet (GB) gravity in general dimensions, which is nonminimally coupled to a scalar field. By choosing a scalar potential of the type V (ϕ )=2 Λ0+1/2 m2ϕ2+γ4ϕ4 , we first obtain large classes of scalar hairy black holes with spherical/hyperbolic/planar topologies that are asymptotic to locally anti- de Sitter (AdS) space-times. We derive the first law of black hole thermodynamics using Wald formalism. In particular, for one class of the solutions, the scalar hair forms a thermodynamic conjugate with the graviton and nontrivially contributes to the thermodynamical first law. We observe that except for one class of the planar black holes, all these solutions are constructed at the critical point of GB gravity where there exist unique AdS vacua. In fact, a Lifshitz vacuum is also allowed at the critical point. We then construct many new classes of neutral and charged Lifshitz black hole solutions for an either minimally or nonminimally coupled scalar and derive the thermodynamical first laws. We also obtain new classes of exact dynamical AdS and Lifshitz solutions which describe radiating white holes. The solutions eventually become AdS or Lifshitz vacua at late retarded times. However, for one class of the solutions, the final state is an AdS space-time with a globally naked singularity.
Implementation of Recursion Relations in Gluon Scattering Amplitude Calculations in AdS4 /CFT3
Dokmetzoglou, Nikolaos; Kharel, Savan
2017-01-01
The Anti-de Sitter/Conformal Field Theory (AdS/CFT) correspondence is a duality between a theory of gravity in curved-space (AdS) and a conformally-invariant quantum field theory in flat-space (CFT). Scattering amplitudes are observables associated with the probability of the interaction of a given assembly of particles. Gluons, being the exchange particles associated with the strong nuclear force, which holds quarks together to form protons, are abundant byproducts of fundamental particle collisions. Thus, studying gluon scattering amplitudes is an effective way of deepening our understanding of these observables in AdS/CFT. Traditionally, Feynman diagrams have been used to calculate such scattering amplitudes. In this project, we use factorization properties and recursion relations to simplify these calculations. More specifically, we calculate multiple (different helicity combinations) four-point gluon scattering amplitudes in AdS4 /CFT3 (4-D AdS and 3-D CFT) as sums of products of three-point amplitudes. And then we calculate a five-point gluon scattering amplitude in AdS4 /CFT3 by decomposing it into a sum of products of these four-point and three-point amplitudes. Finally we comment on useful identities for checking these amplitudes. This work was supported by a Weinstein Davidson College Research Initiative Summer Research grant.
On the Thermodynamic Geometry and Critical Phenomena of AdS Black Holes
Sahay, Anurag; Sengupta, Gautam
2010-01-01
In this paper, we study various aspects of the equilibrium thermodynamic state space geometry of AdS black holes. We first examine the Reissner-Nordstrom-AdS (RN-AdS) and the Kerr-AdS black holes. In this context, the state space scalar curvature of these black holes are analysed in various regions of their thermodynamic parameter space. This provides important new insights into the structure and significance of the scalar curvature. We further investigate critical phenomena, and the behaviour of the scalar curvature near criticality, for KN-AdS black holes in two mixed ensembles, introduced and elucidated in our earlier work arXiv:1002.2538 [hep-th]. The critical exponents are identical to those in the RN-AdS and Kerr-AdS cases in the canonical ensemble. This suggests an universality in the scaling behaviour near critical points of AdS black holes. Our results further highlight qualitative differences in the thermodynamic state space geometry for electric charge and angular momentum fluctuations of these.
Interpolating from Bianchi Attractors to Lifshitz and AdS Spacetimes
Kachru, Shamit; Saha, Arpan; Samanta, Rickmoy; Trivedi, Sandip P
2013-01-01
We construct classes of smooth metrics which interpolate from Bianchi attractor geometries of Types II, III, VI and IX in the IR to Lifshitz or $AdS_2 \\times S^3$ geometries in the UV. While we do not obtain these metrics as solutions of Einstein gravity coupled to a simple matter field theory, we show that the matter sector stress-energy required to support these geometries (via the Einstein equations) does satisfy the weak, and therefore also the null, energy condition. Since Lifshitz or $AdS_2 \\times S^3$ geometries can in turn be connected to $AdS_5$ spacetime, our results show that there is no barrier, at least at the level of the energy conditions, for solutions to arise connecting these Bianchi attractor geometries to $AdS_5$ spacetime. The asymptotic $AdS_5$ spacetime has no non-normalizable metric deformation turned on, which suggests that furthermore, the Bianchi attractor geometries can be the IR geometries dual to field theories living in flat space, with the breaking of symmetries being either sp...
Vehicular ad hoc networks standards, solutions, and research
Molinaro, Antonella; Scopigno, Riccardo
2015-01-01
This book presents vehicular ad-hoc networks (VANETs) from the their onset, gradually going into technical details, providing a clear understanding of both theoretical foundations and more practical investigation. The editors gathered top-ranking authors to provide comprehensiveness and timely content; the invited authors were carefully selected from a list of who’s who in the respective field of interest: there are as many from Academia as from Standardization and Industry sectors from around the world. The covered topics are organized around five Parts starting from an historical overview of vehicular communications and standardization/harmonization activities (Part I), then progressing to the theoretical foundations of VANETs and a description of the day-one standard-compliant solutions (Part II), hence going into details of vehicular networking and security (Part III) and to the tools to study VANETs, from mobility and channel models, to network simulators and field trial methodologies (Part IV), and fi...
Rostworowski, Andrzej
2016-01-01
We argue that if the degeneracy of the spectrum of linear perturbations of AdS is properly taken into account, there are globally regular, time-periodic, asymptotically AdS solutions (geons) bifurcating from each linear eigenfrequency of AdS.
Economics: An Emerging Small World?
S. Goyal (Sanjeev); M.J. van der Leij (Marco); J.L. Moraga-Gonzalez (José Luis)
2004-01-01
textabstractThis paper examines the small world hypothesis. The first part of the paper presents empirical evidence on the evolution of a particular world: the world of journal publishing economists during the period 1970-2000. We find that in the 1970's the world of economics was a collection of is
Kay, Bernard S.; Ortíz, L.
2014-05-01
We discuss the relationship between the bulk-boundary correspondence in Rehren's algebraic holography (and in other `fixed-background', QFT-based, approaches to holography) and in mainstream string-theoretic `Maldacena AdS/CFT'. Especially, we contrast the understanding of black-hole entropy from the point of view of QFT in curved spacetime—in the framework of 't Hooft's `brick wall' model—with the understanding based on Maldacena AdS/CFT. We show that the brick-wall modification of a Klein-Gordon field in the Hartle-Hawking-Israel state on dimensional Schwarzschild AdS has a well-defined boundary limit with the same temperature and entropy as the brick-wall-modified bulk theory. One of our main purposes is to point out a close connection, for general AdS/CFT situations, between the puzzle raised by Arnsdorf and Smolin regarding the relationship between Rehren's algebraic holography and mainstream AdS/CFT and the puzzle embodied in the `complementarity principle' proposed by Mukohyama and Israel in their work on the brick-wall approach to black hole entropy. Working on the assumption that similar results will hold for bulk QFT other than the Klein-Gordon field and for Schwarzschild AdS in other dimensions, and recalling the first author's proposed resolution to the Mukohyama-Israel puzzle based on his `matter-gravity entanglement hypothesis', we argue that, in Maldacena AdS/CFT, the algebra of the boundary CFT is isomorphic only to a proper subalgebra of the bulk algebra, albeit (at non-zero temperature) the (GNS) Hilbert spaces of bulk and boundary theories are still the `same'—the total bulk state being pure, while the boundary state is mixed (thermal). We also argue from the finiteness of its boundary (and hence, on our assumptions, also bulk) entropy at finite temperature, that the Rehren dual of the Maldacena boundary CFT cannot itself be a QFT and must, instead, presumably be something like a string theory.
Ad Hoc Access Gateway Selection Algorithm
Jie, Liu
With the continuous development of mobile communication technology, Ad Hoc access network has become a hot research, Ad Hoc access network nodes can be used to expand capacity of multi-hop communication range of mobile communication system, even business adjacent to the community, improve edge data rates. For mobile nodes in Ad Hoc network to internet, internet communications in the peer nodes must be achieved through the gateway. Therefore, the key Ad Hoc Access Networks will focus on the discovery gateway, as well as gateway selection in the case of multi-gateway and handover problems between different gateways. This paper considers the mobile node and the gateway, based on the average number of hops from an average access time and the stability of routes, improved gateway selection algorithm were proposed. An improved gateway selection algorithm, which mainly considers the algorithm can improve the access time of Ad Hoc nodes and the continuity of communication between the gateways, were proposed. This can improve the quality of communication across the network.
Banados and SUSY: On Supersymmetry and Minimal Surfaces of Locally AdS3 Geometries
Colgáin, E Ó
2016-01-01
We extend the classification of supersymmetric locally AdS$_3$ geometries, beyond BTZ black holes, to the Ba\\~nados geometries, noting that supersymmetries are in one-to-one correspondence with solutions to the Hill differential condition. We show that the number of global supersymmetries is an orbit invariant quantity and identify geometries with zero, one, two, three and four global supersymmetries. As an application of our classification, we exploit supersymmetry, which is preserved locally in the bulk, to determine space-like co-dimension two surfaces in AdS$_3$. In the process, we by-pass geodesics or mappings of AdS$_3$, neither of which have an analogue in higher dimensions, to recover known Hubeny-Rangamani-Takayanagi surfaces. Our findings suggest supersymmetry can be exploited to find extremal surfaces in holographic entanglement entropy.
Vacuum energy in Einstein-Gauss-Bonnet AdS gravity
Kofinas, G; Kofinas, Georgios; Olea, Rodrigo
2006-01-01
A finite action principle for Einstein-Gauss-Bonnet AdS gravity is presented. The boundary term, which is different for even and odd dimensions, is a functional of the boundary metric, intrinsic curvature and extrinsic curvature. For even dimensions, the boundary term corresponds to the maximal Chern form of the spacetime, and the asymptotic AdS condition for the curvature suffices for the well-posedness of this action. For odd dimensions, the action is stationary under a boundary condition on the variation of the extrinsic curvature. The background-independent Noether charges associated to asymptotic symmetries are found and the Euclidean continuation of the action correctly describes the black hole thermodynamics in the canonical ensemble. In particular, this procedure leads to a covariant formula for the vacuum energy in odd-dimensional asymptotically AdS spacetimes.
Quark confinement due to creation of micro AdS black holes in quarkonium model
Taki, Mehran
2016-01-01
We use the solution of the Dirac equation for quarkonium atom in the 4D Anti de sitter (AdS$_{4}$) space to investigate the effect of the large negative cosmological constant on the phenomenon of quark confinement. We do the required calculations in the AdS$_{4}$ space to indicate that large cosmological constant can describe the quark confinement. In fact using the coulomb potential in Dirac equation while we employ the AdS metric will additionally lead us to a linear potential in the quark-antiquark interaction which can be considered to explain the quark confinement. This confining term is arising essentially from the geometrical features of the space. On the other hand the origin of the large cosmological constant can be justified by assuming the appearance of micro black holes in the recent hadronic collision process which is now current, for instance, at the LHC project.
Vacuum type space-like string surfaces in AdS_3 x S^3
Dorn, Harald; Kalousios, Chrysostomos; Megrelidze, Luka; Wuttke, Sebastian
2010-01-01
We construct and classify all space-like minimal surfaces in AdS_3 x S^3 which globally admit coordinates with constant induced metric on both factors. Up to O(2,2) x O(4) transformations all these surfaces, except one class, are parameterized by four real parameters. The classes of surfaces correspond to different regions in this parameter space and show quite different boundary behavior. Our analysis uses a direct construction of the string coordinates via a group theoretical treatment based on the map of AdS_3 x S^3 to SL(2,R) x SU(2). This is complemented by a cross check via standard Pohlmeyer reduction. After embedding in AdS_5 x S^5 we calculate the regularized area for solutions with a boundary spanned by a four point scattering s-channel momenta configuration.
Higher spin holography and the AdS string sigma model
Polyakov, Dimitri
2013-05-01
We analyse the cubic spin-3 interaction in AdS space using the higher spin extension of the string-theoretic sigma-model constructed in our previous work, whose low energy limit is described by the AdS vacuum solution. We find that, in the leading order of the cosmological constant, the spin-3 correlator on the AdS4 string theory side reproduces the structure of the three-point function of composite operators, quadratic in free fields, in the dual d = 3 vector model. The cancellation of holography violating terms in d = 3 is related to the value of the Liouville background charge in d = 4. This article is part of a special issue of Journal of Physics A: Mathematical and Theoretical devoted to ‘Higher spin theories and holography’.
On thermodynamics of AdS black holes in M-theory
Energy Technology Data Exchange (ETDEWEB)
Belhaj, A. [Universite Sultan Moulay Slimane, Departement de Physique, LIRST, Faculte Polydisciplinaire, Beni Mellal (Morocco); Cadi Ayyad University, High Energy Physics and Astrophysics Laboratory, FSSM, Marrakesh (Morocco); Chabab, M.; Masmar, K. [Cadi Ayyad University, High Energy Physics and Astrophysics Laboratory, FSSM, Marrakesh (Morocco); El Moumni, H. [Cadi Ayyad University, High Energy Physics and Astrophysics Laboratory, FSSM, Marrakesh (Morocco); Universite Ibn Zohr, Departement de Physique, Faculte des Sciences, Agadir (Morocco); Sedra, M.B. [Universite Ibn Tofail, Departement de Physique, LASIMO, Faculte des Sciences, Kenitra (Morocco)
2016-02-15
Motivated by recent work on asymptotically AdS{sub 4} black holes in M-theory, we investigate the thermodynamics and thermodynamical geometry of AdS black holes from M2- and M5-branes. Concretely, we consider AdS black holes in AdS{sub p+2} x S{sup 11-p-2}, where p = 2,5 by interpreting the number of M2- (and M5-branes) as a thermodynamical variable. More precisely, we study the corresponding phase transition to examine their stabilities by calculating and discussing various thermodynamical quantities including the chemical potential. Then we compute the thermodynamical curvatures from the Quevedo metric for M2- and M5-branes geometries to reconsider the stability of such black holes. The Quevedo metric singularities recover similar stability results provided by the phase-transition program. It has been shown that similar behaviors are also present in the limit of large N. (orig.)
A Stochasticity Threshold in Holography and and the Instability of AdS
Basu, Pallab; Saurabh, Ayush
2014-01-01
We give strong numerical evidence that a self-interacting probe scalar field in AdS, with only a few modes turned on initially, will undergo fast thermalization only if it is above a certain energetic threshold. Below the threshold the energy stays close to constant in a few modes for a very long time instead of cascading quickly. This indicates the existance of a Strong Stochasticity Threshold (SST) in holography. The idea of SST is familiar from certain statistical mechanical systems, and we suggest that it exists also in AdS gravity. This would naturally reconcile the generic non-linear instability of AdS observed by Bizon and Rostworowski, with the Fermi-Pasta-Ulam-Tsingou-like quasi-periodocity noticed recently for some classes of initial conditions. We show that our simple set-up captures many of the relevant features of the full gravity-scalar system.
