Dissertations / Theses on the topic 'Background Theory'
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1
Sanjay. "String theory in AdS3 background." Thesis, University of Oxford, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.393713.
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Jeschek, Claus. "Background geometries in string and M-theory." Diss., lmu, 2005. http://nbn-resolving.de/urn:nbn:de:bvb:19-46722.
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Malmros, Ingegärd Enander. "Optimal Foraging Theory - OFT : Background, Problems and Possibilities." Thesis, Högskolan på Gotland, Institutionen för kultur, energi och miljö, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:hgo:diva-1488.
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Optimal Foraging Theory (OFT) has its origin in processualistic ideas in 1960s with traces back to the dawn of the archaeological science in the 19th century. The OFT model is based on the construction of an individual’s food item selection understood as an evolutionary construct that maximizes the net energy gained per unit feeding time. The most common variants are diet patch choice, diet breadth/prey choice models and Marginal Value Theorem (MVT). The theory introduced experimental studies combined with mathematically data analyses and computer simulations. The results visualized in the experimental diagrammed curve are possible to compare with the archaeological records. What is “optimal” is an empirical question not possible to know but still useful as a benchmark for measuring culture. The theory is common in USA but still not in Europe. OFT seems to be useful in hunter-gatherer research looking at human decisions, energy flow, depression of resources and extinction. This literature review concludes that the prey-choice/diet-breadth model seems to be useful for hunter-gatherer research on Gotland focusing on possible causes of the hiatus in archaeological records between 5000-4500 BC.Optimal Foraging Theory (OFT) har sitt ursprung i de processualistiska ideérna under 1960-talet med spår tillbaka till arkeologins början som vetenskap under 1800-talet. OFT modellen baseras på konstruktionen av en individs födoämnesval som förstås som en evolutionär konstruktion som maximerar nettoenergiintaget per tidsenhet som gått åt för försörjningen. De vanligaste varianterna är patch-choice, diet breadth/prey choice modellerna och Marginal Value Theorem (MVT). Experimentella studier genomförs och data bearbetas matematiskt och visar datorsimulerade kurvdiagram möjliga att jämföra med arkeologiska källmaterial. Vad som är ”optimalt” är en empirisk fråga omöjlig att veta men användbar ändå som en slag referens för att mäta kultur. Teorin är vanlig i USA men ännu inte i Europa. OFT förefaller användbar inom forskning av jägare-samlare om man fokuserar på beslutsfattande, energiflöde, depression av resurser och utrotning av arter. Slutsatsen i denna litteraturöversikt är att prey choice/diet breadth modellen tycks vara användbar för gotländsk jägare-samlare-forskning som fokuserar på möjliga orsaker till de arkeologiska fyndens hiatus mellan 5000-4500 BC.
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Todd, Stephen Robert. "Superstrings on orbifolds with constant background fields." Thesis, Royal Holloway, University of London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321650.
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Gold, Benjamin Mark. "Cosmic acceleration and the theory of the microwave background /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2005. http://uclibs.org/PID/11984.
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Rätzel, Dennis. "Tensorial spacetime geometries and background-independent quantum field theory." Phd thesis, Universität Potsdam, 2013. http://opus.kobv.de/ubp/volltexte/2013/6573/.
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Famously, Einstein read off the geometry of spacetime from Maxwell's equations. Today, we take this geometry that serious that our fundamental theory of matter, the standard model of particle physics, is based on it. However, it seems that there is a gap in our understanding if it comes to the physics outside of the solar system. Independent surveys show that we need concepts like dark matter and dark energy to make our models fit with the observations. But these concepts do not fit in the standard model of particle physics. To overcome this problem, at least, we have to be open to matter fields with kinematics and dynamics beyond the standard model. But these matter fields might then very well correspond to different spacetime geometries. This is the basis of this thesis: it studies the underlying spacetime geometries and ventures into the quantization of those matter fields independently of any background geometry.
In the first part of this thesis, conditions are identified that a general tensorial geometry must fulfill to serve as a viable spacetime structure. Kinematics of massless and massive point particles on such geometries are introduced and the physical implications are investigated. Additionally, field equations for massive matter fields are constructed like for example a modified Dirac equation.
In the second part, a background independent formulation of quantum field theory, the general boundary formulation, is reviewed. The general boundary formulation is then applied to the Unruh effect as a testing ground and first attempts are made to quantize massive matter fields on tensorial spacetimes.Bekanntermaßen hat Albert Einstein die Geometrie der Raumzeit an den Maxwell-Gleichungen abgelesen. Heutzutage nehmen wie diese Geometrie so ernst, dass unsere fundamentale Materietheorie, das Standardmodell der Teilchenphysik, darauf beruht. Sobald es jedoch um die Physik außerhalb des Sonnensystems geht, scheinen einige Dinge unverstanden zu sein. Unabhängige Beobachtungsreihen zeigen, dass wir Konzepte wie dunkle Materie und dunkle Energie brauchen um unsere Modelle mit den Beobachtungen in Einklang zu bringen. Diese Konzepte passen aber nicht in das Standardmodell der Teilchenphysik. Um dieses Problem zu überwinden, müssen wir zumindest offen sein für Materiefelder mit Kinematiken und Dynamiken die über das Standardmodell hinaus gehen. Diese Materiefelder könnten dann aber auch durchaus zu anderen Raumzeitgeometrien gehören. Das ist die Grundlage dieser Arbeit: sie untersucht die zugehörigen Raumzeitgeometrien und beschäftigt sich mit der Quantisierung solcher Materiefelder unabhängig von jeder Hintergrundgeometrie. Im ersten Teil dieser Arbeit werden Bedingungen identifiziert, die eine allgemeine tensorielle Geometrie erfüllen muss um als sinnvolle Raumzeitgeometrie dienen zu können. Die Kinematik masseloser und massiver Punktteilchen auf solchen Raumzeitgeometrien werden eingeführt und die physikalischen Implikationen werden untersucht. Zusätzlich werden Feldgleichungen für massive Materiefelder konstruiert, wie zum Beispiel eine modifizierte Dirac-Gleichung. Im zweiten Teil wird eine hintergrundunabhängige Formulierung der Quantenfeldtheorie, die General Boundary Formulation, betrachtet. Die General Boundary Formulation wird dann auf den Unruh-Effekt angewendet und erste Versuche werden unternommen massive Materiefelder auf tensoriellen Raumzeiten zu quantisieren.
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Guglielmetti, Fabrizia. "Background-Source separation in astronomical images with Bayesian Probability Theory." Diss., lmu, 2010. http://nbn-resolving.de/urn:nbn:de:bvb:19-127320.
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Lee, Hok Kong Schwarz John H. "Gauge theory and supergravity duality in the pp-wave background /." Diss., Pasadena, Calif. : California Institute of Technology, 2005. http://resolver.caltech.edu/CaltechETD:etd-05262005-151056.
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Mau, Amelia. "Background Structures and Narrative in Music by Women." Thesis, University of Oregon, 2017. http://hdl.handle.net/1794/22697.
