Matrix Inflation and the Landscape of its Potential

Recently we introduced an inflationary setup in which the inflaton fields are matrix valued scalar fields with a generic quartic potential, M-flation. In this work we study the landscape of various inflationary models arising from M-flation. The landscape of the inflationary potential arises from the dynamics of concentric multiple branes in appropriate flux compactifications of string theory. After discussing the classical landscape of the theory we study the possibility of transition among various inflationary models appearing at different points on the landscape, mapping the quantum landscape of M-flation. As specific examples, we study some two-field inflationary models arising from this theory in the landscape.Comment: v1: 34 pages, 5 figures; v2: To be published in JCAP; v3: JCAP versio

Thomas Hobbes’ views on Philosophy, State of Nature and International Relations

The state of nature of Hobbes is like a reflection of the depression of 1640s that prevailed in the United Kingdom. The basic concept that determines the state of nature is individuality. This phenomenon is the expression of individuality, the beginning of Renaissance but not of full competence, of expressing individuality, liberating oneself from doctrinal teachings and medieval conceptions. According to Hobbes, human beings are individuals who have the desire and choice to choose. The person's ability to use his will and preference determines his happiness or unhappiness. The emotions of feeling, fear, desire etc. which are the basic characteristics of human life, are not merely physical and factual phenomenon, but a moral phenomenon that becomes evident by loving, enjoying or disliking, desiring or avoiding oneself. For Hobbes, human life is competition and struggle. As a creature that thinks of the future, human beings are constantly struggling to secure their future ambitions. It is the basic survival condition of a person that wants to be sovereign. It is inevitable that people who are equal in terms of physical and mental force will fight everyone in natural condition. This paper tries to elucidate Thomas Hobbes’ understandings of the concepts of philosophy, state and state of nature. This article will further try to shed light on the Thomas Hobbes’s views on International Relations

Wave Propagation in Viscoelastic Dielectric Elastomer Media

Dielectric elastomers (DEs) are capable of producing large deformation under electric stimuli, which makes them desirable materials for a variety of applications including biomimetics, dynamics, robotics, energy harvesting, and waveguide devices. In general, DEs possess intrinsic hyperelasticity and viscosity. Such material properties may significantly affect the dynamic performance of DE-based devices. The delicate interplay among electromechanical coupling, large deformation, material viscosity and dynamics makes modeling of the performance of DE-based devices more challenging. Therefore, in order to provide guidelines for the optimal design of DE waveguide devices, it is essential to develop appropriate and reliable models, and efficient numerical methods to examine their performance first. In this thesis, by integrating the state-of-art finite-deformation viscoelasticity theory into the framework of small-amplitude wave propagation superposed on a finitely deformed medium, the Rayleigh-Lamb wave propagation in a viscoelastic DE medium is investigated. Simulation results have demonstrated the effects of material viscosity, status of relaxation, external electric load, and mechanical pre-stretch on the dispersion behavior of the wave. For both pure elastic and viscoelastic DE media, waves with certain frequencies could be filtered by actively tuning electric loads. Moreover, some interesting findings conclude that the material viscoelasticity may cause some significant changes in the wave dispersion behavior. Therefore, incorporating the material viscosity in modeling DE waveguide is expected to provide more accurate prediction on their performance. This thesis will help to better understand the fundamentals of wave propagation in DE media and trigger more innovative and optimal design for DE waveguide applications

Bowel Obstruction due to Migration of an Intragastric Balloon Necessitating Surgical Removal before Completion of the Recommended 6 Months

We report a 25-year-old man with small bowel obstruction due to migration of a saline-filled intragastric balloon before the completion of the recommended 6 months of treatment who presented to the emergency department with abdominal pain. The patient had received a gastric balloon insertion 5 months prior. Within 24 hours of the original procedure, he noticed urine staining. The results of an endoscopy conducted the next day were normal. After ruling out other possible complications using endoscopy and confirming the diagnosis by computed tomography (CT) scan and conservative treatment for 48 hours the patient underwent surgery and the balloon was extracted. Due to the growing prevalence of obesity and the modalities used for treating it, physicians should be familiar with the side effects of each option and their presenting symptoms as well as the differential diagnosis they should not miss. Physicians must also improve their knowledge of how to approach these patients to avoid life-threatening complications caused by these modalities

Extensions of AdS_5 x S^5 and the Plane-wave Superalgebras and Their Realization in the Tiny Graviton Matrix Theory

In this paper we consider all consistent extensions of the AdS_5 x S^5 superalgebra, psu(2,2|4), to incorporate brane charges by introducing both bosonic and fermionic (non)central extensions. We study the Inonu-Wigner contraction of the extended psu(2,2|4) under the Penrose limit to obtain the most general consistent extension of the plane-wave superalgebra and compare these extensions with the possible BPS (flat or spherical) brane configurations in the plane-wave background. We give an explicit realization of some of these extensions in terms of the Tiny Graviton Matrix Theory (TGMT)[hep-th/0406214] which is the 0+1 dimensional gauge theory conjectured to describe the DLCQ of strings on the AdS_5 x S^5 and/or the plane-wave background.Comment: 27 pages, LaTe

Electrified BPS Giants: BPS configurations on Giant Gravitons with Static Electric Field