A note on vectorial AdS5/CFT4 duality for spin- j boundary theory
Bae, Jin-Beom; Joung, Euihun; Lal, Shailesh
2016-12-01
The vectorial holographic correspondences between higher-spin theories in AdS5 and free vector models on the boundary are extended to the cases where the latter is described by free massless spin- j field. The dual higher-spin theory in the bulk does not include gravity and can only be defined on rigid AdS5 background with S 4 boundary. We discuss various properties of these rather special higher-spin theories and calculate their one-loop free energies. We show that the result is proportional to the same quantity for spin- j doubleton treated as if it is a AdS5 field. Finally, we consider even more special case where the boundary theory itself is given by an infinite tower of massless higher-spin fields.
QCD Condensates and Holographic Wilson Loops for Asymptotically AdS Spaces
Energy Technology Data Exchange (ETDEWEB)
Quevedo, R. Carcasses [Instituto Balseiro, Centro Atomico Bariloche, 8400 San Carlos de Bariloche (Argentina); CONICET, Rivadavia 1917, 1033 Buenos Aires (Argentina); Goity, Jose L. [Hampton University, Hampton, VA 23668 (United States); Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Trinchero, Roberto C. [Instituto Balseiro, Centro Atomico Bariloche, 8400 San Carlos de Bariloche (Argentina); CONICET, Rivadavia 1917, 1033 Buenos Aires (Argentina)
2014-02-01
The minimization of the Nambu-Goto (NG) action for a surface whose contour defines a circular Wilson loop of radius a placed at a finite value of the coordinate orthogonal to the border is considered. This is done for asymptotically AdS spaces. The condensates of dimension n = 2, 4, 6, 8, and 10 are calculated in terms of the coefficients in the expansion in powers of the radius a of the on-shell subtracted NG action for small a->0. The subtraction employed is such that it presents no conflict with conformal invariance in the AdS case and need not introduce an additional infrared scale for the case of confining geometries. It is shown that the UV value of the gluon condensates is universal in the sense that it only depends on the first coefficients of the difference with the AdS case.
Wireless Ad Hoc Networks%无线特定网络--Ad Hoc网络
Institute of Scientific and Technical Information of China (English)
张筱; 张光昭
2001-01-01
Ad Hoc网络是一种没有固定结构的无线移动网络.介绍了移动Ad Hoc网络(MANETs)的主要特点和与传统有线分组交换网相比的特性,讨论了应用于Ad Hoc网络的路由机制和所需面临的问题.
Bainbridge, William Sims
2010-01-01
This essay introduces the opportunity for theory development and even empirical research on some aspects of astrosociology through today's online virtual worlds. The examples covered present life on other planets or in space itself, in a manner that can be experienced by the user and where the user's reactions may simulate to some degree future human behavior in real extraterrestrial environments: Tabula Rasa, Anarchy Online, Entropia Universe, EVE Online, StarCraft and World of Warcraft. Ethnographic exploration of these computerized environments raises many questions about the social science both of space exploration and of direct contact with extraterrestrials. The views expressed in this essay do not necessarily represent the views of the National Science Foundation or the United States.
World Class Facilities Management
DEFF Research Database (Denmark)
Malmstrøm, Ole Emil; Jensen, Per Anker
2013-01-01
Alle der med entusiasme arbejder med Facilities Management drømmer om at levere World Class. DFM drømmer om at skabe rammer og baggrund for, at vi i Danmark kan bryste os at være blandt de førende på verdensplan. Her samles op på, hvor tæt vi er på at nå drømmemålet.......Alle der med entusiasme arbejder med Facilities Management drømmer om at levere World Class. DFM drømmer om at skabe rammer og baggrund for, at vi i Danmark kan bryste os at være blandt de førende på verdensplan. Her samles op på, hvor tæt vi er på at nå drømmemålet....
Kiefer, C W
1992-04-01
Militarism is a rapidly growing factor in that complex network of social, political and economic causes of ill health among the world's poor. This complex of causes is driving a spiral of class inequality, political instability, and military repression in many less developed nations. These nations share a uniform security doctrine, which has major health impacts. Here five impacts are noted: diversion of resources, suppression of dissent, military classism, environment damage, and crime and terrorism. The demand stimulated by the recent Persian Gulf War for expensive, high-technology weapons may deepen Third World debt and fuel the cycle of poverty, ill health, social unrest, and military oppression. International health workers need to take account of the causes and effects of militarism in their studies of health problems. Their work could be aided by organizations that promote disarmament and environment preservation.
Energy Technology Data Exchange (ETDEWEB)
NONE
2006-11-07
The World Energy Outlook 2006 sets out the IEA's latest projections of world energy supply and demand to 2030 for oil, gas, coal, renewables, nuclear and electricity, plus projections on energy-related CO{sub 2} emissions. The publication is in three parts. Part A: The reference scenario has chapters entitled: Key assumptions; Global Energy Trends; Oil market outlook; Gas market outlook; Coal market outlook; and Power sector outlook. Part B: The alternative policy scenario contains chapters on: Mapping a new energy future; Assessing the cost-effectiveness of alternative policies; Deepening the analysis results by sector; and Getting to and going beyond the alternative policy scenario. Part C: Focus on key topics contains: The impact of higher energy prices; Current trends in oil and gas investment; Prospects for nuclear power; The outlook for biofuels; Energy for coking in developing countries; and Focus on Brazil. 224 figs., 84 tabs., 5 annexes.
Energy Technology Data Exchange (ETDEWEB)
NONE
2010-09-15
The 21st World Energy Congress offers a unique opportunity for all stake-holders of the energy sector to meet and exchange visions, strategies and practices, during four days of very intensive and interesting sessions, round-tables and exhibitions. More than 3,000 energy leaders gather from around the world from both developed and developing countries, from all types of energy, from public and private companies and government organisations, in order to think together about how to bring about a sustainable and acceptable energy future. The truth is that nobody has the choice any longer. All energy leaders have to take decisions every day, and they need to have a clear analysis of what is at stake, what the risks are, and what the solutions can be.
DEFF Research Database (Denmark)
Carlsen, Hjalmar Alexander Bang; Birkbak, Andreas
2016-01-01
do so by examining three specific situations where the operations of Edgerank have been critiqued and defended: First, Facebook’s own response to the critique that social media produce echo chambers. Second, Facebook’s presentation of the main variables in the Edgerank algorithm. Third, social media......Web algorithms like Facebook’s so-called Edgerank algorithm play an increasingly important role in everyday life. The recent surge of research in such algorithms often emphasizes algorithmic orderings as powerful but opaque. In this essay, we propose an alternative reading of the Edgerank algorithm...... marketing blogs about how to handle the algorithm in practice. Based on these events, we construct an ‘internalistic’ account of the rhetoric of Edgerank, opening for an exploration of its moral grammar and the world or dwelling place it assumes and enacts. We find that the world of Edgerank is ordered...
Energy Technology Data Exchange (ETDEWEB)
Pockley, P
1999-05-01
Two announcements have confirmed that the current Australian government intends to realize the unfulfilled dream of the Menzies era for Australia to become a `nuclear nation` by approving a new `research reactor` and a new uranium mine. Meanwhile, the government is working hard to overturn UNESCO`s recommendation to stop the development of the Jabiluka uranium mine. And, an international proposal to store in Australia stockpiles of high level waste from the world`s power stations and decommissioned nuclear weapons has finally come into the open with the revelation that Pangea Resources Australia Pty Ltd has presented a summary proposal to the government. Though rejected, the plan remains active. Central to the rush to capitalise on Australia`s uranium resources is Environment Minister, Senator Robert Hill, whose formal approvals for the reactor and the mine have been legally essential
Online Stochastic Ad Allocation: Efficiency and Fairness
Feldman, Jon; Korula, Nitish; Mirrokni, Vahab S; Stein, Cliff
2010-01-01
We study the efficiency and fairness of online stochastic display ad allocation algorithms from a theoretical and practical standpoint. In particular, we study the problem of maximizing efficiency in the presence of stochastic information. In this setting, each advertiser has a maximum demand for impressions of display ads that will arrive online. In our model, inspired by the concept of free disposal in economics, we assume that impressions that are given to an advertiser above her demand are given to her for free. Our main theoretical result is to present a training-based algorithm that achieves a (1-\\epsilon)-approximation guarantee in the random order stochastic model. In the corresponding online matching problem, we learn a dual variable for each advertiser, based on data obtained from a sample of impressions. We also discuss different fairness measures in online ad allocation, based on comparison to an ideal offline fair solution, and develop algorithms to compute "fair" allocations. We then discuss sev...
Data Confidentiality in Mobile Ad hoc Networks
Aldabbas, Hamza; Janicke, Helge; Al-Bayatti, Ali; 10.5121/ijwmn.2012.4117
2012-01-01
Mobile ad hoc networks (MANETs) are self-configuring infrastructure-less networks comprised of mobile nodes that communicate over wireless links without any central control on a peer-to-peer basis. These individual nodes act as routers to forward both their own data and also their neighbours' data by sending and receiving packets to and from other nodes in the network. The relatively easy configuration and the quick deployment make ad hoc networks suitable the emergency situations (such as human or natural disasters) and for military units in enemy territory. Securing data dissemination between these nodes in such networks, however, is a very challenging task. Exposing such information to anyone else other than the intended nodes could cause a privacy and confidentiality breach, particularly in military scenarios. In this paper we present a novel framework to enhance the privacy and data confidentiality in mobile ad hoc networks by attaching the originator policies to the messages as they are sent between nod...
Secure Clustering in Vehicular Ad Hoc Networks
Directory of Open Access Journals (Sweden)
Zainab Nayyar
2015-09-01
Full Text Available A vehicular Ad-hoc network is composed of moving cars as nodes without any infrastructure. Nodes self-organize to form a network over radio links. Security issues are commonly observed in vehicular ad hoc networks; like authentication and authorization issues. Secure Clustering plays a significant role in VANETs. In recent years, various secure clustering techniques with distinguishing feature have been newly proposed. In order to provide a comprehensive understanding of these techniques are designed for VANETs and pave the way for the further research, a survey of the secure clustering techniques is discussed in detail in this paper. Qualitatively, as a result of highlighting various techniques of secure clustering certain conclusions are drawn which will enhance the availability and security of vehicular ad hoc networks. Nodes present in the clusters will work more efficiently and the message passing within the nodes will also get more authenticated from the cluster heads.
Introduction to AdS/CFT correspondence
Nastase, Horatiu
2015-01-01
Providing a pedagogical introduction to the rapidly developing field of AdS/CFT correspondence, this is one of the first texts to provide an accessible introduction to all the necessary concepts needed to engage with the methods, tools and applications of AdS/CFT. Without assuming anything beyond an introductory course in quantum field theory, it begins by guiding the reader through the basic concepts of field theory and gauge theory, general relativity, supersymmetry, supergravity, string theory and conformal field theory, before moving on to give a clear and rigorous account of AdS/CFT correspondence. The final section discusses the more specialised applications, including QCD, quark-gluon plasma and condensed matter. This book is self-contained and learner-focused, featuring numerous exercises and examples. It is essential reading for both students and researchers across the fields of particle, nuclear and condensed matter physics.
Earthworms increase plant production: a meta- analysis
Groenigen, van J.W.; Lubbers, I.M.; Vos, H.M.J.; Brown, G.G.; Deyn, de G.B.; Groenigen, van K.J.
2014-01-01
To meet the challenge of feeding a growing world population with minimal environmental impact, we need comprehensive and quantitative knowledge of ecological factors affecting crop production. Earthworms are among the most important soil dwelling invertebrates. Their activity affects both biotic and
Dynamic Carpooling Using Wireless Ad-Hoc Network
Directory of Open Access Journals (Sweden)
Abhishek V. Potnis
2014-04-01
Full Text Available The increase in awareness about the conservation of natural resources in today’s world, has led to carpooling becoming a widely followed practice. Carpooling refers to sharing of a vehicle with other passengers, thus reducing the fuel costs endured by the passengers, had they traveled individually. Carpooling helps reduce fuel consumption, thereby helping conserve the natural resources. Conventional Carpooling Portals require the users to register themselves and input their desired departure and destination points. These portals maintain a database of the users and map them with the users, who have registered for their cars to be pooled. This paper proposes a decentralized method of dynamic carpooling using the Wireless Ad-hoc Network, instead of having the users to register on a Web Portal. The user’s device, requesting for the carpool service can directly talk to another user’s device, providing the pooled car, using the Wireless Ad-hoc Network, thereby eliminating the need for the user to connect to the internet to access the web portal.
DEFF Research Database (Denmark)
Ess, Charles; Thorseth, May
2011-01-01
We collect diverse philosophical analyses of the issues and problems clustering around trust online with specific attention to establishing trust in virtual environments. The book moves forward important discussions of how virtual worlds and virtuality are to be defined and understood; the role...... by virtuality, such as virtual child pornography. The introduction further develops a philosophical anthropology, rooted in Kantian ethics, phenomenology, virtue ethics, and feminist perspectives, that grounds a specific approach to ethical issues in virtual environments....
2010-01-01
Members of the World Presidents' Organization enjoy a buffet luncheon during a Jan. 26 visit to NASA's John C. Stennis Space Center. WPO members from several states toured Stennis facilities during a daylong visit that included a river ride with Special Boat Team 22, the U.S. Navy's elite boat warriors group that trains at Stennis. Visiting president also had an opportunity to learn about the ongoing work of the nation's premier rocket engine testing site.
Institute of Scientific and Technical Information of China (English)
无
2011-01-01
Chinese models still have a long way to go A Chinese debutante garnered most of the limelight at the annual Victoria’s Secret Fashion Show in New York in November last year. He Sui, a newcomer to the modeling world, was the focus of many photographers as the dark haired beauty walked down the runway in a mermaid inspired ensemble.He was followed by another Chinese
Institute of Scientific and Technical Information of China (English)
方岩
2004-01-01
“When in Rome, do as the Romans do.”is a famous saying about customs. But what exactly do the Romans and other people do that is so different? Where do women wear tings in their noses to show they are married, for example? Where do people greet each other with a bow rather than a handshake? Here are some other ways people behave and beautify themselves around the world.
2010-01-01
Members of the World Presidents' Organization take a try at 'piloting' a mock-up of the space shuttle cockpit during a Jan. 26 visit to StenniSphere, the museum and visitor center at NASA's John C. Stennis Space Center. WPO members from several states spent the day touring Stennis facilities and learning about the work of the nation's premier rocket engine testing site.
Energy Technology Data Exchange (ETDEWEB)
Poulsen, J. [Vestas Wind Systems A/S, Lem (Denmark)
1996-12-31
Opinions on the world market for wind power are presented in this paper. Reasons contributing to a potential growth in wind power are cited. Increased demand is expected to arise due to increased energy needs and environmental concerns. Barriers, primarily political, to the development of wind energy are assessed. Development is predicted to occur first in countries with a demand for new capacity and political decisions to protect the environment.