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This thesis explores the use of modified Schenkerian analysis and how it relates to a feminine narrative in a piece of music. In music theory literature about music by women, Schenkerian analysis is a tool that is often ignored; some scholars claim that the goal-oriented nature of Schenkerian analysis prevents it from being an effective tool to analyze music that doesn’t adhere to traditional tonal models, including modern works by women composers. In this study, it was found that modifying the Urlinie and Bassbrechung to reflect salience rather than a traditional harmonic structure allowed for the tool to actually reveal a lot about the underlying narratives in the music. The case studies include Genesis II (Janika Vandervelde), Missa Gaia; Mass for the Earth (Libby Larsen), and “Music Box” (Cynthia Folio).
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Pearson, Danielle K. "Effect of language background on metalinguistic awareness and theory of mind." Thesis, University of Stirling, 2013. http://hdl.handle.net/1893/20994.
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Research has shown that theory of mind tends to develop in typically-developing children at about the age of 4 years. However, language appears to play a great role in this, particularly as deaf children, particularly those born to hearing parents, display extreme delays in theory of mind development, while bilinguals have been found to develop at a somewhat faster rate than monolinguals. Additionally, effects of culture on theory of mind development remain somewhat unclear, as there have been mixed results in past research. Theory of mind has also been correlated with metalinguistic ability and executive functioning skills, leading to multiple hypotheses regarding what drives theory of mind development. The aim of this doctoral thesis was to examine the relationships between theory of mind, metalinguistic awareness, and executive functioning, as well as to evaluate how language and culture play a role in these relationships. Four studies were conducted in an attempt to seek answers to six research questions surrounding this aim. Study1 evaluated theory of mind, metalinguistic awareness, and executive functioning among hearing nursery children in Central Scotland. Study 2 was aimed at evaluating these same skills among deaf children in the U.S. and U.K., as well as developing a scaling of theory of mind abilities among deaf children. Study 3 assessed these skills among deaf Ghanaian children, as well as evaluating theory of mind abilities among a group of hearing Ghanaian children. Finally, Study 4 compared monolingual and bilingual children on theory of mind, metalinguistic awareness, and executive functioning. Results show that there is a strong link between theory of mind and metalinguistic awareness among hearing children that is not explained by executive functioning skills. This relationship was not apparent among deaf children, who struggle more with theory of mind than metalinguistic awareness. The deaf children in Ghana were delayed compared to their Western peers; hearing Ghanaian children were delayed compared to their Western peers as well, but only slightly. Bilingual children and monolingual children performed similarly on false belief and set-shifting tasks; however, monolingual children outperformed bilinguals on metalinguistic awareness and inhibition tasks, possibly due to low verbal mental age among the monolinguals. Results of the four studies suggest that language does play a part in the relationship between theory of mind and metalinguistic awareness. Due to limited data, cultural effects remain unclear. It is proposed that deaf children’s struggle with theory of mind stems from their difficulty with abstract concepts.
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Trocsanyi, Zoltan L. "Three-loop renormalization of Yang-Mills theory in background field gauge." Diss., Virginia Tech, 1990. http://hdl.handle.net/10919/39413.
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Bøhn, Olav Dybvik. "Ice abrasion of concrete, background theory and testing at the NTNU laboratory." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for konstruksjonsteknikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-19095.
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Ice abrasion has been reviewed. Concrete and ice and their most important properties in accordance to ice abrasion have been studied. Concrete strength and contact pressure between ice and concrete is found to be important factors. Former studies of ice abrasion differ in their conclusions of which parameters they include in their ice abrasion models. The different parameters are; ice contact pressure, ice sliding speed, temperature, concrete strength, size of aggregate, total sliding distance. Different models include one or more of these parameters. Some of the previous experiments has come to different conclusions, possible reasons for these differences has been discussed.A detailed description of the NTNU Ice Abrasion Laboratory is given. The abrasion test apparatus is based on the sliding contact abrasion test principle. A concrete specimen is mounted and an ice cylinder is slid on top of the concrete with applied pressure. Pressure, speed and temperature are all fully controllable to create different test scenarios. A custom made National Instruments LabView program is used to control, monitor and log the activities in the abrasion laboratory.Ice abrasion testing has been done at the NTNU Ice Abrasion Laboratory, investigating a possible difference in abrasion rate for identical concrete with unlike initial treatment. A total of four concretes sample were tested. All four of them were saturated after this saturation period 2 of them was abrasion tested directly and 2 of them were dried, resaturated and then abrasion tested. Abrasion results were distorted by cracking of the concrete samples. No conclusive data on the abrasion rate were obtained. Two possible reasons for cracking of the concrete samples were found. The concrete samples have not been stored in best possible way before testing, which may have caused them to weaken. Secondly the ice abrasion machine has a weakness somewhere under the concrete sample. Either the concrete bedding its bearings or the load sensors yields during testing allowing the concrete to tilt up and down as the ice moves back and forth. Tilting of the concrete sample creates a bigger strain for the concrete at the turning point of ice cylinder. Measurers to remove this problem are discussed.
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Lidstrom, Daniel. "Modular invariance of closed bosonic string theory with a pp-wave background." Thesis, University of British Columbia, 2010. http://hdl.handle.net/2429/29491.
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After a brief review of the necessary parts of the theory of the bosonic string, a consistent pp-wave background with constant dilaton and constant three-index antisymmetric field strength is introduced. In particular, the gravitational background is the plane wave with constant coefficients, and the antisymmetric field strength is chosen such that the worldsheet theory is both diff×Weyl invariant and stable. The one-loop closed bosonic string amplitude is evaluated and shown to be modular invariant. Then the free energy of a free closed string gas is calculated, modular invariance of it is proved, and the result is shown to be equivalent to the sum of free energies for the individual particle states.
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Kenton, Zachary. "Inflation : connecting theory with observables." Thesis, Queen Mary, University of London, 2017. http://qmro.qmul.ac.uk/xmlui/handle/123456789/25900.
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Information about the very early universe can be accessed from observations of the cosmic microwave background (CMB) radiation and the later formation of large-scale structure (LSS) that are produced from cosmological perturbations of the early universe. The most developed theoretical explanation for the origin of these perturbations is the theory of inflation, in which the early universe undergoes a period of accelerated expansion, amplifying quantum fluctuations to macroscopic size, which act as the seeds for the CMB anisotropies and the cosmic web of the LSS. The work in this thesis aims to connect the theory of inflation to properties of these observables in a highly detailed way, suitable for future high-precision astronomical surveys. After some introductory review chapters, we begin with new research on a study of inflation from string theory, deriving an observably-large value of the tensor-to-scalar ratio, which had been previously difficult to achieve theoretically. The next study investigates the link between the observed CMB power asymmetry and non-Gaussianity, including a novel non-zero value for the trispectrum. Next we study soft limits of non-Gaussian inflationary correlation functions, focussing first on the squeezed limit of the bispectrum and then generalizing to soft limits of higher-point correlation functions, giving results valid for multi-fi eld models of inflation.
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Dolby, C. E. "A state-space based approach to Quantum Field Theory in classical background fields." Thesis, University of Cambridge, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.598590.
