New phase transitions in Chern-Simons matter theory

Applying the machinery of random matrix theory and Toeplitz determinants we study the level k, U(N) Chem-Simons theory coupled with fundamental matter on S-2 x S-1 at finite temperature T. This theory admits a discrete matrix integral representation, i.e. a unitary discrete matrix model of two-dimensional Yang Mills theory. In this study, the effective partition function and phase structure of the Chem-Simons matter theory, in a special case with an effective potential namely the Gross-Witten-Wadia potential, are investigated. We obtain an exact expression for the partition function of the Chem-Simons matter theory as a function of k, N, T, for finite values and in the asymptotic regime. In the Gross-Witten-Wadia case, we show that ratio of the Chem-Simons matter partition function and the continuous two-dimensional Yang Mills partition function, in the asymptotic regime, is the Tracy-Widom distribution. Consequently, using the explicit results for free energy of the theory, new second-order and third-order phase transitions are observed. Depending on the phase, in the asymptotic regime, Chem-Simons matter theory is represented either by a continuous or discrete two-dimensional Yang-Mills theory, separated by a third-order domain wall. (C) 2015 The Author. Published by Elsevier B.V.Peer reviewe

The Effect Of Task Complexity And Task Condition On Iranian Efl Learners' Accuracy, Complexity And Fluency Of Written Task Performance

Kajian ini bertujuan mengkaji bagaimana peningkatan tahap kekompleksan tugasan (tugasan Here-and-Now vs. There-and-Then) mempengaruhi prestasi tugasan penulisan pelajar EFL Iran, semasa melaksanakan tugasan open vs. closed yang diutarakan dalam hipotesis Robinson's Cognition (2001). Seramai 64 orang pelajar tahun satu ijazah pertama yang belajar di Universiti Azad, Gorgan, Iran terlibat sama dalam kajian ini. Mereka dipilih secara rawak dan dibahagikan ke dalam dua kumpulan yang sama: satu kumpulan didedahkan dengan tugasan Here-and-Now dan satu kumpulan lagi didedahkan dengan tugasan Thereand- Then . Setiap kumpulan diminta untuk menceritakan dua jenis cerita yang berbeza pada dua keadaan yang juga berbeza, iaitu open vs. closed. Dalam empat kumpulan eksperimen, peserta menonton cerita kartun, yang merupakan cerita bergambar 9-rangka. Kemudiannya, prestasi penulisan mereka dinilai atau diukur bagi kekompleksan, ketepatan, dan kelancaran (complexity, accuracy, and fluency, CAP). Bagi menguji cara dua variabel bebas daripada tugasan Here-and-Now dan There-and-Then memberi kesan terhadap variabel bersandar, maka skor kasar peserta dimasukkan dalam perisian komputer SPSS (version 20). The purpose of this study is to investigate how increasing the level of task complexity (Here-and-Now vs. There-and-Then tasks) influences the written task performance of Iranian EFL Learners while performing open vs. closed tasks led by Robinson's Cognition Hypothesis (2001). Sixty four first year undergraduate students studying at Islamic Azad University of Gorgan, Iran served as the participants of this study. They were randomly selected and divided into two equal groups of those with Here-and-Now tasks and those with There-and-Then tasks. Each group was asked to narrate two different types of stories under the two different conditions, open vs. closed. In the four experimental groups, the participants were presented with the cartoon picture which was a nine-frame picture story. Then, their writing performance was measured for complexity, accuracy, and fluency (CAF). To test the way the two independent variables of Here-and-Now task and There-and-Then task affect the dependent variables, the raw scores of the participants were fed into the computer software SPSS (version 20)

Shear viscosity of a highly excited string and the black hole membrane paradigm

Black hole membrane paradigm states that a certain viscous membrane seems to be sitting on a stretched horizon of a black hole from the viewpoint of a distant observer. We show that the shear viscosity of the fictitious membrane can be reproduced by a highly excited string covering the stretched horizon except for a numerical coefficient.Comment: 22 pages, no figure, minor correction

Mahler Measuring the Genetic Code of Amoebae

Amoebae from tropical geometry and the Mahler measure from number theory play important roles in quiver gauge theories and dimer models. Their dependencies on the coefficients of the Newton polynomial closely resemble each other, and they are connected via the Ronkin function. Genetic symbolic regression methods are employed to extract the numerical relationships between the 2d and 3d amoebae components and the Mahler measure. We find that the volume of the bounded complement of a d-dimensional amoeba is related to the gas phase contribution to the Mahler measure by a degree-d polynomial, with d = 2 and 3. These methods are then further extended to numerical analyses of the non-reflexive Mahler measure. Furthermore, machine learning methods are used to directly learn the topology of 3d amoebae, with strong performance. Additionally, analytic expressions for boundaries of certain amoebae are given.Comment: 45 pages; 33 Figure