World Bank Group
2014-01-01
Every policy relies on explicit or implicit assumptions about how people make choices. Those assumptions typically rest on an idealized model of how people think, rather than an understanding of how everyday thinking actually works. This year’s World Development Report argues that a more realistic account of decision-making and behavior will make development policy more effective. The Report emphasizes what it calls 'the three marks of everyday thinking.' In everyday thinking, people use...
Southworth, Brian
1991-01-01
What is our Universe made of? Where does it come from? Why does it behave as it does? We do not have all the answers to these questions but in recent years we have uncovered a lot of information about the Universe which surrounds us. This search has revealed that, beyond the evidence of our eyes, there is a seething world of tiny particles and messengers which pass between them...
New Features in the ADS Abstract Service
Eichhorn, G.; Accomazzi, A.; Grant, C. S.; Kurtz, M. J.; ReyBacaicoa, V.; Murray, S. S.
2001-11-01
The ADS Abstract Service contains over 2.3 million references in four databases: Astronomy/Astrophysics/Planetary Sciences, Instrumentation, Physics/Geophysics, and Preprints. We provide abstracts and articles free to the astronomical community for all major and many smaller astronomy journals, PhD theses, conference proceedings, and technical reports. These four databases can be queried either separately of jointly. The ADS also has scanned 1.3 million pages in 180,000 articles in the ADS Article Service. This literature archive contains all major Astronomy journals and many smaller journals, as well as conference proceedings, including the abstract books from all the LPSCs back to volume 2. A new feature gives our users the ability to see list of articles that were also read by the readers of a given article. This is a powerful tool to find out what current articles are relevant in a particular field of study. We have recently expanded the citation and reference query capabilities. It allows our users to select papers for which they want to see references or citations and then retrieve these citations/references. Another new capability is the ability to sort a list of articles by their citation count. As usual, users should be reminded that the citations in ADS are incomplete because we do not obtain reference lists from all publishers. In addition, we cannot match all references (e.g. in press, private communications, author errors, some conference papers, etc.). Anyone using the citations for analysis of publishing records should keep this in mind. More work on expanding the citation and reference features is planned over the next year. ADS Home Page http://ads.harvard.edu/
Horizon Conformal Field Theories from $AdS_2$ Black Holes
Halyo, Edi
2015-01-01
We show that the very near horizon region of nonextreme black holes, which can be described by horizon CFTs, are related to $AdS_2$ Rindler spaces. The latter are $AdS_2$ black holes with specific masses and can be described by states of either $D=1$ or $D=2$ CFTs. The central charges of these CFTs and the conformal weights of their states that correspond to the nonextreme black holes exactly match those predicted by the horizon CFTs, providing supporting evidence for this description.
Superradiance Instability of Small Rotating AdS Black Holes in Arbitrary Dimensions
Delice, Özgür
2015-01-01
We investigate the stability of $D$ dimensional singly rotating Myers-Perry-AdS black holes under superradiance against scalar field perturbations. It is well known that small four dimensional rotating or charged AdS black holes are unstable against superradiance instability of a scalar field. Recent works extended the existence of this instability to five dimensional rotating charged AdS black holes or static charged AdS Black holes in arbitrary dimensions. In this work we analytically prove that, rotating small AdS black holes in arbitrary dimensions also show superradiance instability irrespective of the value of the (positive) angular momentum quantum number. To do this we solve the Klein-Gordon equation in the slow rotation, low frequency limit. By using the asymptotic matching technique, we are able to calculate the real and imaginary parts of the correction terms to the frequency of the scalar field due to the presence of the black hole, confirming the presence of superradiance instability. We see that...
Flowing along the edge: spinning up black holes in AdS spacetimes with test particles
Rocha, Jorge V
2014-01-01
We investigate the consequences of throwing point particles into odd-dimensional Myers-Perry black holes in asymptotically anti-de Sitter (AdS) backgrounds. We restrict our attention to the case in which the angular momenta of the background geometry are all equal. This process allows us to test the generalization of the weak cosmic censorship conjecture to asymptotically AdS spacetimes in higher dimensions. We find no evidence for overspinning in D = 5, 7, 9 and 11 dimensions. Instead, test particles carrying the maximum possible angular momentum that still fall into an extremal rotating black hole generate a flow along the curve of extremal solutions.
The generalization of charged AdS black hole specific volume and number density
Wang, Zi-Liang; He, Miao; Fang, Chao; Sun, Dao-Quan; Deng, Jian-Bo
2017-04-01
In this paper, by proposing a generalized specific volume, we restudy the P- V criticality of charged AdS black holes in the extended phase space. The results show that most of the previous conclusions can be generalized without change, but the ratio {\\tilde{ρ }}_c should be 3 {\\tilde{α }}/16 in general case. Further research on the thermodynamical phase transition of black hole leads us to a natural interpretation of our assumption, and more black hole properties can be generalized. Finally, we study the number density for charged AdS black hole in higher dimensions, the results show the necessity of our assumption.
Double-trace deformations and entanglement entropy in AdS
Miyagawa, Taiki; Shiba, Noburo; Takayanagi, Tadashi
2016-01-01
We compute the bulk entanglement entropy of a massive scalar field in a Poincare AdS with the Dirichlet and Neumann boundary condition when we trace out a half space. Moreover, by taking into account the quantum back reaction to the minimal surface area, we calculate how much the entanglement entropy changes under a double-trace deformation of a holographic CFT. In the AdS3/CFT2 setup, our result agrees with the known result in 2d CFTs. In higher dimensions, our results offer holographic predictions.
Double-trace deformations and entanglement entropy in AdS
Energy Technology Data Exchange (ETDEWEB)
Miyagawa, Taiki [Department of Physics, Kyoto University (Japan); Shiba, Noburo [Yukawa Institute for Theoretical Physics (YITP), Kyoto University (Japan); Takayanagi, Tadashi [Yukawa Institute for Theoretical Physics (YITP), Kyoto University (Japan); Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU), University of Tokyo, Kashiwa, Chiba (Japan)
2016-01-15
We compute the bulk entanglement entropy of a massive scalar field in a Poincare AdS with the Dirichlet and Neumann boundary condition when we trace out a half space. Moreover, by taking into account the quantum back reaction to the minimal surface area, we calculate how much the entanglement entropy changes under a double-trace deformation of a holographic CFT. In the AdS3/CFT2 setup, our result agrees with the known result in 2d CFTs. In higher dimensions, our results offer holographic predictions. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
Double-Trace Deformations and Entanglement Entropy in AdS
Miyagawa, Taiki; Takayanagi, Tadashi
2016-01-01
We compute the bulk entanglement entropy of a massive scalar field in a Poincare AdS with the Dirichlet and Neumann boundary condition when we trace out a half space. Moreover, by taking into account the quantum back reaction to the minimal surface area, we calculate how much the entanglement entropy changes under a double-trace deformation of a holographic CFT. In the AdS3/CFT2 setup, our result agrees with the known result in 2d CFTs. In higher dimensions, our results offer holographic predictions.
Aldazabal, G; Ibáñez, L E; Rabadan, Raul; Uranga, Angel M
2001-01-01
It is known that chiral fermions naturally appear at certain intersections of branes at angles. Motivated by this fact, we propose a string scenario in which different standard model gauge interactions propagate on different (intersecting) brane worlds, partially wrapped in the extra dimensions. Quarks and leptons live at brane intersections, and are thus located at different positions in the extra dimensions. Replication of families follows naturally from the fact that the branes generically intersect at several points. Gauge and Yukawa couplings can be computed in terms of the compactification radii. Hierarchical Yukawa couplings appear naturally, since amplitudes involving three different intersections are proportional to exp(-A_{ijk}), where A_{ijk} is the area of a string world-sheet extending among the intersections. The models are non-supersymmetric but the string scale may be lowered down to 1-10 TeV. The proton is however stable due to a set of discrete symmetries arising from world-sheet selection r...
Directory of Open Access Journals (Sweden)
Dr. Mohammed Viquaruddin
2012-11-01
Full Text Available This paper is an attempt regarding the general social/economical/ecological/political and more environments of world certainly with multidisciplinary/interdisciplinary approach. It is discussed that the problems of fore further can besolved through facts/reasoning/science/environment/social sciences etc. As beinga student of political science even peace science a try that can come into existenceor can be practiced only through many dimensions. The philosophy is developedto resist with whatever means we have in hand and are willing to fight for a betterscenario which would be something out of our reach! But can achieve through apositive and plural system not certainly perfect but different in its approach.Achievement to the threats and problems to the liberal vision are pervasive and thesystem is in much greater problematic that is commonly supposed. Protecting/Preserving/ Commanding it in the coming century and beyond will be easier saidthan done! We do not foresee the renaissance of any type we should be sure aboutthat alternative World Multidimensional System (WMS could reasonably competewith the present multidimensional system on theoretical or practical grounds. It isnot enough that this system display substantial practical advantages and genuinetheoretical coherence. No one can deny that world get profit from present system.
Niimi, R
1997-01-01
World leaders from 159 countries agreed at the 1990 World Summit for Children to specific goals which would reduce levels of child and maternal mortality, and give every child access to basic education, clean water, and proper sanitation by 2000. Major progress has since been achieved in most countries, with more than 80% of the world's children now immunized against diphtheria, tetanus, and pertussis. Moreover, the deaths of over 1 million children annually are being averted through the increased use of oral rehydration therapy against diarrheal dehydration, poliomyelitis and guinea worm have almost been eradicated, the consumption of iodized salt is protecting approximately 12 million infants annually from iodine deficiency, and access to safe drinking water is on the rise. Scientific developments in pediatrics, the strengthening of national health services, and the use of cost-effective primary health care approaches such as immunization, oral rehydration therapy, the promotion of breast feeding, and growth monitoring have helped reduce the national rate of infant mortality (IMR) in Turkey to 42 per 1000 live births compared to the urban IMR in Turkey during the 1940s of 300-350/1000. Developments in public health, the Convention on the Rights of the Child (CRC), education and child development, and child protection and the CRC are discussed.
β-secretase inhibitor; a promising novel therapeutic drug in AD
Directory of Open Access Journals (Sweden)
Kelly Willemijn Menting
2014-07-01
Full Text Available Alzheimer’s disease (AD and vascular dementia are responsible for up to 90% of dementia cases. According to the World Health Organization (WHO, a staggering number of 35.6 million people are currently diagnosed with dementia. Blocking disease progression or preventing AD altogether is desirable for both social and economic reasons and recently focus has shifted to a new and promising drug: the β-secretase inhibitor. Much of AD research has investigated the amyloid cascade hypothesis, which postulates that AD is caused by changes in amyloid beta (Aβ stability and aggregation. Blocking Aβ production by inhibiting the first protease required for its generation, β-secretase/BACE1, may be the next step in blocking AD progression. In April 2012, promising phase I data on inhibitor MK-8931 was presented. This drug reduced Aβ CSF levels up to 92% and was well tolerated by patients. In March 2013 data was added from a one week trial in 32 mild to moderate AD patients, showing CSF Aβ levels decreased up to 84%. However, BACE1 inhibitors require further research. First, greatly reducing Aβ levels through BACE1 inhibition may have harmful side effects. Second, BACE1 inhibitors have yet to pass clinical trial phase II/III and no data on possible side effects on AD patients are available. And third, there remains doubt about the clinical efficacy of BACE1 inhibitors. In moderate AD patients, Aβ plaques have already been formed. BACE1 inhibitors prevent production of new Aβ plaques, but hypothetically do not influence already existing Aβ peptides. Therefore, BACE1 inhibitors are potentially better at preventing AD instead of having therapeutic use.
The Stylistic Analysis of car ads languages
Institute of Scientific and Technical Information of China (English)
张伟苹
2014-01-01
Automotive advertising language is mix of phonetics, vocabulary, rhetoric, syntax, and discourse language etc., and owning a strong promotional effect which can functioned as a bridge between language expression and promotion system for es-sential products and consumers. As a kind of the commercial advertising, car advertising with its own unique language features not only for product considerably, but also enriches the advertising language. In order to analysis the car ads, this article draws at-tention from the aspects of the phonetics, vocabulary, rhetoric and syntax features, and aims to get a further and better analysis or understanding of the car ads Languages.
iAd Production Beginner's Guide
Collier, Ben
2012-01-01
This beginner's guide focuses on getting you through all the major learning points in a smooth, logical order. You'll also see how to avoid some common pitfalls. This book is for brands, advertisers and developers who want to create compelling, emotive, iAd advertisements that generate revenue and increase brand awareness. You don't need previous experience of creating adverts or apps for iPhone and iPad, as you'll be taken through the entire process to make motion-rich, beautiful ads.
Adding value to corporate ventures through governance
DEFF Research Database (Denmark)
Skat-Rørdam, Peter
2005-01-01
This working paper examines the governance of corporate ventures based upon a qualitative interview based case study of a European industrial conglomerate. The purpose is to explore the value adding mechanisms of governance, that are considered more critical to the success of corporate ventures...... than the control mechanisms widely explored in connection with the governance of large public corporations. The paper provides examples of how value can be added as well as perspectives on the challenges and effectivenes here-off as evaluated by venture CEO's and venture board members...
Intermittently connected mobile ad hoc networks
Jamalipour, Abbas
2011-01-01
In the last few years, there has been extensive research activity in the emerging area of Intermittently Connected Mobile Ad Hoc Networks (ICMANs). By considering the nature of intermittent connectivity in most real word mobile environments without any restrictions placed on users' behavior, ICMANs are eventually formed without any assumption with regard to the existence of a end-to-end path between two nodes wishing to communicate. It is different from the conventional Mobile Ad Hoc Networks (MANETs), which have been implicitly viewed as a connected graph with established complete paths betwe
Vehicular ad hoc network security and privacy
Lin, X
2015-01-01
Unlike any other book in this area, this book provides innovative solutions to security issues, making this book a must read for anyone working with or studying security measures. Vehicular Ad Hoc Network Security and Privacy mainly focuses on security and privacy issues related to vehicular communication systems. It begins with a comprehensive introduction to vehicular ad hoc network and its unique security threats and privacy concerns and then illustrates how to address those challenges in highly dynamic and large size wireless network environments from multiple perspectives. This book is richly illustrated with detailed designs and results for approaching security and privacy threats.
Ad hoc networks telecommunications and game theory
Benslama, Malek; Batatia, Hadj
2015-01-01
Random SALOHA and CSMA protocols that are used to access MAC in ad hoc networks are very small compared to the multiple and spontaneous use of the transmission channel. So they have low immunity to the problems of packet collisions. Indeed, the transmission time is the critical factor in the operation of such networks. The simulations demonstrate the positive impact of erasure codes on the throughput of the transmission in ad hoc networks. However, the network still suffers from the intermittency and volatility of its efficiency throughout its operation, and it switches quickly to the satura
World Standards Day and Its Contribution to the World
Institute of Scientific and Technical Information of China (English)
2011-01-01
The World Standards Day began in 1970.From 1986,ISO President started to deliver a speech to the world onthe World Standards Day.From 1988,IEC President and ISO President jointly delivered the speech for the World Standards Day.From 1993,the ITU SecretaryGeneral also joined them for the speech on World Standards Day.The 3 most influential international standardization organizations have jointly promoted the World Standards Day,and the theme of every year's speech clearly suggests the development course and trend of standardization.