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This dissertation is concerned with a new formulation of fermionic quantum field theory in classical (electromagnetic or gravitational) backgrounds, which uses methods analogous to those used in conventional multiparticle quantum mechanics. Emphasis is placed on the states of the system, described in terms of Slater determinants, rather than on the field operator, ψ(x). The vacuum state 'at time τ', defined as the Slater determinant of a basis for the span of the negative spectrum of the 'first quantized' Hamiltonian H1 (τ), provides a concrete realisation of the Dirac Sea. By using the concept of 'radar time', I propose a generalisation of the concept of 'hypersurface of simultaneity', which can be applied to an arbitrarily moving observer in curved spacetime. This is used to provide a consistent particle interpretation for this observer, which depends only on the choice of observer and the background present, not on the choice of coordinates, the choice of gauge (in electromagnetic backgrounds) or the detailed construction of the observer's particle detector. It is also the first definition that does not rely on the spacetime possessing any convenient symmetries. I show that in the cases of a uniformly accelerating observer in flat space (Unruh effect), and a comoving observer in an exponentially inflating universe, my definition reduces to previously accepted definitions. Although this definition is necessarily non-local (no local definition of particle could possibly be consistent with the Unruh effect) I demonstrate with a simple example that this non-locality is only significant on scales of the order of the Compton wavelength λc = h/mc of the particle concerned. The general S-matrix element of the theory is derived in terms of time-dependent Bogoliubov coefficients, demonstrating that this follows directly from the definition of inner product between Slater determinants. The process of 'Hermitian extension', inherited directly from conventional multiparticle quantum mechanics, allows second quantized operators to be defined without appealing to a complete set of orthonormal modes, and provides an extremely straightforward derivation of the general expectation value of the theory. Applications of the formalism to pair creation in spatially uniform electric fields, and to the treatment of discrete symmetries, are presented.
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Aguiar, Aline. "Examining how post-secondary L2 readers make use of background knowledge when reading literary texts an exploratory study." Mémoire, Université de Sherbrooke, 2011. http://hdl.handle.net/11143/5645.
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Literary texts offer rich opportunities for language learning. However, can second language (L2) learners fully understand L2 literary texts? According to Bernhardt (2001):"the act of reading in a second language is extremely tricky -- is even trickier with literary texts that are inherently ambiguous, full of metaphor and intertextual relations to texts to which the readers have no access" (p.198). In other words, L2 readers are often poorly equipped grammatically, linguistically and culturally to cope with literary texts in which it might be difficult to recognize figurative language, to comprehend metaphors, to identify underlying cultural assumptions and above all to think critically while navigating those complexities. Therefore, during the reading process, L2 readers encounter gaps in the text which necessarily compel them to use whatever background knowledge they possess in order to create meaning. The purpose of this research is to see exactly how post-secondary L2 readers use their existing background knowledge to understand literary texts and what they do when confronted with text passages for which they lack such knowledge.
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McLaughlin, John Gerard. "Renormalisation of the energy-momentum stress tensor for quantum fields on a curved background." Thesis, University of Oxford, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.276530.
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Bowers, Mark. "Young people and problem drug use : the role of attachment theory and family background." Thesis, University of Leicester, 2000. http://hdl.handle.net/2381/31292.
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Attachment theory has been proposed as a potential framework from which to understand the variable effect of family of origin experiences on the problematic use of drugs in young people. The present study measured family experiences, attachment styles, hopelessness and drug use, drawing participants from both a drug treatment service and the general population of young people. The findings indicated that the young people with drug use problems differed from the control group in that they emphasised the positive consequences of drug use and were more likely to leave school early. Furthermore, aspects of the family experience, close relationships, and attachment anxiety were associated with higher levels of drug use. However, there was an absence of a direct relationship between family of origin experiences and attachment style. The number of close relationships the young person had experienced was directly related to higher levels of drug use, greater attachment anxiety and particular family experiences. It was concluded that, although attachment theory appears to be a promising framework from which to approach the influence of the family on subsequent drug use, the current research failed to identify a direct link between family experiences and measured attachment style. However, the role of romantic relationships appeared to be crucial for young people as they endeavour to create a secure close relationship. Lack of success in this domain of life may be viewed as either, a cause or a side effect of increased use of drugs. It is proposed that, irrespective of the causal instigator, poorer relationships and high levels of drug use will have an interacting effect. Therefore, close relationships are regarded as a legitimate target for therapeutic intervention when addressing the treatment needs of young people with drug use problems.
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Rätzel, Dennis [Verfasser], and Martin [Akademischer Betreuer] Wilkens. "Tensorial spacetime geometries and background-independent quantum field theory / Dennis Rätzel. Betreuer: Martin Wilkens." Potsdam : Universitätsbibliothek der Universität Potsdam, 2013. http://d-nb.info/103654673X/34.
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Forgues, Francois. "Higher-Order Moment Models for Multiphase Flows Coupled to a Background Gas." Thesis, Université d'Ottawa / University of Ottawa, 2019. http://hdl.handle.net/10393/39098.
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Modelling of laminar multiphase flow is extremely important in a wide range of engineering and scientific applications. The particle phases are often difficult to model, especially when particles display a range of sizes and velocities at each location in space. Lagrangian methods can be too expensive and many Eulerian methods, though often computationally more affordable, suffer from model deficiencies and mathematical artifacts that lead to non-physical results. For example, efficient Eulerian models that can accurately predict the crossing of multiple streams of non-interacting particles in laminar flow have traditionally been lacking. The predictive capabilities of modern techniques from the kinetic theory of gases to the treatment of disperse multiphase flows are investigated. In particular, several moment-methods, including a recently proposed fourteen-moment approximation to the underlying kinetic equation describing particle motion, are considered and their abilities to predict particle-stream
crossing are assessed. Furthermore, a new polydisperse model has been proposed for treatment of flows that display a range of particles sizes. The proposed model is an extension of the well-known maximum-entropy ten-moment model from rarefied gas dynamics with an addition for the treatment of a range of particle diameters. This
model allows for anisotropic variance of particle velocities in phase space and directly treats correlations between particle diameter and velocity. The derivation and mathematical structure, of the proposed models are presented. A fine-volume discretization solution procedure for the resulting moment equations is described and
used for performing numerical experiments. Results for flow problems that are designed to demonstrate the fundamental behaviour of each model are presented. It is shown that the new models offer clear advantages in terms of accuracy as compared to traditional Eulerian models for multiphase flows.
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Adams, Julie. "Background and Leadership Traits to Effectively Lead Faculty Senates in California Community Colleges." Thesis, Walden University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3622969.
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Although the major responsibility for community college governance falls to presidents and administrators, researchers have recognized the integral role of faculty in governing higher education institutions. Few studies, however, have explored the effectiveness of contributions of faculty elected to community college academic senates. The purpose of this research was to investigate the background traits and leadership skills of elected academic senate presidents in order to identify both their perceptions of themselves as leaders and the perceptions of other faculty senate members. This study was based in the theory of transformational leadership in organizations and its impact on the effectiveness of organizations. The research question for this quantitative study focused on the extent to which the elected academic senate presidents' background and leadership traits affect the performance of faculty senates. The Multifactor Leadership Questionnaire (Form 5X; MLQ 5X) and supplemental demographic data were used with faculty at the 112 community colleges in a western state to measure the relationship between leadership behavior and organizational effectiveness. Data were analyzed using Pearson's correlation and z and t tests. Results indicated that there is a significant relationship between senate presidents who were transformational leaders and more effective in leading faculty senates. The implications for social change include informing community college faculty senates and their presidents about effective leadership styles and skills and providing resources to improve faculty governance. The anticipated results are improved college governance, enhanced college service to their communities, and enriched education for their students.