We consider D3-brane action in the maximally supersymmetric type IIB plane-wave background. Upon fixing the light-cone gauge, we obtain the light-cone Hamiltonian which is manifestly supersymmetric. The 1/2 BPS solutions of this theory (solutions which preserve 16 supercharges) are either of the form of spherical three branes, the giant gravitons, or zero size point like branes. We then construct specific classes of 1/4 BPS solutions of this theory in which static electric field on the brane is turned on. These solutions are deformations about either of the two 1/2 BPS solutions. In particular, we study in some detail 1/4 BPS configurations with electric dipole on the three sphere giant, i.e. BIons on the giant gravitons, which we hence call BIGGons. We also study BPS configurations corresponding to turning on a background uniform constant electric field. As a result of this background electric field the three sphere giant is deformed to squashed sphere, while the zero size point like branes turn into circular or straight fundamental strings in the plane-wave background, with their tension equal to the background electric field.Comment: 32 pages, 1 eps figure; v2: Presentation of derivation of light-cone Hamiltonian improved, Refs adde

Study On Social Support for Exercise And Its Impact on the Level of Physical Activity of Patients with Type 2 Diabetes

BACKGROUND: Physical activity is one of the most important self-care approaches to controlling complications of type 2 diabetes. According to Bandura’s social theory, factors such as social support are effective factors in the incidence of the behaviour. AIM: This study aims to determine the level of physical activity, social support and their determinants. METHODS: This descriptive study was performed on 250 patients with type 2 diabetes by Cluster-Random Sampling method in Rafsanjan City. Data were collected using the International Physical Activity Questionnaire and Social Support Questionnaire for Sport, that their validity and reliability were confirmed. The results were analysed by t-test, ANOVA and logistic regression. RESULTS: This study showed that 46.8% of the patients were in the inactive group. Social support score for exercise was low in this group. The results indicated that social support and gender are predictors of physical activity, and with an increase in the social support score, the odds of having minimal physical activity increased 1.17 fold (OR = 1.167) and men were 4.18 times more likely to have minimal physical activity (OR = 4.183). CONCLUSION: Considering the low level of physical activity and social support in diabetic patients, and the effect of social support on the prediction of physical activity, interventions are recommended to increase social support in this group

The Predictive Effects of Protection Motivation Theory on Intention and Behaviour of Physical Activity in Patients with Type 2 Diabetes

INTRODUCTION: Theory-based education tailored to target behaviour and group can be effective in promoting physical activity.AIM: The purpose of this study was to examine the predictive power of Protection Motivation Theory on intent and behaviour of Physical Activity in Patients with Type 2 Diabetes.METHODS: This descriptive study was conducted on 250 patients in Rafsanjan, Iran. To examine the scores of protection motivation theory structures, a researcher-made questionnaire was used. Its validity and reliability were confirmed. The level of physical activity was also measured by the International Short - form Physical Activity Inventory. Its validity and reliability were also approved. Data were analysed by statistical tests including correlation coefficient, chi-square, logistic regression and linear regression.RESULTS: The results revealed that there was a significant correlation between all the protection motivation theory constructs and the intention to do physical activity. The results showed that the Theory structures were able to predict 60% of the variance of physical activity intention. The results of logistic regression demonstrated that increase in the score of physical activity intent and self - efficacy increased the chance of higher level of physical activity by 3.4 and 1.5 times, respectively OR = (3.39, 1.54).CONCLUSION: Considering the ability of protection motivation theory structures to explain the physical activity behaviour, interventional designs are suggested based on the structures of this theory, especially to improve self -efficacy as the most powerful factor in predicting physical activity intention and behaviour

Classification of All 1/2 BPS Solutions of the Tiny Graviton Matrix Theory

The tiny graviton matrix theory [hep-th/0406214] is proposed to describe DLCQ of type IIB string theory on the maximally supersymmetric plane-wave or AdS_5xS^5 background. In this paper we provide further evidence in support of the tiny graviton conjecture by focusing on the zero energy, half BPS configurations of this matrix theory and classify all of them. These vacua are generically of the form of various three sphere giant gravitons. We clarify the connection between our solutions and the half BPS configuration in N=4 SYM theory and their gravity duals. Moreover, using our half BPS solutions, we show how the tiny graviton Matrix theory and the mass deformed D=3, N=8 superconformal field theories are related to each other.Comment: 40 pages, 12 figures, v

Performing the Egyptian revolution : origins of collective restraint action in the Midan

This research was supported by a Carnegie Trust for the Universities of Scotland grant.In January/February 2011, the world watched with admiration the Egyptian revolution that toppled President Housni Mubarak. The demonstration in Midan al-Tahrir (Liberation Square in central Cairo), which was the nucleus of the revolution, highlighted a largely spontaneous, civil and peaceful political performance. However, this performance was temporary, contradicting subsequent bloody conflicts in post-revolutionary Egypt. This article examines the socio-political origins of the Midan performance. It argues that the demonstrators exercised collective restraint, which was temporary but necessary, in order to topple Mubarak. Building on Norbert Elias’ civilising process theory and social movements literature, it is argued that the origins of this performance are found in a collective knowledge of regime strategy and narrative, Egyptian socio-political values and existing repertoires of contention. Drawing on primary sources and semi-structured interviews, the article contends that the demonstrators exercised collective restraint to reframe regime narrative and draw public support for the revolution.PostprintPeer reviewe