Preferential survival in models of complex ad hoc networks
Kong, Joseph S.; Roychowdhury, Vwani P.
2008-05-01
There has been a rich interplay in recent years between (i) empirical investigations of real-world dynamic networks, (ii) analytical modeling of the microscopic mechanisms that drive the emergence of such networks, and (iii) harnessing of these mechanisms to either manipulate existing networks, or engineer new networks for specific tasks. We continue in this vein, and study the deletion phenomenon in the web by the following two different sets of websites (each comprising more than 150,000 pages) over a one-year period. Empirical data show that there is a significant deletion component in the underlying web networks, but the deletion process is not uniform. This motivates us to introduce a new mechanism of preferential survival (PS), where nodes are removed according to the degree-dependent deletion kernel, D(k)∝k, with α≥0. We use the mean-field rate equation approach to study a general dynamic model driven by Preferential Attachment (PA), Double PA (DPA), and a tunable PS (i.e., with any α>0), where c nodes ( cdynamics reported in this work can be used to design and engineer stable ad hoc networks and explain the stability of the power-law exponents observed in real-world networks.
Directory of Open Access Journals (Sweden)
Ayman G. Abdel Tawab
2014-09-01
Full Text Available New Gourna Village, which is located inside one of the World Heritage Sites in Egypt, has never been recognized as an element contributing to the site’s Outstanding Universal Value. The recognition of the village as a contributing element is reliant on the successful assessment of its authenticity and integrity. Responding to the dramatically declining integrity of the village, the World Heritage Centre has carried out an architectural study to guide the potential conservation works in the property. The study has recommended that a group of objectives and two approaches to the conservation of the village should be adopted. One of these two approaches has been concerned with the conservation of the village according to the architect’s original intentions and principles. The previous approach can be called the principles-based approach. The main aim of this study was to examine the agreement of the World Heritage Centre’s objectives and their proposed principles-based approach to the conservation of the village with the aim to improve its chance in meeting the conditions of authenticity and integrity. The study approached the previous aim by assessing, by means of a proposed methodology; the level of significance, authenticity and integrity of the property. Based on the previous assessment, a list of conservation interventions was proposed to improve the property’s chance in meeting the conditions of authenticity and integrity. Finally, the World Heritage Centre’s recommended approaches and objectives were examined against the previous proposed conservation interventions. The findings indicated the possibility to adopt the principles-based approach to the conservation of New Gourna Village, as well as the other World Heritage Centre’s objectives, without limiting the property’s chance in meeting the conditions of authenticity and integrity. The study recommends to carry out further studies that are concerned with the identification
Bibliography: Current world literature.
2009-07-01
This bibliography is compiled by clinicians from the journals listed at the end of this publication. It is based on literature entered into our database between 1 March 2008 and 28 February 2009 (articles are generally added to the database about two and a half months after publication). In addition, the bibliography contains every paper annotated by reviewers; these references were obtained from a variety of bibliographic databases and published between the beginning of the review period and the time of going to press. The bibliography has been grouped into topics that relate to the reviews in this issue.
Bibliography. Current world literature.
2009-07-01
This bibliography is compiled by clinicians from the journals listed at the end of this publication. It is based on literature entered into our database between 1 March 2008 and 28 February 2009 (articles are generally added to the database about two and a half months after publication). In addition, the bibliography contains every paper annotated by reviewers; these references were obtained from a variety of bibliographic databases and published between the beginning of the review period and the time of going to press. The bibliography has been grouped into topics that relate to the reviews in this issue.
q-Deformation of the AdS5 x S5 Superstring S-matrix and its Relativistic Limit
Hoare, Ben; Miramontes, J Luis
2011-01-01
A set of four factorizable non-relativistic S-matrices for a multiplet of fundamental particles are defined based on the R-matrix of the quantum group deformation of the centrally extended superalgebra su(2|2). The S-matrices are a function of two independent couplings g and q=exp(i\\pi/k). The main result is to find the scalar factor, or dressing phase, which ensures that the unitarity and crossing equations are satisfied. For generic (g,k), the S-matrices are branched functions on a product of rapidity tori. In the limit k->infinity, one of them is identified with the S-matrix describing the magnon excitations on the string world sheet in AdS5 x S5, while another is the mirror S-matrix that is needed for the TBA. In the g->infinity limit, the rapidity torus degenerates, the branch points disappear and the S-matrices become meromorphic functions, as required by relativistic S-matrix theory. However, it is only the mirror S-matrix which satisfies the correct relativistic crossing equation. The mirror S-matrix ...
ENEA presenta sistema ADS per trattamento scorie
2002-01-01
"Arriva il sistema Ads (Accelerator driven system) per il trattamento dei rifiuti radioattivi. Lo studio di fattibilita' per l' innovativa tecnologia, realizzato da un gruppo di lavoro congiunto Enea, Cea, Cern e Ansaldo, e' stato presentato oggi nel corso di un workshop presieduto dal premio Nobel per la fisica, Carlo Rubbia" (1/2 page).
Value-Added Modeling in Physical Education
Hushman, Glenn; Hushman, Carolyn
2015-01-01
The educational reform movement in the United States has resulted in a variety of states moving toward a system of value-added modeling (VAM) to measure a teacher's contribution to student achievement. Recently, many states have begun using VAM scores as part of a larger system to evaluate teacher performance. In the past decade, only "core…
Navy Additive Manufacturing: Adding Parts, Subtracting Steps
2015-06-01
NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA MBA PROFESSIONAL REPORT NAVY ADDITIVE MANUFACTURING : ADDING PARTS, SUBTRACTING...blank) 2. REPORT DATE June 2015 3. REPORT TYPE AND DATES COVERED MBA Professional Report 4. TITLE AND SUBTITLE NAVY ADDITIVE MANUFACTURING ...DISTRIBUTION CODE 13. ABSTRACT (maximum 200 words) This study examines additive manufacturing (AM) and describes its potential impact on the Navy’s Supply
Added value: The differences that count
Directory of Open Access Journals (Sweden)
Dominique Bouchet
2012-08-01
Full Text Available Clinging to a simplistic conceptualization of the concept of added value might impair our capability to develop insights to what really matters today when companies seek to make differences within the global market. Today it is more necessary than ever to take into account the importance of language and culture as competitive factors.
Test Scaling and Value-Added Measurement
Ballou, Dale
2009-01-01
Conventional value-added assessment requires that achievement be reported on an interval scale. While many metrics do not have this property, application of item response theory (IRT) is said to produce interval scales. However, it is difficult to confirm that the requisite conditions are met. Even when they are, the properties of the data that…
The Added Value of Business Models
Vliet, Harry van
2014-01-01
An overview of innovations in a particular area, for example retail developments in the fashion sector (Van Vliet, 2014), and a subsequent discussion about the probability as to whether these innovations will realise a ‘breakthrough’, has to be supplemented with the question of what the added value
CERN Enters the Second Year AD
2001-01-01
2001 is the year that physics at CERN's new Antiproton Decelerator (AD) really gets up to speed. Changes to the AD since 2000 mean that this year the three experiments, ASACUSA, ATHENA, and ATRAP have had more intense antiproton beams to work with since physics started on 7 May. CERN's Antiproton Decelerator - major improvements for 2001. The AD is a unique machine. Its job is to decelerate not accelerate particle beams, and it has to handle beam energies that vary by an unprecedented factor of 35 from injection to ejection. Since the machine was designed to operate at fixed energy in its first incarnation as a collector of antiprotons for CERN's 1980s proton antiproton collider, this factor of 35 presented a big challenge to the AD team. The team's design goal was to hang onto a quarter of the injected antiprotons through their vertiginous fall in energy, and to repeat the deceleration cycle once per minute. Improvements to the machine over the winter shutdown and through the first four weeks of 2001 run...
de Leeuw, Marius; Moriyama, Sanefumi; Regelskis, Vidas; Torrielli, Alessandro
2012-01-01
We discuss special quantum group (secret) symmetries of the integrable system associated to the AdS/CFT correspondence. These symmetries have by now been observed in a variety of forms, including the spectral problem, the boundary scattering problem, n-point amplitudes, the pure-spinor formulation and quantum affine deformations.
Adding calcium improves lithium ferrite core
Lessoff, H.
1969-01-01
Adding calcium increases uniformity of grain growth over a wide range of sintering temperatures and reduces porosity within the grain. Ferrite cores containing calcium have square hysteresis loops and high curie temperatures, making them useful in coincident current memories of digital electronic computers.
Adding Users to the Website Design Process
Tomeo, Megan L.
2012-01-01
Alden Library began redesigning its website over a year ago. Throughout the redesign process the students, faculty, and staff that make up the user base were added to the conversation by utilizing several usability test methods. This article focuses on the usability testing conducted at Alden Library and delves into future usability testing, which…
Context discovery in ad-hoc networks
Liu, Fei
2011-01-01
Mobile ad-hoc networks (MANETs) are more and more present in our daily life. Such networks are often composed of mobile and battery-supplied devices, like laptops and PDAs. With no requirement for infrastructure support, MANETs can be used as temporary networks, such as for conference and office env
Integrable strings for AdS/CFT
Borsato, R.
2015-01-01
In this thesis we discuss certain models that arise in string theory, motivated by the AdS/CFT correspondence. For these models there exists a notion of “quantum Integrability”. Although this term is very broad, for us it will be used in the sense of factorisation of scattering for models in 1+1 dim
Holzscheiter, M H
2014-01-01
After 7 years running the AD-4 Experiment at antiproton momentum of 502 MeV/c we have now assembled a complete data set and are preparing to combine all years into a single analysis of RBE vs. Depth for an antiproton beam stopping in water. We describe experimental challenges and computational issues which need to be resolved to achieve this final step.
Double Thermalization via AdS/CFT
Ali-Akbari, M; Kishani-Farahani, A; Shafie, N
2016-01-01
We exploit the AdS/CFT correspondence to investigate thermalization in an N=2 strongly coupled gauge theory including massless fundamental matter (quark). More precisely, we consider the response of a zero temperature state of the gauge theory under variation of an external electric field leading to a time-dependent current. The holographic dual of the above set-up is given by introducing a time-dependent electric field on the probe D7-brane embedded in an AdS_5 X S^5 background. In the dual gravity theory, due to a time-dependent electric field an apparent horizon forms on the brane which, according to AdS/CFT dictionary, is the counterpart of the thermalization process in the gauge theory. We classify different functions for time-dependent electric field and study their effect on the apparent horizon formation. In the case of pulse functions where the electric field varies from zero to zero, apart from non-equilibrium phase, we observe that two apparent horizons form on the brane. On the gauge theory side, ...
Foundations of the AdS{sub 5} x S{sup 5} superstring: I
Energy Technology Data Exchange (ETDEWEB)
Arutyunov, Gleb [Institute for Theoretical Physics and Spinoza Institute, Utrecht University, 3508 TD Utrecht (Netherlands); Frolov, Sergey [Hamilton Mathematics Institute and School of Mathematics, Trinity College, Dublin 2 (Ireland)], E-mail: G.E.Arutyunov@uu.nl, E-mail: frolovs@maths.tcd.ie
2009-06-26
We review the recent advances towards finding the spectrum of the AdS{sub 5} x S{sup 5} superstring. We thoroughly explain the theoretical techniques which should be useful for the ultimate solution of the spectral problem. In certain cases our exposition is original and cannot be found in the existing literature. The present part I deals with foundations of classical string theory in AdS{sub 5} x S{sup 5}, light-cone perturbative quantization and the derivation of the exact light-cone world-sheet scattering matrix.
Geometry and supersymmetry of heterotic warped flux AdS backgrounds
Beck, S.; Gutowski, J.; Papadopoulos, G.
2015-07-01
We classify the geometries of the most general warped, flux AdS backgrounds of heterotic supergravity up to two loop order in sigma model perturbation theory. We show under some mild assumptions that there are no AdS n backgrounds with n ≠ 3. Moreover the warp factor of AdS3 backgrounds is constant, the geometry is a product AdS 3 × M 7 and such solutions preserve, 2, 4, 6 and 8 supersymmetries. The geometry of M 7 has been specified in all cases. For 2 supersymmetries, it has been found that M 7 admits a suitably restricted G 2 structure. For 4 supersymmetries, M 7 has an SU(3) structure and can be described locally as a circle fibration over a 6-dimensional KT manifold. For 6 and 8 supersymmetries, M 7 has an SU(2) structure and can be described locally as a S 3 fibration over a 4-dimensional manifold which either has an anti-self dual Weyl tensor or a hyper-Kähler structure, respectively. We also demonstrate a new Lichnerowicz type theorem in the presence of α' corrections.
On Critical Massive (Super)Gravity in adS(3)
Bergshoeff, Eric A.; Hohm, Olaf; Rosseel, Jan; Sezgin, Ergin; Townsend, Paul K.; Aldaya,; Barcelo, C; Jaramillo, JL
2011-01-01
We review the status of three-dimensional "general massive gravity" (GMG) in its linearization about an anti-de Sitter (adS) vacuum, focusing on critical points in parameter space that yield generalizations of "chiral gravity". We then show how these results extend to,N = 1 super-GMG, expanded about
Correction terms to Newton law due to induced gravity in AdS background
Ito, M
2003-01-01
We calculate small correction terms to gravitational potential on Randall-Sundrum brane with an induced Einstein term. The behaviors of the correction terms depend on the magnitudes of $AdS$ radius $k^{-1}$ and a characteristic length scale $\\l$ of model. We present the gravitational potential for arbitrary $k$ and $\\l$ at all distances.
The Complexity of Identifying Ryu-Takayanagi Surfaces in AdS3/CFT2
Bao, Ning
2016-01-01
We present a constructive algorithm for the determination of Ryu-Takayanagi surfaces in AdS3/CFT2 which exploits previously noted connections between holographic entanglement entropy and max-flow/min-cut. We then characterize its complexity as a polynomial time algorithm.
String hypothesis for the AdS5 × S5 mirror
Arutyunov, G.E.; Frolov, S.
2009-01-01
We discuss the states which contribute in the thermodynamic limit of the mirror theory, the latter is obtained from the light-cone gauge-fixed string theory in the AdS_5 x S^5 background by the double-Wick rotation. We analyze the Bethe-Yang equations for the mirror theory and formulate the string h
Entanglement Entropy and Higher Spin Holography in AdS3
de Boer, J.; Jottar, J.I.