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Barnard, Roger Christopher Graham. "Non English speaking background learners in the mainstream classroom : a New Zealand case study." Thesis, University of Chichester, 2000. http://eprints.chi.ac.uk/936/.
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The introductory chapter of this thesis presents the central premise of the study - that classroom learning is constructed through talk - and states the primary aims. These are to provide an ethnographic account of the process of learning in a mainstream classroom, and to apply to this account a specific theoretical framework with a view to refining its central constructs. The thesis proceeds with a discussion of the methodological basis of the investigation - ethnographic case study - and the procedures used for data collection and analysis. This is followed by a discussion of the theoretical orientation of the study, which explains the complexity of the learning context of isolated bilingual schoolchildren and the rationale for a sociocultural approach to explore it. The neo-Vygotskian constructs central to this study - the zone of proximal development, scaffolding and appropriation - are introduced and explained, as are supporting concepts. Each of the three following chapters of the thesis is divided into three parts. The first examines in detail one of these constructs, and also related concepts, with a view to their potential relevance to the specific context of learning. The second part in each chapter comprises a detailed ethnographic description, micro genetic analysis and interpretation of the context and continuity of the learning discourse. The third part in each chapter comments on the implications for the constructs at issue. These three chapters constitute a narrative of the way that classroom learning is constructed through talk over a school year. The thesis concludes with a review of the pedagogical and theoretical implications arising from the investigation, and considers the utility of a neo-Vygotskian framework for further research into classroom learning.
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Huamán, René Negrón. "Uma introdução a supercordas em plano e AdS 5 XS 5 background." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-19112014-130002/.
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Apresentamos uma revisão dos elementos básicos do estudo da teoria clássica das supercordas em backgrounds planos e curvos, dando ênfase ao caso importante em que o background e a variedade AdS5 S5. Nós inclumos um estudo da corda bosonica para revisarmos alguns conceitos básicos da teoria de campos conforme em duas dimensões. Em seguida estudamos a teoria das supercordas em um espaço plano onde apresentamos uma introdução pedagógica ao formalismo de espinores puros. A ultima parte e dedicada a generalização da ação de Green-Schwarz para o caso de AdS5 S5 e uma apresentação do modelo sigma do formalismo de espinores puros no mesmo background.We present a review of the basic elements of the study of classical superstring theory in at and curved backgrounds, giving emphasis to the very important case of the AdS5S5 background. We include a study of the bosonic string to review some basic concepts of two dimensional conformal eld theory. We then move on to the superstring in at space where we present a pedagogical introduction to the pure spinor formalism of superstrings. The last part is devoted to the generalization of the Green-Schwarz action to AdS5 S5 and a presentation of the pure spinor sigma model in the same background.
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Tynan, R. W. "Stocking limits for South Australian pastoral leases : historical background and relationship with modern ecological and management theory." Title page, contents and abstract only, 2000. http://web4.library.adelaide.edu.au/theses/09AS/09ast987.pdf.
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Adams, Julie. "Background and Leadership Traits to Effectively Lead Faculty Senates in California Community Colleges." ScholarWorks, 2011. https://scholarworks.waldenu.edu/dissertations/1136.
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Although the major responsibility for community college governance falls to presidents and administrators, researchers have recognized the integral role of faculty in governing higher education institutions. Few studies, however, have explored the effectiveness of contributions of faculty elected to community college academic senates. The purpose of this research was to investigate the background traits and leadership skills of elected academic senate presidents in order to identify both their perceptions of themselves as leaders and the perceptions of other faculty senate members. This study was based in the theory of transformational leadership in organizations and its impact on the effectiveness of organizations. The research question for this quantitative study focused on the extent to which the elected academic senate presidents' background and leadership traits affect the performance of faculty senates. The Multifactor Leadership Questionnaire (Form 5X; MLQ 5X) and supplemental demographic data were used with faculty at the 112 community colleges in a western state to measure the relationship between leadership behavior and organizational effectiveness. Data were analyzed using Pearson's correlation and z and t tests. Results indicated that there is a significant relationship between senate presidents who were transformational leaders and more effective in leading faculty senates. The implications for social change include informing community college faculty senates and their presidents about effective leadership styles and skills and providing resources to improve faculty governance. The anticipated results are improved college governance, enhanced college service to their communities, and enriched education for their students.
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Royle, Elizabeth. "A grounded theory study of attitudes towards mental illness and help-seeking amongst police officers with a military background." Thesis, University of Manchester, 2014. https://www.research.manchester.ac.uk/portal/en/theses/a-grounded-theory-study-of-attitudes-towards-mental-illness-and-helpseeking-amongst-police-officers-with-a-military-background(4b9973d5-25b0-427c-9005-f81b47b23387).html.
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Introduction: Both police and Armed Forces personnel are at increased risk of encountering psychological trauma with the prevalence of mental health problems higher than in the general population. Appropriate and effective mental health services are crucial but there is a marked lack of take-up of services. This research considered how the attitudes of police officers with a military background affected their help-seeking for mental health problems. Methodology: A phenomenological approach was used with the aims of producing rich data with the insider viewpoint and generating theory about the process. Semi-structured interviews were conducted with 11 male ex-Armed Forces police officers. A social constructivist Grounded Theory approach was used to analyse the data. Findings: Police officers with an Armed Forces background viewed themselves as a discrete social group. There was significant cognitive separation between them and their non-service peers, the police organisation, those with mental illness and mental health services. Four group norms, formed during military service, were identified as relevant to the research topic: a) Mission Focus, b) Strength and Control, c) Cohesion and d) Be the Best. These norms were used to determine the stigma associated with both on-set and off-set responsibility for mental health problems within the group. Group norms underpinned the acceptable strategies for managing mental health problems. Education around mental health was not seen as personally relevant at the time. Accepting a mental health problem was the greatest barrier to care and meant an acceptance of norm violation in oneself often triggering an existential crisis. Potential helpers were judged against the group norms and this either hindered or facilitated the process. As the individual recovered, they reframed the group norms in relation to their experience of mental illness and reported Post Traumatic Growth. A theoretical model for the help-seeking process is proposed. Implications: Anti-stigma interventionists need to consider the individual’s perception of their loss of a valued identity and their violation of group norms. The stereotyping and generalisation of police managers and mental health services as “other” reduces the likelihood of accepting offers of support from those sources. Education must connect with the early beliefs from military service in order to effect change. Organisational denial or ambivalence about the subject needs tackling just as much as the denial in the group and individuals. The group holds much of the solution to the problem within its own membership and peer supporters who have overcome their own mental health challenges can be better used by the organisation to both prevent and manage the problem. They need to able to provide timely, trusted referrals to competent mental health services.
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Lee, Hayden. "High-energy aspects of inflationary cosmology." Thesis, University of Cambridge, 2017. https://www.repository.cam.ac.uk/handle/1810/273359.