On Finite Noncommutativity in Quantum Field Theory

We consider various modifications of the Weyl-Moyal star-product, in order to obtain a finite range of nonlocality. The basic requirements are to preserve the commutation relations of the coordinates as well as the associativity of the new product. We show that a modification of the differential representation of the Weyl-Moyal star-product by an exponential function of derivatives will not lead to a finite range of nonlocality. We also modify the integral kernel of the star-product introducing a Gaussian damping, but find a nonassociative product which remains infinitely nonlocal. We are therefore led to propose that the Weyl-Moyal product should be modified by a cutoff like function, in order to remove the infinite nonlocality of the product. We provide such a product, but it appears that one has to abandon the possibility of analytic calculation with the new product.Comment: 13 pages, reference adde

Early age measurement of the coefficient of thermal expansion of concrete: a new test setup based on internal heating/cooling

Um dos fatoresque influencia a durabilidade das estruturas de betão armado é o aparecimento de fendas nas primeiras idades devido às tensões internas que se geram por restrição de deformações térmicas durante a cura. A sensibilidade da deformação térmica do betão, representada pelo coeficiente de dilatação térmica (CDT), é uma propriedade que se altera durante as primeiras idades,devidoàs modificações micro-estruturais que ocorrem durante a hidratação do cimento. O conhecimento da evolução do CDTnas primeiras idades é fundamental para uma correta previsão das extensões e tensões internas que se geram logo após a presa do betão. Neste trabalho é apresentado um método integrado para determinar a evolução do CDT de provetes de betão desdeidades anteriores à finalizaçãoda presa, ultrapassando deste modo as principais limitações dos métodos atualmente utilizados para determinação deste coeficienteem materiais cimentícios. O método proposto consiste na exposição de um provete de betão a ciclos de variações térmicas de ±2.5°C,tendo-se desenvolvido um molde de ensaio que permite a leitura da resposta do provete durante as primeiras idades. Asvariações térmicassão impostasatravés da imersão do molde de ensaio em água, a temperatura controlada, e impondo a circulação dessa água no interior do provete através de um tubo em espiral embutido, permitindo desta forma reduzir o gradiente de temperatura entre a superfície e o núcleo e, consequentemente, o tempo de duração dos ciclos térmicos.No presente trabalho são testadas diferentes composições de betão para verificar a aplicabilidade do método proposto para determinação do CDT do betão nas primeiras idades, tendo-se obtido resultados que estão em acordo com o atual estado da arteOne of thefactors influencing the durability of reinforced concrete structures is the occurrence of cracking during the early ages, caused by the internal stresses generated by restrained thermal deformations during cement hydration. Thermal deformation sensitivity, represented by its coefficient of thermal expansion (CTE), is a property that changes during early ages due to, essentially, micro-structural changes that occur during cement hydration.Knowing the evolution of the CTE sinceearly ages is essential for a correct prediction of the internal stresses that occur right after setting of the concrete. In this work, an integrated methodfor determination of concreteCTE evolution duringthe early ages is proposed, in which the main limitationsof the current methods are circumvented. The proposed method consists in exposing a concrete specimen to thermalvariations of ±2.5°C,and a test rig that enables measuringthe specimen’sresponse to those thermal variations since early ages. The thermal variationis imposed by immersing the concrete specimen in a water bath, with controlled temperature, and imposing water circulation inside the specimen through an embedded spiral tube. This allows reducingthe difference between the surface and the core temperatures,andso minimizingthe duration of thermal cycles. In the present work several concrete compositions are tested in order to verify the applicability of the proposed method for determination of concrete CTE in early ages,beingobserved that the results are in accordance with the current state of the artPOCI-01-0145-FEDER-007457 (CONSTRUCT -Institute of R&D in Structures and Construction) e POCI-01-0145-FEDER-007633 (ISISE), financiados por fundos FEDER através do COMPETE2020 -Programa Operacional Competitividade e Internacionalização (POCI), e por fundos nacionais através da FCT –Fundação para a Ciência e Tecnologia. Agradece-se ainda à FCT e FEDER (COMPETE2020) o financiamento do projeto IntegraCrete PTDC/ECM-EST/1056/2014 (POCI-01-0145-FEDER-016841

Mapping local patterns of childhood overweight and wasting in low- and middle-income countries between 2000 and 2017

A double burden of malnutrition occurs when individuals, household members or communities experience both undernutrition and overweight. Here, we show geospatial estimates of overweight and wasting prevalence among children under 5 years of age in 105 low- and middle-income countries (LMICs) from 2000 to 2017 and aggregate these to policy-relevant administrative units. Wasting decreased overall across LMICs between 2000 and 2017, from 8.4% (62.3 (55.1–70.8) million) to 6.4% (58.3 (47.6–70.7) million), but is predicted to remain above the World Health Organization’s Global Nutrition Target of <5% in over half of LMICs by 2025. Prevalence of overweight increased from 5.2% (30 (22.8–38.5) million) in 2000 to 6.0% (55.5 (44.8–67.9) million) children aged under 5 years in 2017. Areas most affected by double burden of malnutrition were located in Indonesia, Thailand, southeastern China, Botswana, Cameroon and central Nigeria. Our estimates provide a new perspective to researchers, policy makers and public health agencies in their efforts to address this global childhood syndemic