2014-01-01
A holographic correspondence has been recently developed between higher spin theories in three-dimensional anti-de Sitter space (AdS3) and two-dimensional Conformal Field Theories (CFTs) with extended symmetries. A class of such dualities involves SL(N, R) × SL(N, R) Chern-Simons gauge theories in t
Searching for AdS_3 waves and Asymptotically Lifshitz black holes in R^3-NMG
Anastasiou, Giorgos G; Vagenas, Elias C
2013-01-01
In this paper we consider the structure of the $AdS_3$ vacua in $R^3$ expansion of the New Massive Gravity ($R^3$-NMG). We obtain the degeneracies of the $AdS_3$ vacua at several points of the parametric space. Additionally, following a specific analysis we show that $AdS_3$ wave solutions are present. Using these wave solutions, we single out two special points of the parametric space for which logarithmic terms appear in the solutions. The first one is a point at which the effective mass of the wave profile which is interpreted as a scalar mode, completely saturates the Breitenlohner-Freedman bound of the $AdS_3$ space in which the wave is propagating. The second special point is a point at which the central charge of the theory vanishes. Furthermore, we investigate the possibility of asymptotically Lifshitz black solutions to be present in the three-dimensional $R^3$-NMG. We derive analytically the Lifshitz vacua considering specific relations between the mass parameters of $R^3$-NMG. A certain polynomial ...
Near horizon data and physical charges of extremal AdS black holes
Astefanesei, D.; Banerjee, N.; Dutta, S.
2011-01-01
We compute the physical charges and discuss the properties of a large class of five-dimensional extremal AdS black holes by using the near horizon data. Our examples include baryonic and electromagnetic black branes, as well as supersymmetric spinning black holes. In the presence of the gauge Chern–
Ad Hoc Network Security Technology%Ad hoc网络安全技术简介
Institute of Scientific and Technical Information of China (English)
李俊; 李鑫; 黄红伟
2011-01-01
Ad hoc network is a kind of mobile network without fixed infrastructure;all nodes are composed of mobile host.As the mobility of the node leads to network topology changing quickly and node communication is based on wireless links,Ad hoc network is facing greater challenges more than cane network about security.In this paper,according to Ad hoe network security issues,we analysis common attacks in the Ad hoe network,focused on secure routing,key management and other key issues.%Ad hoc网络是一种没有有线基础设施支持的移动网络，网络中的节点均由移动主机构成。由于节点的移动性导致网络拓扑结构不断变化，节点通信完全依靠无线链路，相对于有线网络在安全性上面临更大的挑战。本文根据Ad hoc网络面临的安全问题，分析了Ad hoc网络中常见的攻击方式，并集中讨论了Ad hoc网络的安全路由、密钥管理等关键问题。
D-branes from Pure Spinor Superstring in AdS_5 x S^5 Background
Hanazawa, Sota
2016-01-01
We examine the surface term for the BRST transformation of the open pure spinor superstring in an AdS_5 x S^5 background. We find that the boundary condition to eliminate the surface term leads to a classification of possible configurations of 1/2 supersymmetric D-branes.
F-string Solution in AdS4 X CP3 PP-wave Background
Banerjee, Gourav
2016-01-01
We present supergravity solution for F-string in pp wave background obtained from AdS4 X CP3 with zero flat directions.The classical solution is shown to break all space-time supersymmetries. We explicitly write down the standard as well as supernumerary Killing spinors both for the background and F-string solution.
Phase transitions of magnetic AdS4 black holes with scalar hair
Hristov, K.; Toldo, C.; Vandoren, S.
2013-01-01
We determine the thermodynamic properties of a class of spherically symmetric and static black holes in AdS4 with magnetic charges and scalar hair. These black holes are solutions in four-dimensional N=2 gauged supergravity that can arise from 11-dimensional supergravity compactified on S7. At zero
The $AdS_{5}xS^(5)$ fermionic model
Abdalla, Elcio
2013-01-01
We consider the $AdS_{5}xS^(5)$ integrable model. As it turns out, relying on well known arguments, we claim that the conformally invariant fermionic model is solvable, the resulting solution given in terms of two current algebras realizations.
Magnetic charges in the AdS(4) superalgebra osp(4 vertical bar 2)
Dibitetto, Giuseppe; Klemm, Dietmar
2010-01-01
We discuss the issue of how to include magnetic charges in the AdS(4) superalgebra osp(4 vertical bar 2). It is shown that the usual way of introducing a pseudoscalar central charge on the right hand side of the basic anticommutator does not work, because this breaks SO(2, 3) covariance. We propose
EVH Black Holes, AdS3 Throats and EVH/CFT Proposal
Sheikh-Jabbaria, M M
2011-01-01
Within class of generic black holes there are extremal black holes (with vanishing Hawking temperature T) and vanishing horizon area Ah, but with finite Ah/T ratio,the Extremal Vanishing Horizon (EVH) black holes. We study the near horizon limit of a four dimensional EVH black hole solution to a generic (gauged) Einstein-Maxwell dilaton theory and show that in the near horizon limit they develop a throat which is a pinching orbifold limit of AdS3. This is an extension of the well known result for extremal black holes the near horizon limit of which contains an AdS2 throat. We show that in the near EVH near horizon limit the pinching AdS3 factor turns to a pinching BTZ black hole and that this near horizon limit is indeed a decoupling limit. We argue that the pinching AdS3 or BTZ orbifold is resolved if the near horizon limit is accompanied by taking the 4d Newton constant G4 to zero such that the Bekenstein-Hawking entropy S = Ah/(4G4) remains finite. We propose that in this limit the near horizon EVH black h...
Jordanian deformations of the AdS5×S5 superstring
Kawaguchi, I.; Matsumoto, T.; Yoshida, K
2014-01-01
We consider Jordanian deformations of the AdS_5xS^5 superstring action. The deformations correspond to non-standard q-deformation. In particular, it is possible to perform partial deformations, for example, only for the S^5 part. Then the classical action and the Lax pair are constructed with a line
The spectral problem for strings on twisted AdS5 ×S5
de Leeuw, M.; van Tongeren, S.J.
2012-01-01
We discuss the spectral problem for integrable superstrings on generically twisted AdS5 × S5, meaning all its orbifolds and TsT transformed versions. We explicitly give the asymptotic description of these theories through a twisted transfer matrix, and carefully match the geometric deformations with
Simplified TBA equations of the AdS5 × S5 mirror model
Arutyunov, G.E.; Frolov, S.
2009-01-01
We use the recently found integral representation for the dressing phase in the kinematic region of the mirror theory to simplify the TBA equations for the AdS5 × S5 mirror model. The resulting set of equations provides an efficient starting point for both analytic and numerical studies.
Bound state transfer matrix for AdS5 × S5 superstring
Arutyunov, G.E.; de Leeuw, M.; Suzuki, R.; Torrielli, A.
2009-01-01
We apply the algebraic Bethe ansatz technique to compute the eigenvalues of the transfer matrix constructed from the general bound state S-matrix of the light-cone AdS5 × S5 superstring. This allows us to verify certain conjectures on the quantum characteristic function, and to extend them to the ge
The S-matrix of the AdS5xS5 superstring
de Leeuw, M.
2010-01-01
According to the gauge-string duality conjecture, the spectrum of scaling dimensions of composite gauge invariant operators of the planar maximally supersymmetric Yang-Mills theory in four dimensions should be equivalent to the energy spectrum of superstrings propagating in the AdS5 x S5 space-time,
D-branes from pure spinor superstring in AdS5 × S5 background
Hanazawa, Sota; Sakaguchi, Makoto
2017-01-01
We examine the surface term for the BRST transformation of the open pure spinor superstring in an AdS5 ×S5 background. We find that the boundary condition to eliminate the surface term leads to a classification of possible configurations of 1/2 supersymmetric D-branes.
The bound state S-matrix for AdS5×S5 superstring
Arutyunov, G.E.; de Leeuw, M.; Torrielli, A.
2009-01-01
We determine the S-matrix that describes scattering of arbitrary bound states in the light-cone string theory in AdS5×S5. The corresponding construction relies on the Yangian symmetry and the superspace formalism for the bound state representations. The basic analytic structure supporting the S-matr
Classical strings in $AdS_4\\times\\mathbb{CP}^3$ with three angular momenta
Giardino, Sergio
2011-01-01
In this paper, rotating strings in three directions of $AdS_4 \\times \\mathbb{CP}^3$ geometry are studied; its divergent energy limit, and conserved charges are also determined. An interpretation of these configurations as either giant magnons or spiky strings are discussed.
Parametrization of cosets for AdS5xS5 superstring action
Siegel, W
2015-01-01
A formulation recently proposed [arXiv:1506.07706] as an alternative to the usual coset PSU(2,2|4)/USp(2,2)USp(4) for the superspace geometry of the Type IIB superstring on an AdS5xS5 background is shown to be a particular parametrization of this coset. Standard methods can then be applied.
Finite temperature effective action, AdS_5 black holes, and 1/N expansion
Alvarez-Gaumé, Luís; Liu, H; Wadia, S; Alvarez-Gaume, Luis; Gomez, Cesar; Liu, Hong; Wadia, Spenta
2005-01-01
We propose a phenomenological matrix model to study string theory in AdS_5 \\times S_5 in the canonical ensemble. The model reproduces all the known qualitative features of the theory. In particular, it gives a simple effective potential description of Euclidean black hole nucleation and the tunnelling between thermal AdS and the big black hole. It also has some interesting predictions. We find that there exists a critical temperature at which the Euclidean small black hole undergoes a Gross-Witten phase transition. We identify the phase transition with the Horowitz-Polchinski point where the black hole horizon size becomes comparable to the string scale. The appearance of the Hagedorn divergence of thermal AdS is due to the merger of saddle points corresponding to the Euclidean small black hole and thermal AdS. The merger can be described in terms of a cusp (A_3) catastrophe and divergences at the perturbative string level are smoothed out at finite string coupling using standard techniques of catastrophe the...
An alternative perspective to observe the critical phenomena of dilaton AdS black holes
Mo, Jie-Xiong
2016-01-01
The critical phenomena of dilaton AdS black holes are probed from a totally different perspective other than the $P-v$ criticality and the $q-U$ criticality discussed in the former literature. We investigate not only the two point correlation function but also the entanglement entropy of dilaton AdS black holes. We achieve this goal by solving the equation of motion constrained by the boundary condition numerically and we concentrate on $\\delta L$ and $\\delta S$ which have been regularized by subtracting the terms in pure AdS with the same boundary region. For both the two point correlation function and the entanglement entropy, we consider $4\\times2\\times2=16$ cases due to different choices of parameters. The van der Waals like behavior can be clearly witnessed from all the $T-\\delta L$ ($T-\\delta S$) graphs for $q
Supersymmetric $AdS_6$ vacua in six-dimensional $N=(1,1)$ gauged supergravity
Karndumri, Parinya
2016-01-01
We study fully supersymmetric $AdS_6$ vacua of half-maxi\\-mal $N=(1,1)$ gauged supergravity in six space-time dimensions coupled to $n$ vector multiplets. We show that the existence of $AdS_6$ backgrounds requires that the gauge group is of the form $G'\\times G"\\subset SO(4,n)$ where $G'\\subset SO(3,m)$ and $G"\\subset SO(1,n-m)$. In the $AdS_6$ vacua this gauge group is broken to its maximal compact subgroup $SO(3)\\times H'\\times H"$ where $H'\\subset SO(m)$ and $H"\\subset SO(n-m)$. Furthermore, the $SO(3)$ factor is the R-symmetry gauged by three of the four graviphotons. We further show that the $AdS_6$ vacua have no moduli that preserve all supercharges. This is precisely in agreement with the absence of supersymmetric marginal deformations in holographically dual five-dimensional superconformal field theories.
Designing added functions in engineered cementitious composites
Yang, En-Hua
In this dissertation, a new and systematic material design approach is developed for ECC with added functions through material microstructures linkage to composite macroscopic behavior. The thesis research embodies theoretical development by building on previous ECC micromechanical models, and experimental investigations into three specific new versions of ECC with added functions aimed at addressing societal demands of our built infrastructure. Specifically, the theoretical study includes three important ECC modeling elements: Steady-state crack propagation analyses and simulation, predictive accuracy of the fiber bridging constitutive model, and development of the rate-dependent strain-hardening criteria. The first element establishes the steady-state cracking criterion as a fundamental requirement for multiple cracking behavior in brittle matrix composites. The second element improves the accuracy of crack-width prediction in ECC. The third element establishes the micromechanics basis for impact-resistant ECC design. Three new ECCs with added functions were developed and experimentally verified in this thesis research through the enhanced theoretical framework. A green ECC incorporating a large volume of industrial waste was demonstrated to possess reduced crack width and drying shrinkage. The self-healing ECC designed with tight crack width was demonstrated to recover transport and mechanical properties after microcrack damage when exposed to wet and dry cycles. The impact-resistant ECC was demonstrated to retain tensile ductility with increased strength under moderately high strain-rate loading. These new versions of ECC with added functions are expected to contribute greatly to enhancing the sustainability, durability, and safety of civil infrastructure built with ECC. This research establishes the effectiveness of micromechanics-based design and material ingredient tailoring for ECC with added new attributes but without losing its basic tensile ductile
World Bioenergy 2012. Proceedings
Energy Technology Data Exchange (ETDEWEB)
NONE
2012-11-01
The conference of 2012 had contributions on the following themes: A: World Pellets 2012, B: Market outlook, C: Energy systems, D: Transportation, E: World biorefinery 2012, F: Sustainable bioenergy day. 52 contributions in A - D. A: World Pellets 2012 is an integrated part of World Bioenergy 2012. A three day 'conference in the conference' covering all aspects of pellets: raw material potentials, innovative pellets production systems, torrefaction, new combustion technologies, trade and market development, health and safety aspects, etc. B) Market outlook: Policy and targets for renewable energy to find an alternative to fossil energy are being put in place, increasing the demand for sustainable modern bioenergy. Global trade and improved logistics open up to the markets. To facilitate international trade in bioenergy commodities, new trading places and indexes are needed, as well as generally accepted standards. Supply and demand must meet to guarantee stable prices. In this session you learn all about current market development, including drivers like incentives and policies. C) Energy Systems: Modern bioenergy is a young industry. Therefore, technical development is rapid, with many new innovations. This session focuses on technical development in the whole bioenergy chain, from harvesting of forest residues to combustion technologies and co-firing. Optimal use of biomass through district heating or cooling - small scale and large scale - and CHP technology for electricity production. D) Transportation: Sustainable transports are one of the key challenges of tomorrow. Can we transport biomass as well as other products sustainably and at what costs? Which are the future fuels for transports and when will biofuels be viewed as profitable? Biofuels for transport are under rapid development with new methods, producers and feedstock entering the markets. The future biofuels will be produced in biorefineries, to increase profitability and optimize feed
Grid Added Value to Address Malaria
Breton, V; Hofmann, M
2008-01-01
Through this paper, we call for a distributed, internet-based collaboration to address one of the worst plagues of our present world, malaria. The spirit is a non-proprietary peer-production of information-embedding goods. And we propose to use the grid technology to enable such a world wide "open source" like collaboration. The first step towards this vision has been achieved during the summer on the EGEE grid infrastructure where 46 million ligands were docked for a total amount of 80 CPU years in 6 weeks in the quest for new drugs.
Antiretrovirals for developing world.