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Since the discovery of the cosmic microwave background (CMB), our understanding of the cosmos has been rapidly evolving. Detailed measurements of the CMB temperature fluctuations have led to a standard cosmological model, which traces the origin of the large-scale structure of the universe to quantum fluctuations during inflation. Although the basic framework of inflationary cosmology is now well-established, the microphysical mechanism responsible for the accelerated expansion remains a mystery. In this thesis, we describe how the physics underlying inflation can be probed using two cosmological observables: higher-order correlations of primordial density perturbations (non-Gaussianity) and primordial gravitational waves (tensor modes). In the first part of the thesis, we explore novel signatures of high-energy physics in higher- order correlation functions of inflationary perturbations. First, we use causality and unitarity to make connections between cosmological observations and the underlying short-distance dynamics of single-field inflation. We obtain a constraint on the size and the sign of the four-point function in terms of the amplitude of the three-point function. We then study the imprints of extra massive particles of arbitrary spin on the three-point function. We classify the couplings of these particles to inflationary scalar and tensor perturbations and derive explicit shape functions for their three- point functions that can serve as templates for future observational searches. Establishing the particle content during inflation would provide important hints for the microscopic theory of inflation. In the second part, we study ways of testing the nature of inflation using inflationary tensor modes. We consider effects of gravitational corrections to Einstein gravity in models of high-scale inflation. We show that these scenarios can lead to a violation of the tensor consistency condition (i.e. the relation between the amplitude and the scale-dependence of the tensor two-point function) that is satisfied by canonical single-field inflationary models. Finally, we consider the prospects for measuring the inflationary superhorizon signature in future observations. We define an estimator that captures superhorizon correlations and present forecasts for the detectability of the signal with future CMB polarization experiments.
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PIETROBON, DAVIDE. "Making the best of cosmological perturbations: theory and data analysis." Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2010. http://hdl.handle.net/2108/1197.
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Grazie a esperimenti estremamente raffinati, la cosmologia moderna si trova oggi in quella che puo' essere defi nita l' epoca della precisione. I
cosmologi dispongono di una grande quatita' di strumenti per testare il cosiddetto modello cosmologico di concordanza e vincolarne i principali parametri. In particolare, la radiazione cosmica di fondo (CMB) ha svolto, e svolge
tutt'oggi, un ruolo chiave in questo ambito. Numerose domande rimangono
tuttavia ancora in attesa di una risposta, in particolare quelle che riguardano la fisica dell'inflazione, che ha governato l'Universo nelle prime fasi di
evoluzione, e la natura dell' accelerazione dell' espansione dell'Universo, che e' stata osservata negli ultimi anni.
La mia attivita' di ricerca ha contribuito ad approfondire lo studio e la conoscenza su entrambe le tematiche, che sono state accomunate dallo sviluppo
e dall'utilizzo delle needlets - una nuova "frame" sulla sfera - per analizzare
la CMB. Con questo strumento, abbiamo misurato l'effetto Sachs-Wolfe integrato, correlando i dati di WMAP e NVSS, e caratterizzato le proprieta'
della dark energy, seguendo un approccio fenomenologico che si basa sull'approssimazione
di fl uido perfetto. Stimolati dai risultati ottenuti, abbiamo studiato in dettaglio un modello unifi cato per le componenti di dark energy e dark matter,
che fa uso di un'equazione di stato affi ne, e investigato i vincoli sui parametri
di questo modello provenienti da WMAP e SDSS.
Abbiamo quindi applicato le needlets ai dati di WMAP 5-anni allo scopo
di studiare la gaussianita' della distribuzione delle perturbazioni della CMB.
Ci siamo dapprima concentrati sulle mappe, rilevando la presenza di regioni anomale, localizzate nell' emisfero meridionale, e studiando l'effetto che
queste regioni hanno sullo spettro di potenza angolare. Successivamente, abbiamo misurato la funzione di correlazione a tre punti (bispettro) delle needlets caratterizzandola in termini della sua ampiezza complessiva, descritta dal parametro fNL, e secondo la geometria delle configurazioni triangolari che contribuiscono al segnale totale. Abbiamo misurato una significativa anomalia nelle confi gurazioni isosceli, nuovamente presente nell'emisfero
meridionale.
Infine, ci siamo concentrati sulla costruzione di un estimatore per il bispettro delle needlets, includendo l'effetto spurio che puo' essere introdotto
dalla presenza di eventuale segnale residuo, proveniente da sorgenti di natura prevalentemente Galattica.Cosmology has entered the precision epoch thanks to several very accurate experiments. Cosmologists now have access to an array of tools to test the cosmological concordance model and constrain its parameters; the Cosmic Microwave Background radiation (CMB), in particular, has been playing a crucial role in this ambition. Many questions remain nonetheless unanswered, especially concerning the physics of the early Universe, the infl ationary mechanism which set the initial conditions for the Universe expansion, and the nature of the late time acceleration of the Universe expansion. My research contributes to both of these sub jects, the common ground being the development of a statistical tool - needlets, a new "frame" on the sphere - to analyse the CMB. By means of needlets, we measure the Integrated Sachs Wolfe effect by cross-correlating WMAP and NVSS datasets and characterise dark energy properties using a phenomenological fluid model. Motivated by our findings, we study in detail a parameterisation of the dark components, dark matter and dark energy, which makes use of an affine equation of state, constraining the parameters of the model by combining WMAP and SDSS datasets. We apply needlets to the WMAP 5-year data release testing the Gaussianity of the CMB perturbations. Our approach is twofold: we first focus on the maps, detecting anomalous spots located in the southern hemisphere and check their effect on the angular power spectrum. We next measure the needlet three-point correlation function (bispectrum) and characterise it in terms of its overall amplitude, constraining the primordial fNL parameter, and considering its properties according to the geometry of the triangle configurations which contribute to the total power. We find a significant anomaly in the isosceles confi gurations, again in the southern hemisphere. Finally we focus on the construction of an optimal estimator for the (needlets) bispectrum, taking into account foreground residuals due mainly to Galactic emission.
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Robinson, Rosalie Ann. "Pathways in context: Background characteristics and demographics in student progression through higher education." Thesis, The University of Sydney, 2006. http://hdl.handle.net/2123/4999.
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This research develops a theory to explain the pathways taken by students through higher education in Australia. From a socio-ecological perspective, pathways are conceptualised as a diverse series of choices within learning contexts. In relation to Australian higher education, the model of pathways through undergraduate courses emphasises contexts in which personal and social factors contribute to the choices students make over time. A new method identifies and documents longitudinal pathways of progression through university degree courses. Higher education population data was examined over time to test the Pathways Theory of student progression. This unique detailed longitudinal approach documented all the pathway choices made by a cohort of students as they progressed in and out of their courses over time. Pathways were documented to the point of departure from a course and beyond, to include the extended pathways of students who returned to their courses following stop-outs and transfers. The results highlight the importance of a longitudinal approach in explaining pathways through specific course contexts. This research underlines the importance of considering context and diversity in student behaviours when using indicators of performance, retention and completion. Understanding the relationship between the personal and social characteristics of students and their specific learning contexts contributed to an understanding of the choice behaviour of students as they negotiated pathways through courses within the broader context of higher education. [Information on pages 271-275 has been removed from the digital version of this thesis for copyright reasons. The full print version of this thesis is available in The University of Sydney Library: Robinson, R. A. (2006). Pathways in Context: Background Characteristics and Demographics in Student Progression through Higher Education. PhD Thesis. The University of Sydney, Sydney.]