Adler, M W
1998-01-24
The most recent UNAIDS figures indicate that approximately 30 million people are infected with HIV worldwide, 5.8 million of whom were newly infected during 1997. At the 10th International Conference on AIDS and Sexually Transmitted Diseases in Africa, the President and Secretary of Health of France called upon developed countries to establish a Therapeutic Assistance Fund to make antiretrovirals available to people with HIV/AIDS in sub-Saharan Africa. While the annual per capita health budget in most African countries is less than US$10, triple antiretroviral therapy against AIDS in the developed world costs $12,000-14,000 per patient per year. Calculations based upon a lower per patient cost of $7000, and treating all 1.4 million African AIDS cases, would cost US$10 billion per year for drugs alone, more than 30 times the amount currently spent annually by international donors for AIDS programs in the entire developing world. Basic infrastructural requirements would have to be met were antiretrovirals made widely available, ranging from HIV screening and counseling to the provision of clean water with which to consume the required 20-30 tablets per day. High program costs will challenge long-term sustainability. Universal access to care and treatment for HIV infection and AIDS is not a reality in the developed world, let alone feasible in developing countries. Given the competing health care priorities in developing countries, the high costs of antiretroviral agents, poor infrastructure, and inability to sustain such a program, the French initiative is ill-advised and foolish public health practice.
Hairy Black Holes in AdS$_5\\times S^5$
Markeviciute, J
2016-01-01
We use numerical methods to exhaustively study a novel family of hairy black hole solutions in AdS$_5$. These solutions can be uplifted to solutions of type IIB supergravity with AdS$_5\\times S^5$ asymptotics and are thus expected to play an important role in our understanding of AdS/CFT. We find an intricate phase diagram, with the aforementioned family of hairy black hole solutions branching from the Reissner-Nordstr\\"om black hole at the onset of the superradiance instability. We analyse black holes with spherical and planar horizon topology and explain how they connect in the phase diagram. Finally, we detail their global and local thermodynamic stability across several ensembles.
Black Hole Formation in AdS Einstein-Gauss-Bonnet Gravity
Deppe, Nils; Frey, Andrew R; Kunstatter, Gabor
2016-01-01
AdS spacetime has been shown numerically to be unstable against a large class of arbitrarily small perturbations. In arXiv:1410.1869, the authors presented a preliminary study of the effects on stability of changing the local dynamics by adding a Gauss-Bonnet term to the Einstein action. Here we provide further details as well as new results with improved numerical methods. In particular, we elucidate new structure in Choptuik scaling plots. We also provide evidence of chaotic behavior at the transition between immediate horizon formation and horizon formation after the matter pulse reflects from the AdS conformal boundary. Finally, we present data suggesting the formation of naked singularities in spacetimes with ADM mass below the algebraic bound for black hole formation.
Holographic Thermalization, Stability of AdS, and the FPU Paradox
Balasubramanian, Venkat; Green, Stephen R; Lehner, Luis; Liebling, Steven L
2014-01-01
For a real massless scalar field in general relativity with a negative cosmological constant, we uncover a large class of spherically symmetric initial conditions that are close to AdS, but whose numerical evolution does not result in black hole formation. According to the AdS/CFT dictionary, these bulk solutions are dual to states of a strongly interacting boundary CFT that fail to thermalize at late times. Furthermore, as these states are not stationary, they define dynamical CFT configurations that do not equilibrate. We develop a two-timescale perturbative formalism that captures both direct and inverse cascades of energy and agrees with our fully nonlinear evolutions in the appropriate regime. We also show that this formalism admits a large class of quasi-periodic solutions. Finally, we demonstrate a striking parallel between the dynamics of AdS and the classic Fermi-Pasta-Ulam-Tsingou problem.
2012-01-01
In the last year of the first decade of the 21st century, in the verge of breaking into the era of digital television, it is important to know what kind of television model is available in Portugal. The analysis of the news coverage of the FIFA 2010 World Cup will certainly help in finding the answers. In this article, we present a study that centers its focus on news formats related to this great media event, broadcasted in both generalist as well as cable news networks between the 11th of J...
Energy Technology Data Exchange (ETDEWEB)
NONE
2010-07-01
The IEA produced its first handy, pocket-sized summary of key energy data in 1997. This new edition responds to the enormously positive reaction to the book since then. Key World Energy Statistics produced by the IEA contains timely, clearly-presented data on supply, transformation and consumption of all major energy sources. The interested businessman, journalist or student will have at his or her fingertips the annual Canadian production of coal, the electricity consumption in Thailand, the price of diesel oil in Spain and thousands of other useful energy facts. It exists in different formats to suit our readers' requirements.
Naturally Connecting the World
Institute of Scientific and Technical Information of China (English)
2010-01-01
@@ During China International Trade Fair for Home Textiles and Accessories held in Shanghai 2010(on Aug.25th the second day of the fair),Cotton Council International(CCI)hosted an exchange meeting targeted the COTTON USATM home textile licenses,taking"Naturally Connecting the World-Opportunities for Sourcing and Collaboration with Cotton-Made Home Textiles"as the theme of the meeting.CCI's representative institution in China invited the domestic famous home textile brands,enterprises and their customers to participate in the exchange which aims to introduce the current development trend of the global cotton textile industry through CCI,the powerful platform of communication.
Moon, S H
2001-01-01
We consider a brane world residing in the interior region inside the horizon of extreme black branes. In this picture, the size of the horizon can be interpreted as the compactification size. The large mass hierarchy is simply translated into the large horizon size, which is provided by the magnitude of charges carried by the black branes. Hence, the macroscopic compactification size is a quantity calculable from the microscopic theory which has only one physical scale, and its stabilization is guaranteed from the charge conservation.
Institute of Scientific and Technical Information of China (English)
JIANG WANDI
2010-01-01
@@ Ballet, the dance created for court performances in Renaissance Europe that reached into the world of high art in early 17th century France, has long been loved by Chinese. As early as the 1920s, and into the 1950s and 1960s when the country was alienated from the West and its people were mired in poverty, some urban Chinese parents sent their daughters to ballet class after school, believing that this Western genre of art was the epitome of beauty and an educa-tional requirement for young ladies who held great expectations.
Institute of Scientific and Technical Information of China (English)
1995-01-01
HEALTH was once a matter only doctors were concerned about. But in recent years, women’s health issues have been a part of the women’s movement. A woman’s right to health and health care is now the concern of society. In the 1990s, it is becoming apparent that quality of life is of foremost importance. At the World Summit for Children held in September 1990 in New York, government leaders from over 140 countries gathered for the first time to
Directory of Open Access Journals (Sweden)
Sibel Kilinc
2011-01-01
Full Text Available Belief in a just world hypothesis is defined as the belief that the world is a just place where people generally get what they deserve. It states that individuals have a need to believe that they live in a just world; they believe in a world where people get what they deserve and where people deserve what they get. Individuals believe that who work hard or who perform good acts obtain rewards for their actions, while the sinners and the laggards receive punishments instead. Similarly, individuals want to believe that positive outcomes, whether money, success, or happiness, are obtained only by good people and, conversely, that negative outcomes only happen to bad persons. Justice beliefs have been hypothesized as adaptive for dealing with day-to-day stres. Just world beliefs protect individuals from the daily negative psychological consequences of living in what is realistically an unjust world. In addition, just world beliefs are thought to enhance feelings of security to the extent that if the individual satisfies the conditions for being "good," he or she is protected from injustice. The belief in a just world, like other positive illusions, should contribute to the maintenance of one's mental health. Belief in a just world's is discussed in two ways: personal belief in a just world's answers the question “how much justly is the world to me?”, whereas the belief in a just world's in general answers the question “how much justly is the world?”
Abdusy Syarif; Riri Fitri Sari
2011-01-01
In mobile ad hoc networks (MANETs), routing protocol plays the most important role. In the last decade, Ad hoc On-demand Distance Vector (AODV) routing protocol becomes the attention of focussed research on MANETs world wide. A lot of protocols had been proposed to improve and optimize AODV routing protocol to achieve the best in quest of reliable protocol. In this paper, we present some improvement suggestion to AODV routing protocol. Our proposed protocol, called AODV-UI, improved AODV in g...
THE BEAUTY OF THE WORLD IN PLATO’S TIMAEUS
Directory of Open Access Journals (Sweden)
O’Meara, Dominic
2014-01-01
Full Text Available In the Timaeus Plato describes the world as the ‘most beautiful’ (kallistos, 29a5 of generated things. Perhaps indeed this is the first systematic description of the beauty of the world. It is, at any rate, one of the most influential statements of the theme. The Stoics were deeply convinced by it and later, in the third century A.D., at a time when contempt and hate for the world were propagated by Gnostic movements, Plotinus, interpreting the Timaeus, would write magnificent passages on the beauty and value of the world. But what does Plato mean by the ‘beauty’ of the world? What makes the world beautiful? In this paper these questions are approached first (1 by a brief discussion of the distinction which Plato appears to make in the Timaeus between beauty and the good. In one passage (Tim. 87c ‘measure’ seems to relate to this distinction. It is suitable then (2 to look at a section of another late work of Plato, the Philebus, where the themes of beauty, goodness and measure may be compared in more detail. The theme of measure then takes us back (3 to the Timaeus, in order to examine the role played by measure, in particular mathematical measure, in constituting the beauty of the world. I discuss in detail the way in which mathematical structures make for the beauty of soul and body in the living whole that is the world.
Stemmer, Andreas; Jacobs, Heiko; Knapp, Helmut F.
1996-12-01
At the interface of micro and macro world, vision plays a fundamental role in localizing targets and positioning micro- or nanorobots relative to them. Traditionally, far- field optics are used to achieve this task. However, in most practical applications optical diffraction limits resolution to the micrometer-range although image processing may provide us relative accuracies on the order of several nanometers in a few special cases. At ambient pressure, capillary condensation of water vapor severely hampers reproducible and reversible manipulations of micrometer- sized or smaller objects since the resulting adhesive forces between tool and object easily exceed the object's weight. The size of objects also dictates the useful dimensions of sensors and actuators and generally necessitates integration of several sensing and/or actuation functions into a single device. To overcome above mentioned difficulties in accessing the micro and nano world, sensing and actuating principles derived from scanning probe microscopies such as atomic force or optical near-field provide us with the necessary extension of the capabilities offered by traditional far-field systems. A fluid environment also prevents those hard-to-control effects of capillary forces.
World Area Forecast System (WAFS)
National Oceanic and Atmospheric Administration, Department of Commerce — The World Area Forecast System (WAFS) is a worldwide system by which world area forecast centers provide aeronautical meteorological en-route forecasts in uniform...
Energy Technology Data Exchange (ETDEWEB)
Alfstad,T.
2008-10-01
This report forms part of a project entitled 'World Biofuels Study'. The objective is to study world biofuel markets and to examine the possible contribution that biofuel imports could make to help meet the Renewable Fuel Standard (RFS) of the Energy Independence and Security Act of 2007 (EISA). The study was sponsored by the Biomass Program of the Assistant Secretary for Energy Efficiency and Renewable Energy (EERE), U.S. Department of Energy. It is a collaborative effort among the Office of Policy and International Affairs (PI), Department of Energy and Oak Ridge National Laboratory (ORNL), National Renewable Energy Laboratory (NREL) and Brookhaven National Laboratory (BNL). The project consisted of three main components: (1) Assessment of the resource potential for biofuel feedstocks such as sugarcane, grains, soybean, palm oil and lignocellulosic crops and development of supply curves (ORNL). (2) Assessment of the cost and performance of biofuel production technologies (NREL). (3) Scenario-based analysis of world biofuel markets using the ETP global energy model with data developed in the first parts of the study (BNL). This report covers the modeling and analysis part of the project conducted by BNL in cooperation with PI. The Energy Technology Perspectives (ETP) energy system model was used as the analytical tool for this study. ETP is a 15 region global model designed using the MARKAL framework. MARKAL-based models are partial equilibrium models that incorporate a description of the physical energy system and provide a bottom-up approach to study the entire energy system. ETP was updated for this study with biomass resource data and biofuel production technology cost and performance data developed by ORNL and NREL under Tasks 1 and 2 of this project. Many countries around the world are embarking on ambitious biofuel policies through renewable fuel standards and economic incentives. As a result, the global biofuel demand is expected to grow very
On 1-loop diagrams in AdS space and the random disorder problem
Hung, Ling-Yan
2010-01-01
We study the complex scalar loop corrections to the boundary-boundary gauge two point function in pure AdS space in Poincare coordinates, in the presence of a boundary quadratic perturbation to the scalar. These perturbations correspond to double trace perturbations in the dual CFT and modify the boundary conditions of the bulk scalars in AdS. We find that, in addition to the usual UV divergences, the 1-loop calculation suffers from a divergence originating in the limit as the loop vertices approach the AdS horizon. We show that this type of divergence is independent of the boundary coupling, and making use of which we extract the finite relative variation of the imaginary part of the loop via Cutkosky rules as the boundary perturbation varies. Applying our methods to compute the effects of a time-dependent impurity to the conductivities using the replica trick in AdS/CFT, we find that generally an IR-relevant disorder reduces the conductivity and that in the extreme low frequency limit the correction due to ...
The Central Charge of the Warped AdS^3 Black Hole
Gupta, Kumar S; Sen, Siddhartha; Sivakumar, M
2010-01-01
The AdS/CFT conjecture offers the possibility of a quantum description for a black hole in terms of a CFT. This has ledto the study of general AdS^3 type black holes with a view to constructing an explicit toy quantum black hole model. Such a CFT description would be characterized by its central charge and the dimensions of its primary fields. Recently the expression for the central charges (C_L, C_R) of the CFT dual to the warped AdS^3 have been determined using asymptotic symmetry arguments. The central charges depend, as expected, on the warping factor. We show that topological arguments, used by Witten to constrain central charges for the BTZ black hole, can be generalized to deal with the warped AdS^3 case. Topology constrains the warped factor to be rational numbers while quasinormal modes are conjectured to give the dimensions of primary fields. We find that in the limit when warping is large or when it takes special rational values the system tends to Witten's conjectured unique CFT's with central cha...
Diving into Real World Challenges
Saldana, Matt; Rodden, Leslie
2012-01-01
In this article, the authors discuss how educators can engage students in real world learning using their academic knowledge and technical skills. They describe how school districts have discovered that the world of robotics can help students use technical skills to solve simulated problems found in the real world, while understanding the…
Institute of Scientific and Technical Information of China (English)
无
2007-01-01
New Seven Wonders of the World is a contemporary attempt to create analternative to historical lists of the Seven Wonders of the World.The result of a worldwide popularity poll was organized by the private,non-profit New Open World Corporation(NOWC).Its final list was announced on
Becoming Citizens of the World
Stewart, Vivien
2007-01-01
The globalization of economies, the digitization of work, pressing health and security issues, and changing demographics have dramatically changed our world. Unlike previous generations, U.S. high school graduates will routinely buy from the world, sell to the world, work for international companies, manage employees from other cultures and…
Evolutionary algorithms for mobile ad hoc networks
Dorronsoro, Bernabé; Danoy, Grégoire; Pigné, Yoann; Bouvry, Pascal
2014-01-01
Describes how evolutionary algorithms (EAs) can be used to identify, model, and minimize day-to-day problems that arise for researchers in optimization and mobile networking. Mobile ad hoc networks (MANETs), vehicular networks (VANETs), sensor networks (SNs), and hybrid networks—each of these require a designer’s keen sense and knowledge of evolutionary algorithms in order to help with the common issues that plague professionals involved in optimization and mobile networking. This book introduces readers to both mobile ad hoc networks and evolutionary algorithms, presenting basic concepts as well as detailed descriptions of each. It demonstrates how metaheuristics and evolutionary algorithms (EAs) can be used to help provide low-cost operations in the optimization process—allowing designers to put some “intelligence” or sophistication into the design. It also offers efficient and accurate information on dissemination algorithms topology management, and mobility models to address challenges in the ...
Chu, Chong-Sun
2016-01-01
We propose and study a holographic dual of the type IIB superstring theory of AdS_5 x S^5 in terms of the N=4 superconformal Yang-Mills theory on dS_4. We use the bulk to boundary formalism to evaluate the boundary correlation functions and verify that it agrees with the expected result in dS conformal field theory. The gauge theory is expected to be UV finite and enjoy exact SL(2,Z) strong-weak duality. As the string theory Green-Schwarz sigma model carries an infinite number of classically conserved charges, it also suggest that the superconformal Yang-Mills theory is integrable and deserves further studies.
AD/HD: POSSIBLE DIAGNOSIS AND TREATMENT
Directory of Open Access Journals (Sweden)
Karl REICHELT
2008-12-01
Full Text Available The purpose of this paper is to show that a more exact diagnosis and dietary intervention in AD/HD (Attention Deficit/Hyperactivity Disorder is possible and probable. The clinical symptom based diagnosis we suggest may be supplemented with physiological tests. A genetic and environmental inter-action is clearly involved and explainable using phenylketonuria as a model.Method: Examining peer reviewed published papers on gut to blood, blood to brain interaction and effect of interventions in AD/HD and our own studies in the field. The various treatment options are discussed.Results: It can be shown that a gut to brain activity is possible and probable, and dietary intervention is useful and probably safer than drugs. Preliminary data on a small five year follow up of dietary intervention is shown.
Constrained Delaunay Triangulation for Ad Hoc Networks
Directory of Open Access Journals (Sweden)
D. Satyanarayana
2008-01-01
Full Text Available Geometric spanners can be used for efficient routing in wireless ad hoc networks. Computation of existing spanners for ad hoc networks primarily focused on geometric properties without considering network requirements. In this paper, we propose a new spanner called constrained Delaunay triangulation (CDT which considers both geometric properties and network requirements. The CDT is formed by introducing a small set of constraint edges into local Delaunay triangulation (LDel to reduce the number of hops between nodes in the network graph. We have simulated the CDT using network simulator (ns-2.28 and compared with Gabriel graph (GG, relative neighborhood graph (RNG, local Delaunay triangulation (LDel, and planarized local Delaunay triangulation (PLDel. The simulation results show that the minimum number of hops from source to destination is less than other spanners. We also observed the decrease in delay, jitter, and improvement in throughput.
Noncommutative $q$-photon added coherent states
Dey, Sanjib
2016-01-01
We construct the photon added coherent states of a noncommutative harmonic oscillator associated to a $q$-deformed oscillator algebra. Various nonclassical properties of the corresponding system are explored, first, by studying two different types of higher order quadrature squeezing, namely the Hillery-type and the Hong--Mandel-type and, second, by testing the sub-Poissonian nature of photon statistics in higher order with the help of the correlation function and the Mandel parameter. By comparing our results with those of the usual harmonic oscillator, we notice that the quadratures and photon number distributions in noncommutative case are more squeezed for the same values of the parameters and, thus, the photon added coherent states of noncommutative harmonic oscillator may be more nonclassical in comparison to the ordinary harmonic oscillator.
Chu, Chong-Sun; Giataganas, Dimitrios
2016-11-01
We propose and study a holographic dual of the type-IIB superstring theory of AdS5×S5 in terms of the N =4 superconformal Yang-Mills theory on dS4 . We develop the bulk to boundary formalism for the computation of the correlation functions to a wide class of theories. We apply it to compute the two-point correlators in the particular duality under study and we find that they agree with the expected results in d S conformal field theory. The gauge theory is expected to be UV finite and enjoy exact S L (2 ,Z ) strong-weak duality. As the string theory Green-Schwarz sigma model carries an infinite number of classically conserved charges, it also suggests that the superconformal Yang-Mills theory is integrable and deserves further studies.
Hubeny, Veronika E.
2015-06-01
We give a brief review of the AdS/CFT correspondence, which posits the equivalence between a certain gravitational theory and a lower-dimensional non-gravitational one. This remarkable duality, formulated in 1997, has sparked a vigorous research program that has gained in breadth over the years, with applications to many aspects of theoretical (and even experimental) physics, not least to general relativity and quantum gravity. To put the AdS/CFT correspondence into historical context, we start by reviewing the relevant aspects of string theory (of which no prior knowledge is assumed). We then develop the statement of the correspondence, and explain how the two sides of the duality map into each other. Finally, we discuss the implications and applications of the correspondence, and indicate some of the current trends in this subject. The presentation attempts to convey the main concepts in a simple and self-contained manner, relegating supplementary remarks to footnotes.
Hubeny, Veronika E
2015-01-01
We give a brief review of the AdS/CFT correspondence, which posits the equivalence between a certain gravitational theory and a lower-dimensional non-gravitational one. This remarkable duality, formulated in 1997, has sparked a vigorous research program which has gained in breadth over the years, with applications to many aspects of theoretical (and even experimental) physics, not least to general relativity and quantum gravity. To put the AdS/CFT correspondence in historical context, we start by reviewing the relevant aspects of string theory (of which no prior knowledge is assumed). We then develop the statement of the correspondence, and explain how the two sides of the duality map into each other. Finally, we discuss the implications and applications of the correspondence, and indicate some of the current trends in this subject. The presentation attempts to convey the main concepts in a simple and self-contained manner, relegating supplementary remarks to footnotes.
Haas, Zygmunt; Halpern, Joseph Y.; Li, Erran L.
2002-01-01
Many ad hoc routing protocols are based on some variant of flooding. Despite various optimizations, many routing messages are propagated unnecessarily. We propose a gossiping-based approach, where each node forwards a message with some probability, to reduce the overhead of the routing protocols. Gossiping exhibits bimodal behavior in sufficiently large networks: in some executions, the gossip dies out quickly and hardly any node gets the message; in the remaining executions, a substantial fr...
Hypoglycaemia when adding sulphonylurea to metformin
DEFF Research Database (Denmark)
Andersen, Stig Ejdrup; Christensen, Mikkel
2016-01-01
of hypoglycaemia was lowest with gliclazide compared to glipizide (OR 0.22, CrI: 0.05 to 0.96), glimepiride (OR 0.40, CrI: 0.13 to 1.27), and glibenclamide (OR 0.21, CrI: 0.03 to 1.48). A major limitation is varying definitions of hypoglycaemia across studies. CONCLUSIONS: When added to metformin, gliclazide...
Merged Sounding Value-Added Product
Energy Technology Data Exchange (ETDEWEB)
Troyan, D
2010-03-03
The Merged Sounding value-added product (VAP) uses a combination of observations from radiosonde soundings, the microwave radiometer (MWR), surface meteorological instruments, and European Centre for Medium-Range Weather Forecasts (ECMWF) model output with a sophisticated scaling/interpolation/smoothing scheme in order to define profiles of the atmospheric thermodynamic state at one-minute temporal intervals and a total of 266 altitude levels.
DAWN: Dynamic Ad-hoc Wireless Network
2016-06-19
Wireless Networks, , ( ): . doi: Ning Li, Jennifer C. Hou. Localized Topology Control Algorithms for Heterogeneous Wireless Networks, IEEE ...Multi-User Diversity in Single-Radio OFDMA AdHoc Networks Based on Gibbs Sampling, IEEE Milcom . 03-NOV-10, . : , TOTAL: 1 Number of Peer-Reviewed...Networks, ( ) Hui Xu, , Xianren Wu, , Hamid R. Sadjadpour, , J.J. Garcia-Luna-Aceves, . A Unified Analysis of Routing Protocols inMANETs, IEEE
Geodesic Motions in AdS Soliton Background Space-time
Shi, Han-qing
2016-01-01
We study both massive and massless particle's geodesic motion in the background of general dimensional AdS-Sol space-time. We find that the massive particles oscillate along the radial direction, while massless particles experience one-time bouncing as they approach the "horizon" line of the soliton. Our results provide a direct way to understand the negative energy/masses leading to the AdS-Sol geometry. As a potential application, we extend the point particle to a 3-brane and fix the background as a 5+1 dimension AdS-Sol, thus obtain a very natural bouncing/cyclic cosmological model.
Covariant anomalies and Hawking radiation from Kaluza–Klein AdS black holes
Indian Academy of Sciences (India)
Chuan-Yi Bai
2013-02-01
In this paper, Hawking radiation is studied from four-dimensional (4D) Kaluza–Klein (KK) AdS black holes via the method of anomaly cancellation. The {|bf KK-AdS} black hole considered is a non-extremal charged rotating solution in the theory of 4D gauged supergravity. Its Hawking fluxes of electric charge, angular momentum and energy momentum tensor are derived here. Our results support the common view that Hawking radiation is the quantum effect arising at the event horizon.
On periodically driven AdS/CFT
Auzzi, Roberto; Gudnason, Sven Bjarke; Rabinovici, Eliezer
2013-01-01
We use the AdS/CFT correspondence to study a thermally isolated conformal field theory in four dimensions which undergoes a repeated deformation by an external periodic time-dependent source coupled to an operator of dimension Delta. The initial state of the theory is taken to be at a finite temperature. We compute the energy dissipated in the system as a function of the frequency and of the dimension Delta of the perturbing operator. This is done in the linear response regime. In order to study the details of thermalization in the dual field theory, the leading-order backreaction on the AdS black brane metric is computed. The evolution of the event and the apparent horizons is monitored; the increase of area in each cycle coincides with the increase in the equilibrium entropy corresponding to the amount of energy dissipated. The time evolution of the entanglement entropy of a spherical region and that of the two-points function of a probe operator with a large dimension are also inspected; we find a delay in...
Ad Serving Using a Compact Allocation Plan
Chen, Peiji; Mandalapu, Srinath; Nagarajan, Chandrashekhar; Shanmugasundaram, Jayavel; Vassilvitskii, Sergei; Vee, Erik; Yu, Manfai; Zien, Jason
2012-01-01
A large fraction of online display advertising is sold via guaranteed contracts: a publisher guarantees to the advertiser a certain number of user visits satisfying the targeting predicates of the contract. The publisher is then tasked with solving the ad serving problem - given a user visit, which of the thousands of matching contracts should be displayed, so that by the expiration time every contract has obtained the requisite number of user visits. The challenges of the problem come from (1) the sheer size of the problem being solved, with tens of thousands of contracts and billions of user visits, (2) the unpredictability of user behavior, since these contracts are sold months ahead of time, when only a forecast of user visits is available and (3) the minute amount of resources available online, as an ad server must respond with a matching contract in a fraction of a second. We present a solution to the guaranteed delivery ad serving problem using {\\em compact allocation plans}. These plans, computed offl...
Data Confidentiality in Mobile Ad hoc Networks
Directory of Open Access Journals (Sweden)
Hamza Aldabbas
2012-03-01
Full Text Available Mobile ad hoc networks (MANETs are self-configuring infrastructure-less networks comprised of mobile nodes that communicate over wireless links without any central control on a peer-to-peer basis.These individual nodes act as routers to forward both their own data and also their neighbours’ data by sending and receiving packets to and from other nodes in the network. The relatively easy configuration and the quick deployment make ad hoc networks suitable the emergency situations (such as human or natural disasters and for military units in enemy territory. Securing data dissemination between these nodes in such networks, however, is a very challenging task. Exposing such information to anyone else other than the intended nodes could cause a privacy and confidentiality breach, particularly in military scenarios. In this paper we present a novel framework to enhance the privacy and data confidentiality in mobile ad hoc networks by attaching the originator policies to the messages as they are sent between nodes. We evaluate our framework using the Network Simulator (NS-2 to check whether the privacy and confidentiality of the originator are met. For this we implemented the Policy Enforcement Points (PEPs, as NS-2 agents that manage and enforce the policies attached to packets at every node in the MANET.
Drag cancellation by added-mass pumping
Giorgio-Serchi, F
2016-01-01
A submerged body subject to a sudden shape-change experiences large forces due to the variation of added-mass energy. While this phenomenon has been studied for single actuation events, application to sustained propulsion requires studying \\textit{periodic} shape-change. We do so in this work by investigating a spring-mass oscillator submerged in quiescent fluid subject to periodic changes in its volume. We develop an analytical model to investigate the relationship between added-mass variation and viscous damping and demonstrate its range of application with fully coupled fluid-solid Navier-Stokes simulations at large Stokes number. Our results demonstrate that the recovery of added-mass kinetic energy can be used to completely cancel the viscous damping of the fluid, driving the onset of sustained oscillations with amplitudes as large as four times the average body radius $r_0$. A quasi-linear relationship is found to link the terminal amplitude of the oscillations $X$, to the extent of size change $a$, wit...
ADS: The Next Generation Search Platform
Accomazzi, Alberto; Henneken, Edwin A; Chyla, Roman; Luker, James; Grant, Carolyn S; Thompson, Donna M; Holachek, Alexandra; Dave, Rahul; Murray, Stephen S
2015-01-01
Four years after the last LISA meeting, the NASA Astrophysics Data System (ADS) finds itself in the middle of major changes to the infrastructure and contents of its database. In this paper we highlight a number of features of great importance to librarians and discuss the additional functionality that we are currently developing. Starting in 2011, the ADS started to systematically collect, parse and index full-text documents for all the major publications in Physics and Astronomy as well as many smaller Astronomy journals and arXiv e-prints, for a total of over 3.5 million papers. Our citation coverage has doubled since 2010 and now consists of over 70 million citations. We are normalizing the affiliation information in our records and, in collaboration with the CfA library and NASA, we have started collecting and linking funding sources with papers in our system. At the same time, we are undergoing major technology changes in the ADS platform which affect all aspects of the system and its operations. We hav...
International Energy Agency. Paris
2014-01-01
The global energy landscape is evolving at a rapid pace, reshaping long-held expectations for our energy future. The 2014 edition of the World Energy Outlook (WEO) will incorporate all the latest data and developments to produce a comprehensive and authoritative analysis of medium- and longer-term energy trends. It will complement a full set of energy projections – which extend from today through, for the first time, the year 2040 – with strategic insights into their meaning for energy security, the economy and the environment. Oil, natural gas, coal, renewables and energy efficiency will be covered, along with updates on trends in energy-related CO2 emissions, fossil-fuel and renewable energy subsidies, and universal access to modern energy services.
Institute of Scientific and Technical Information of China (English)
无
2007-01-01
@@ Knowledge of the stress field in the Earth's crust is a key issue for the understanding of geodynamic processes,seismic hazard assessment, and stability of underground openings such as waste disposals, tunnels, mines or wells, and reservoir management. The World Stress Map project is a collaborative project of academia,industry and governmental organizations that aims to understand the states and sources of tectonic stresses in the Earth's crust. We present the Worm Stress Map at 1:46,000,000 scale as a result of more than two decades of international collaboration. The map reveals that the first-order pattern of stress is of plate-wide scale, indicating that plate boundary forces are the major control of the stress orientations and the tectonic regime.