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Robinson, Rosalie Ann. "Pathways in context: Background characteristics and demographics in student progression through higher education." University of Sydney, 2006. http://hdl.handle.net/2123/4999.
Full textAbstract:
Doctor of Philosophy(PhD)This research develops a theory to explain the pathways taken by students through higher education in Australia. From a socio-ecological perspective, pathways are conceptualised as a diverse series of choices within learning contexts. In relation to Australian higher education, the model of pathways through undergraduate courses emphasises contexts in which personal and social factors contribute to the choices students make over time. A new method identifies and documents longitudinal pathways of progression through university degree courses. Higher education population data was examined over time to test the Pathways Theory of student progression. This unique detailed longitudinal approach documented all the pathway choices made by a cohort of students as they progressed in and out of their courses over time. Pathways were documented to the point of departure from a course and beyond, to include the extended pathways of students who returned to their courses following stop-outs and transfers. The results highlight the importance of a longitudinal approach in explaining pathways through specific course contexts. This research underlines the importance of considering context and diversity in student behaviours when using indicators of performance, retention and completion. Understanding the relationship between the personal and social characteristics of students and their specific learning contexts contributed to an understanding of the choice behaviour of students as they negotiated pathways through courses within the broader context of higher education. [Information on pages 271-275 has been removed from the digital version of this thesis for copyright reasons. The full print version of this thesis is available in The University of Sydney Library: Robinson, R. A. (2006). Pathways in Context: Background Characteristics and Demographics in Student Progression through Higher Education. PhD Thesis. The University of Sydney, Sydney.]
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Kim, Yang-Tae. "A holistic mission for the Korean Church : considered against the background of the 19th century western missionary movement in Korea." Thesis, University of Wales Trinity Saint David, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.683221.
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Sellerholm, Alexander. "Cosmological dark matter and the isotropic gamma-ray background measurements and upper limits /." Doctoral thesis, Stockholm : Department of Physics, Stockholm University, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-38900.
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Broccoli, Matteo. "On the trace anomaly of a Weyl fermion in a gauge background." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amslaurea.unibo.it/16408/.
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In this thesis we study the trace anomaly of a Weyl fermion in an abelian gauge background. We first introduce the topic of anomaly
in Quantum Fields Theory and provide case studies of a global and a gauge anomaly. Then, we review the lagrangians of the Weyl fermion and Dirac fermion, the models that are the focus of our chiral and trace anomaly computations. Since we evaluate the anomalies using Pauli-Villars (PV) regularization, we present different PV masses and discuss the classical symmetries they break. We identify the differential operators that enter our regularization schemes and we review the method that we use to evaluate anomalies: we read them from the path integral à la Fujikawa and compute them with heat kernel formulas. Then, we evaluate the chiral and trace anomaly of the models we are interested in. The chiral anomaly is well studied in the literature and we reproduce the standard result. The trace anomaly is our original result and, although the presence of the chiral anomaly implies a breakdown of gauge invariance, we find that the trace anomaly can be cast in a gauge invariant form.
The issue is analogous to the one recently discussed in the literature about a conjectured contribution of an odd-parity term to the trace anomaly of a Weyl fermion in curved backgrounds. With an abelian gauge background, this odd-parity term would be a Chern-Pontryagin density, that does not appear in our final results.
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Goodwin, Donald F. "SYMPHONY FOR WIND ORCHESTRA BY LUIS SERRANO ALARCÓN: BACKGROUND, ANALYSIS, AND CONDUCTOR’S GUIDE." UKnowledge, 2016. http://uknowledge.uky.edu/music_etds/55.
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Born in 1972, Luis Serrano Alarcón has in a very short period of time, established himself as one of Spain’s most prominent composers. His works are constantly being performed, not only in his home country, but throughout the world. While some of his compositions tend to retain the rhythmic, harmonic, and melodic style typical to Spanish music, many of the works sound as if they were borne more from the Viennese symphonic tradition, both during the time of Haydn and Beethoven, but also during the time of Arnold Schoenberg.
As a young boy Alarcón took up piano lessons with a local teacher by the name of Javier Barranco. Through him, Alarcón learned “the music for piano of the great masters of Classicism, Romanticism, and Spanish Nationalism.” In addition he began to study with two other teachers: Jose Cervera Collado and Jose Maria Cervara Lloret. With Collado, Alarcón studied conducting, and with Lloret he studied harmony. As a result of all of this training, Alarcón was drawn toward the symphonic music of the Classical and Romantic periods, especially gravitating toward the music of Beethoven and Brahms.
Alarcón’s compositional style has maintained a chameleon-like flexibility as he is able to change styles from one composition to the next with litheness and grace, showing a strong grasp of American jazz as well as flamenco music of his native country in Duende, capturing the sounds of tango from Argentina in Concertango, and of course, in the many examples of his paso dobles. Unlike many of his contemporaries, though, Alarcón’s unique voice seems to emerge through any style he is embracing or any combination of instruments in his orchestration.
In terms of style, Symphony for Wind Orchestra (2012) is an entirely different type of composition. It is immediately apparent from the opening tutti strikes, that (like Mozart and many other traditional composers before and after), Alarcón is embracing a iii traditional symphonic style in this composition by utilizing one of its most common symphonic topos. Symphony for Wind Orchestra is an amazing study of the Classical symphony from its earliest beginnings in Mannheim, to its codification at the hands of Haydn, Mozart, and Beethoven, and to its explosion in size and scope at the end of the nineteenth and early twentieth century with composers like Brahms, Bruckner, and Mahler. Perhaps more important, though, is his choice of harmonic language and compositional approach. The work is decidedly based upon thematic material that is reminiscent of the Second Viennese School; atonal at times, semi-tonal at others, but consistently manipulated through the operations (transposition, inversion, retrograde, verticalization, and serialization), that were made popular by Arnold Schoenberg, his students, and those who followed them.
The genesis of this composition was a consortium of band directors from the Southeastern Conference Band Association, led initially by Tom Verrier, who is Senior Band Conductor and Director of Wind Ensembles at Vanderbilt University. Dr. John Cody Birdwell was a part of the consortium from its onset, but didn’t initially plan on conducting the premiere at his school (the University of Kentucky). Birdwell stated,“...the opportunity to premiere the work sort of ‘landed in our lap.’ I had heard some of Alarcón’s other compositions in recent years, and I knew that this piece was going to be fantastic, so we moved forward without any hesitation.”
Clearly with so much positive feedback regarding the work, this document is certainly justified. The goals of this study are to provide some background for the work and its composer, to analyze the work while providing examples of all of its main themes and important figures, and where appropriate, to show how they relate to each other. This document will also create a helpful performance guide for conductors, which should facilitate and contribute to many more performances of this significant work in the future.
Along with the harmonic and thematic analysis of the work, this document will also include interviews with the composer, the conductor of the premiere of the work (Dr. John Cody Birdwell), one of the early and staunch supporters of Alarcón’s works (Dr. Tim Reynish), and Javier Enguidanos Morató - another Spanish conductor who recently performed the work.