Nikodem, Jan; Innovative Technologies in Management and Science
2015-01-01
This carefully edited book presents recent research in Innovative Technologies in Management and Science, representing a widely spread interdisciplinary research area with many applications in various disciplines including engineering, medicine, technology, or environment, among others. It consists of eleven invited and scholarly edited chapters written by respectable researchers and experts in the fields that integrate ideas and novel concepts in Intelligent Systems and Informatics. Most of the chapters were selected from the initial contributions to the World of Innovation Conference held on April 3, 2012 in Wroclaw, Poland. The contributions are focusing on research and development of the latest IT technologies, in the field of Cloud Computing, IT modeling, as well as optimization problems. The chapters presented can be grouped into three categories: Innovation supported by Clouds Technology, Innovation proposals in management area, and Theoretical refinement for innovative solutions.
Energy Technology Data Exchange (ETDEWEB)
NONE
1995-09-29
As part of the EIA program to provide energy information, this analysis report presents the current status and projections through 2015 of nuclear capacity, generation, and fuel cycle requirements for all countries in the world using nuclear power to generate electricity for commercial use. It also contains information and forecasts of developments in the uranium market. Long-term projections of US nuclear capacity, generation, and spent fuel discharges for two different scenarios through 2040 are developed for the Department of Energy`s Office of Civilian Radioactive Waste Management (OCRWM). In turn, the OCRWM provides partial funding for preparation of this report. The projections of uranium requirements are provided to the Organization for Economic Cooperation and Development (OECD) for preparation of the Nuclear Energy Agency/OECD report, Summary of Nuclear Power and Fuel Cycle Data in OECD Member Countries.
Sornette, Didier
2014-01-01
Using the mechanics of creep in material sciences as a metaphor, we present a general framework to understand the evolution of financial, economic and social systems and to construct scenarios for the future. In a nutshell, highly non-linear out-of-equilibrium systems subjected to exogenous perturbations tend to exhibit a long phase of slow apparent stable evolution, which are nothing but slow maturations towards instabilities, failures and changes of regimes. With examples from history where a small event had a cataclysmic consequence, we propose a novel view of the current state of the world via the logical scenarios that derive, avoiding the traps of an illusionary stability and simple linear extrapolation. The endogenous scenarios are "muddling along", "managing through" and "blood red abyss". The exogenous scenarios are "painful adjustment" and "golden east".
Pappalardo, R. T.
2004-01-01
When the twin Voyager spacecraft cruised past Jupiter in 1979, they did more than rewrite the textbooks on the giant planet. Their cameras also unveiled the astounding diversity of the four planet-size moons of ice and stone known as the Galilean satellites. The Voyagers revealed the cratered countenance of Callisto, the valleys and ridges of Ganymede, the cracked face of Europa, and the spewing volcanoes of Io. But it would take a spacecraft named for Italian scientist Galileo, who discovered the moons in 1610, to reveal the true complexity of these worlds and to begin to divulge their interior secrets. Incredibly, the Galileo data strongly suggest that Jupiter's three large icy moons (all but rocky Io) hide interior oceans.
Energy Technology Data Exchange (ETDEWEB)
NONE
1994-12-01
As part of the EIA program to provide energy information, this analysis report presents the current status and projections through 2010 of nuclear capacity, generation, and fuel cycle requirements for all countries in the world using nuclear power to generate electricity for commercial use. It also contains information and forecasts of developments in the uranium market. Long-term projections of US nuclear capacity, generation, and spent fuel discharges for three different scenarios through 2040 are developed for the Department of Energy`s Office of Civilian Radioactive Waste Management (OCRWM). In turn, the OCRWM provides partial funding for preparation of this report. The projections of uranium requirements are provided to the Organization for Economic Cooperation and Development (OECD) for preparation of the Nuclear Energy Agency/OECD report, Summary of Nuclear Power and Fuel Cycle Data in OECD Member Countries.
Energy Technology Data Exchange (ETDEWEB)
NONE
2010-11-09
The world appears to be emerging from the worst economic crisis in decades. Many countries have made pledges under the Copenhagen Accord to reduce greenhouse-gas emissions. Commitments have also been made by the G-20 and APEC to phase out inefficient fossil-fuel subsidies. Are we, at last, on the path to a secure, reliable and environmentally sustainable energy system? Updated projections of energy demand, production, trade and investment, fuel by fuel and region by region to 2035 are provided in the 2010 edition of the World Energy Outlook (WEO). It includes, for the first time, a new scenario that anticipates future actions by governments to meet the commitments they have made to tackle climate change and growing energy insecurity. WEO-2010 shows: what more must be done and spent to achieve the goal of the Copenhagen Accord to limit the global temperature increase to 2 deg. C and how these actions would impact on oil markets; how emerging economies -- led by China and India -- will increasingly shape the global energy landscape; what role renewables can play in a clean and secure energy future; what removing fossil-fuel subsidies would mean for energy markets, climate change and state budgets; the trends in Caspian energy markets and the implications for global energy supply; the prospects for unconventional oil; and how to give the entire global population access to modern energy services. With extensive data, projections and analysis, this publication provides invaluable insights into how the energy system could evolve over the next quarter of a century. The book is essential reading for anyone with a stake in the energy sector.
Lunine, Jonathan I.
2017-02-01
Ocean worlds is the label given to objects in the solar system that host stable, globe-girdling bodies of liquid water-"oceans". Of these, the Earth is the only one to support its oceans on the surface, making it a model for habitable planets around other stars but not for habitable worlds elsewhere in the solar system. Elsewhere in the solar system, three objects-Jupiter's moon Europa, and Saturn's moons Enceladus and Titan-have subsurface oceans whose existence has been detected or inferred by two independent spacecraft techniques. A host of other bodies in the outer solar system are inferred by a single type of observation or by theoretical modeling to have subsurface oceans. This paper focusses on the three best-documented water oceans beyond Earth: those within Europa, Titan and Enceladus. Of these, Europa's is closest to the surface (less than 10 km and possibly less than 1 km in places), and hence potentially best suited for eventual direct exploration. Enceladus' ocean is deeper-5-40 km below its surface-but fractures beneath the south pole of this moon allow ice and gas from the ocean to escape to space where it has been sampled by mass spectrometers aboard the Cassini Saturn Orbiter. Titan's ocean is the deepest-perhaps 50-100 km-and no evidence for plumes or ice volcanism exist on the surface. In terms of the search for evidence of life within these oceans, the plume of ice and gas emanating from Enceladus makes this the moon of choice for a fast-track program to search for life. If plumes exist on Europa-yet to be confirmed-or places can be located where ocean water is extruded onto the surface, then the search for life on this lunar-sized body can also be accomplished quickly by the standards of outer solar system exploration.
Reciprocity, World Prices and Welfare
DEFF Research Database (Denmark)
Raimondos-Møller, Pascalis; Woodland, Alan D.
We examine in detail the circumstances under which reciprocity, as defined in Bagwell and Staiger (1999), leads to fixed world prices. We show that a change of tariffs satisfying reciprocity does not necessarily imply constant world prices in a world of many goods and countries. While...... it is possible to find tariff reforms that are consistent with both reciprocity and constant world prices, these reforms do not follow from the reciprocity condition, but rather from the requirement of unchanged world prices. We propose an alternative reciprocity rule that is guaranteed to raise the welfare...
A reference accelerator scheme for ADS applications
Energy Technology Data Exchange (ETDEWEB)
Biarrotte, Jean-Luc [CNRS/IN2P3, Institut de Physique Nucleaire, 91406 Orsay (France)]. E-mail: biarrott@ipno.in2p3.fr; Bousson, Sebastien [CNRS/IN2P3, Institut de Physique Nucleaire, 91406 Orsay (France); Junquera, Tomas [CNRS/IN2P3, Institut de Physique Nucleaire, 91406 Orsay (France); Mueller, Alex C. [CNRS/IN2P3, Institut de Physique Nucleaire, 91406 Orsay (France); Olivier, Aurelia [CNRS/IN2P3, Institut de Physique Nucleaire, 91406 Orsay (France)
2006-06-23
Accelerator Driven Systems (ADS) for transmutation of nuclear waste typically require 350MeV-1GeV accelerators delivering proton fluxes of 5-10mA for demonstrators, and 20-50mA for large industrial systems. Thus, such machines belong to the category of the so-called HPPA (High-Power Proton Accelerators), with multi-megawatt beam power. HPPA are presently developed and constructed at great pace for their broad utility in fundamental or applied science. Compared to other HPPA, many features and requirements are similar for the ADS driver. However, there is a need for exceptional reliability: because of the induced thermal stress to the sub-critical core, the number of unwanted 'beam-trips' should not exceed a few per year, a requirement that is several orders of magnitude above usual performance. Consecutive to the work of the European Technical Working Group (ETWG) on ADS, the Preliminary Design Study of an Experimental ADS (PDS-XADS) was launched in 2001 as a 5th Framework Program EC project. A special Working Package (WP3) was dedicated to the accelerator design, taking especially into account that the issue of 'beam-trips' could be a potential 'show-stopper' for ADS technology in general. A reference solution, based on a linear superconducting accelerator with its associated doubly achromatic beam line, has been worked out to some detail. For high reliability, the proposed design is intrinsically fault tolerant, relying on highly modular 'de-rated' components associated to a fast digital feedback system. The proposed solution also appears to be robust concerning operational aspects like maintenance and radioprotection. A roadmap for construction as well as the required consolidated budget was elaborated. A program for the remaining R and D, focused on experimental reliability demonstration of prototypical components has been elaborated. This R and D will be performed in the 6th Framework Program EC project EUROTRANS, which
G\\"odel, warped AdS$_3$ and flows from $\\mathcal{N} = (0,2)$ SCFTs
Colgáin, Eoin Ó
2015-01-01
We present all timelike supersymmetric solutions to 3D U(1)$^3$ gauged supergravity, a known consistent truncation of string theory. We uncover a rich vacuum structure, including an infinite class of new timelike (G\\"odel) and spacelike warped AdS$_3$ critical points. We outline the construction of holographic flows interpolating between AdS$_3$ and warped AdS$_3$ critical points.
Renormalization, averaging, conservation laws and AdS (in)stability
Energy Technology Data Exchange (ETDEWEB)
Craps, Ben [Theoretische Natuurkunde, Vrije Universiteit Brussel and The International Solvay Institutes,Pleinlaan 2, B-1050 Brussels (Belgium); Evnin, Oleg [Department of Physics, Faculty of Science, Chulalongkorn University,Thanon Phayathai, Pathumwan, Bangkok 10330 (Thailand); Theoretische Natuurkunde, Vrije Universiteit Brussel and The International Solvay Institutes,Pleinlaan 2, B-1050 Brussels (Belgium); Vanhoof, Joris [Theoretische Natuurkunde, Vrije Universiteit Brussel and The International Solvay Institutes,Pleinlaan 2, B-1050 Brussels (Belgium)
2015-01-21
We continue our analytic investigations of non-linear spherically symmetric perturbations around the anti-de Sitter background in gravity-scalar field systems, and focus on conservation laws restricting the (perturbatively) slow drift of energy between the different normal modes due to non-linearities. We discover two conservation laws in addition to the energy conservation previously discussed in relation to AdS instability. A similar set of three conservation laws was previously noted for a self-interacting scalar field in a non-dynamical AdS background, and we highlight the similarities of this system to the fully dynamical case of gravitational instability. The nature of these conservation laws is best understood through an appeal to averaging methods which allow one to derive an effective Lagrangian or Hamiltonian description of the slow energy transfer between the normal modes. The conservation laws in question then follow from explicit symmetries of this averaged effective theory.
Finite action principle for Chern-Simons AdS gravity
Mora, P; Troncoso, R; Zanelli, J
2004-01-01
A finite action action principle for Chern-Simons AdS gravity is presented. The construction is carried out in detail first in five dimensions, where the bulk action is given by a particular combination of the Einstein-Hilbert action with negative cosmological constant and a Gauss-Bonnet term; and is then generalized for arbitrary odd dimensions. The boundary term needed to render the action finite is singled out demanding the action to attain an extremum for an appropriate set of boundary conditions. The boundary term is a local function of the fields at the boundary and is sufficient to render the action finite for asymptotically AdS solutions, without requiring background fields. It is shown that the Euclidean continuation of the action correctly describes the black hole thermodynamics in the canonical ensemble. Additionally, background independent conserved charges associated with the asymptotic symmetries can be written as surface integrals by direct application of Noether's theorem.
Stability of warped AdS3 black holes in Topologically Massive Gravity under scalar perturbations
Ferreira, Hugo R C
2013-01-01
We demonstrate that the warped AdS3 black hole solutions of Topologically Massive Gravity are classically stable against massive scalar field perturbations by analysing the quasinormal and bound state modes of the scalar field. In particular, it is found that although classical superradiance is present it does not give rise to superradiant instabilities. The stability is shown to persist even when the black hole is enclosed by a stationary mirror with Dirichlet boundary conditions. This is a surprising result in view of the similarity between the causal structure of the warped AdS3 black hole and the Kerr spacetime in 3+1 dimensions. This work provides the foundations for the study of quantum field theory in this spacetime.
Tachyon inflation in an AdS braneworld with back-reaction
Bilic, Neven; Djordjevic, Goran; Milosevic, Milan
2016-01-01
We analyze the inflationary scenario based on the tachyon field coupled with the radion of the second Randall-Sundrum model (RSII). The tachyon Lagrangian is derived from the dynamics of a 3-brane moving in the five dimensional bulk. The AdS$_5$ geometry of the bulk is extended to include the radion. Using the Hamiltonian formalism we find four nonlinear field equations supplemented by the modified Friedmann equations of the RSII braneworld cosmology. After a suitable rescaling we reduce the parameters of our model to only one free parameter related to the brane tension and the AdS$_5$ curvature. We solve the equations numerically assuming a reasonably wide range of initial conditions determined by physical considerations. Varying the free parameter and initial conditions we confront our results with the Planck 2015 data.
AdS$_5$ vacua from type IIB supergravity on $T^{1,1}$
Louis, Jan
2016-01-01
We study maximally supersymmetric Anti-de Sitter backgrounds in consistent N=2 truncations of type IIB supergravity compactified on the Sasaki-Einstein manifold $T^{1,1}$. In particular, we focus on truncations that contain fields coming from the nontrivial second and third cohomology forms on $T^{1,1}$. These give rise to N=2 supergravity coupled to two vector- and two hypermultiplets (Betti-vector truncation) or one vector- and three hypermultiplets (Betti-hyper truncation), respectively. We find that both truncations admit AdS$_5$ backgrounds with the gauge group always being broken but containing at least an $U(1)_R$ factor. Moreover, in both cases we show that the moduli space of AdS vacua is nontrivial and of maximal dimension. Finally, we explicitly compute the metrics on these moduli spaces.