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Emsley, Maletsema Ruth. "The effect of cultural background on comprehension of English texts by second language learners of English." Thesis, University of Limpopo, 2011. http://hdl.handle.net/10386/577.
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Thesis (M.Ed. (Language Education)) --University of Limpopo, 2011.This study investigated the effect of cultural background on comprehension of English texts by second language learners. The study specifically aimed at determining whether cultural background had any effect on comprehension of English texts by second language learners and whether the second language learners’ cultural background could help them comprehend unfamiliar texts. The background of the study in this mini dissertation was followed by the discussion on the literature available on this topic. This study followed a case study design which utilized 89 respondents from the Further Education and Training band of a rural secondary school in the north of Limpopo province. Data was obtained through the completion of questionnaires and answering of questions from a comprehension test based on English culture. The findings showed that there was no total comprehension of the text by learners who use English as a second language. Learners of English as a second language need to possess specific cultural schemata to comprehend texts that are unfamiliar to them. This study was informed by the schema theory. There is a significant effect of cultural background on the comprehension of English text by second language learners. KEY WORDS: Schema theory. Culture Comprehension. Cultural background
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Uddin, Rokon. "Explaining Adolescent Offending Variety in Sweden by Parental Country of Birth: A Test of Situational Action Theory." Thesis, Malmö högskola, Fakulteten för hälsa och samhälle (HS), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-26832.
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The main aim of this study is to explain adolescent offending variety by their parental country of birth. In doing so, the independent effect size and proportion of variance of two core elements of Situational Action Theory (SAT) – propensity and lifestyle risk – on offending variety are examined by immigrant background and gender. Although previous studies produced plenty of support to key assumption of SAT, no study so far measured offending variety as dependent variable. Analyses are based on self-reported data collected for Malmö Individual and Neighborhood Development Study (MINDS) during 2011-12, when the adolescent attained the age between 16 and 17. Ordinary least square (OLS) regression is run to examine the magnitude of effect and proportion of variance. Strong relation of offending variety separately with propensity and lifestyle risk was identified. Contrary to current scholarship on immigrant crime in Sweden, adolescent with immigrant parents are found at no more risk to engage in self-reported delinquency than the natives. Gender difference remains as a strong predictor of offending variety, especially for the immigrant group. This research reveals similarities in magnitude of effects of criminal propensity and lifestyle risks on offending variety, regardless of adolescents’ parental country of birth. Yet, propensity is a stronger predictor for delinquency variety than the lifestyle risks. This confirms applicability of the core elements of SAT, regardless of adolescents’ parental country of birth.
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Nazempooran, Ali. "The Effects of Cognitive Style and Socialization Background on Patterns of Behavior: Integrating Individual Differences (Using the MBTI) with Meadian Socialization Theory." Thesis, North Texas State University, 1988. https://digital.library.unt.edu/ark:/67531/metadc331932/.
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The general purpose of this study is to examine the effects of socialization background and cognitive style on individuals' patterns of behavior. The more specific purpose is to integrate the individual differences factor using the Myers-Briggs Type Indicator with Meadian Theory of Socialization in order to explore the ways in which a group of incarcerated individuals with prior felony and misdemeanor convictions and a group of college students are different regarding their different socialization background and cognitive styles. Data for this study were collected from a university and a county jail in Texas. During the process of data collection, two questionnaires consisting of 117 items were used to measure individual characteristics and elements of socialization background. This study is organized into four different chapters. Chapter I involves a detailed review of related literature, the purpose of the study, stated hypotheses, significance of the study, and limitations. Chapter II discusses methodological procedures and Chapter III presents the findings of the study. The last chapter includes a detailed conclusion and practical implications of the study. The findings in this study indicated that the group of incarcerated individuals and the group of college students are significantly different in terms of their different individual characteristics and socialization backgrounds. However, it was found that socialization background has the most significant effects on patterns of behavior among the two groups under study. It was concluded that while accepting the crucial importance of socialization factors, specific psychological characteristics of people also need to be integrated into sociological studies concerning human behavior for the better understanding of different groups and individuals in society.
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Pankiewicz, Ari. "Strings in plane wave backgrounds." Doctoral thesis, [S.l.] : [s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=968799981.
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Kujat, Jens. "Scalar fields in cosmology." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1142978764.
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Lozanov, Kaloian Dimitrov. "Expansion after inflation and reheating with a charged inflaton." Thesis, University of Cambridge, 2017. https://www.repository.cam.ac.uk/handle/1810/267822.
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Within the inflationary paradigm, our patch of the universe near the end of inflation is highly homogeneous and isotropic as necessitated by cosmic microwave background observations. This patch, however, is also in a cold and non-thermal state. A successful model of an inflationary primordial universe should account for how the universe transitioned from an inflationary to a radiation-dominated, hot, thermal phase required for the production of light elements via big-bang nucleosynthesis. It is desirable for such a model also to include a mechanism for the generation of the observed matter-antimatter asymmetry and perhaps a primordial mechanism for the generation of cosmic magnetic fields. The transition from an inflationary to a radiation-dominated, thermal phase (reheating) is likely to be phenomenologically rich. Reheating could include explosive particle production and various other non-perturbative, non-linear and non-equilibrium phenomena. Reheating can leave its own observational signatures in the form of gravitational waves and non-Gaussianities. Importantly, reheating can also affect the observational predictions of the preceding phase of inflation. Reheating remains an active field of research, with significant gaps in our understanding of the process. This thesis is an attempt to improve our understanding of the period following inflation, including reheating, through an exploration and analysis of realistic post-inflationary models with the aid of detailed numerical simulations. The focus of the studies is on aspects of the models with potential observational implications. In Part I of this thesis, we provide an overview of inflation and its end, concentrating on our current understanding of reheating and the challenges we face in trying to constrain reheating observationally. In Part II, we consider the post-inflationary expansion history in a broad class of observationally-favoured single-field models of inflation. Generally, the ambiguity in the expansion history of reheating can cause significant uncertainty in predictions for inflationary observables such as the spectral index, n_s, and the tensor-to-scalar ratio, r. The work in this part considers the full non-linear evolution of the inflaton during the initial stages of reheating and places bounds on the post-inflationary expansion history when perturbative couplings of the inflaton to other relativistic fields are included. In Part III, we investigate non-perturbative particle production and non-linear dynamics after inflation in models where the inflaton is charged under global/local symmetries. We first explore the effects of the non-linear inflaton dynamics for the generation of matter-antimatter asymmetry in the case where a global U(1) symmetry of the inflaton is weakly broken. We find a parameter range in which the model successfully predicts the observed baryon-to-photon ratio. We then consider the particle production during and after inflation in models with a charged inflaton under Abelian, U(1), and non-Abelian, SU(2) and U(1) x SU(2), gauge symmetries. Finally, we present a novel algorithm for evolving the full set of coupled, non-linear equations describing the U(1) charged inflaton and accompanying gauge fields on a lattice in an expanding universe. The novel feature here is that the gauge constraints are satisfied to machine precision when the gravitational dynamics are self-consistently included at the background level, and there are no restrictions on the order of the time-integrators.
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Siqueira, João Bosco de. "Limite de altas temperaturas em presença de campos externos estáticos." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-16102014-143540/.
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Investigamos certas propriedades físicas da teoria de campos a temperatura finita. Mostramos que, na presença de campos externos bosonicos, o limite de altas temperaturas das funções de Green pode ser obtido supondo que todas as componentes dos momentos externos sao nulas, para todas as funções de Green 1PI em ordem de um laco e em ordem de dois laços para a auto-energia. No contexto do método do campo de fundo, este resultado implica que a lagrangiana efetiva estática de um campo externo bosonico pode ser obtida calculando a pressão na presença de um campo externo independente do espaço-tempo, no limite de altas temperaturas. Aplicamos este resultado para obter a lagrangiana efetiva estática de um campo de Maxwell interagindo com um plasma da QED em ordem de dois laços. Obtivemos também a lagrangiana efetiva estática de um campo gravitacional interagindo com um campo escalar real livre, e com um plasma da QED em ordem de dois laços.We have investigated some physical proprieties of nite temperature field theory. We have shown that, in the presence of an external bosonic field, the high temperature limit of the static Green\'s functions can be obtained assuming that all components of the external momenta are zero. This was shown to be the case for all 1PI Green\'s functions, at one-loop order, as well as for the self-energy, at two-loop order. In the context of the background field method, this result implies that the static efective Lagrangian of an external field can be obtained computing the pressure in the presence of an external field which is independent of the space-time, in the high temperature limit. We have applied this result in order to obtain the efective Lagrangian of an external Maxwell field interacting with a QED plasma at two-loop order. We have also obtained the efective Lagrangian of the gravitational field interacting with a free neutral scalar field, as well as with a QED plasma at two-loop order.
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Iyescas, Kenneth Javier. "DUENDE: FOUR PRELUDES FOR SYMPHONIC WIND ENSEMBLE BY LUIS SERRANO ALARCÓN: CONDUCTOR’S GUIDE, SPANISH HISTORICAL BACKGROUND AND INFLUENCE." UKnowledge, 2017. http://uknowledge.uky.edu/music_etds/92.
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Luis Serrano Alarcón is one of the most important and relevant composers of our time. He is sought after as a composer, lecturer, and conductor throughout the world. His works have been performed in over 30 countries worldwide by some of the leading musical ensembles in the United States, Europe, and Asia, as well as being highly decorated by winning many prestigious composition contests including the International Band Competition Contest of Corciano, Italy.
Born in Valencia, Spain, Alarcón is relatively self-taught in composition, which is a testament to his natural-born gift for composition. His compositional output ranges from the traditional Spanish pasodoble to chamber music, solo pieces, and sophisticated masterpieces for orchestra and wind ensemble.
His work Duende: Four Preludes for Symphonic Wind Ensemble was commissioned by the University of St. Thomas Wind Ensemble, Minnesota (USA) in 2010. From its premiere, it became an extremely popular piece among wind band conductors. Duende’s appeal can be attributed to its fusion of Spanish popular music, the symphonic energy of Manuel de Falla’s scores, Iberia by the Spanish composer Isaac Albeniz, and the presence of jazz and Latin music.
A detailed conductor’s guide will be provided in this document that includes but not limited to an analysis of form and structure for each movement, conducting considerations, and rehearsal suggestions and techniques. Last but not least, an in-depth exploration into the composer’s background, Spanish musical influences, and the Spanish Band movement and traditions has been conducted. Through this process, an uncovering of intriguing and relevant points of interest have come to the surface. Alarcón’s music sounds the way it does and appeals to the masses because of the juxtaposition of its infectious, Spanish musical elements, as well as its traditional symphonic music components. Moreover, the long and historical past, culture, and traditions of Spanish Bands creates an enormous influence and motivation to compose for the wind band genre. More than two-thirds of all municipalities in Valencia, Spain have musical societies that serve as sponsors for the bands and other ensembles, provide music education, and function as a social center to the townspeople. They are also supported by the Valencian Federation of Musical Societies, all branches of government, the business community, and the media. The musical ensembles participate in both non-competitive and competitive performance activities. Non-competitive performances include concerts, wind band festivals, honor bands, and massed bands. Wind band competitions are sponsored at the municipal, provincial, regional, and international levels. Many of these performance types are combined for special celebrations like patron saint holidays, including Las Fallas and Moros y Cristianos.
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Snell, Brandon Charles. "The Origins of Ethno/National Separatist Terrorism: A Cross-National Analysis of the Background Conditions of Terrorist Campaigns." Wright State University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=wright1244481182.
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Choi, Jaewang. "Deformation of N=4 SYM with space-time dependent couplings." Kyoto University, 2018. http://hdl.handle.net/2433/232239.
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Parsian, Mohammadhadi. "Supersymmetric Backgrounds in string theory." Diss., Virginia Tech, 2020. http://hdl.handle.net/10919/97995.
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In the first part of this thesis, we investigate a way to find the complex structure moduli, for a given background of type IIB string theory in the presence of flux in special cases. We introduce a way to compute the complex structure and axion dilaton moduli explicitly. In the second part, we discuss $(0,2)$ supersymmetric versions of some recent exotic $mathcal{N}=(2,2)$ supersymmetric gauged linear sigma models, describing intersections of Grassmannians. In the next part, we consider mirror symmetry for certain gauge theories with gauge groups $F_4$, $E_6$, and $E_7$. In the last part of this thesis, we study whether certain branched-double-cover constructions in Landau-Ginzburg models can be extended to higher covers.Doctor of Philosophy
This thesis concerns string theory, a proposal for unification of general relativity and quantum field theory. In string theory, the building block of all the particles are strings, such that different vibrations of them generate particles. String theory predicts that spacetime is 10-dimensional. In string theorist's intuition, the extra six-dimensional internal space is so small that we haven't detected it yet. The physics that string theory predicts we should observe, is governed by the shape of this six-dimensional space called a `compactification manifold.' In particular, the possible ways in which this geometry can be deformed give rise to light degrees of freedom in the associated observable physical theory. In the first part of this thesis, we determine these degrees of freedom, called moduli, for a large class of solutions of the so-called type IIB string theory. In the second part, we focus on constructing such spaces explicitly. We also show that there can be different equivalent ways of constructing the same internal space. The third part of the thesis concerns mirror symmetry. Two compactification manifolds are called mirror to each other, when they both give the same four-dimensional effective theory. In this part, we describe the mirror of two-dimensional gauge theories with $F_4$, $E_6$, and $E_7$ gauge group, using the Gu-Sharpe proposal.
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Flachi, Antonino. "Quantum field theory on brane backgrounds." Thesis, University of Newcastle Upon Tyne, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366586.
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Tokunaga, Tatsuya. "String theory in Calabi-Yau backgrounds." 京都大学 (Kyoto University), 2008. http://hdl.handle.net/2433/136878.
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Bull, Philip J. "Dark energy and the inhomogeneous universe." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:8032ef45-5be2-451d-9cab-ebeccdf389f2.
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In this thesis, I study the relativistic effects of matter inhomogeneities on the accelerating expansion of the Universe. The acceleration is often taken to be caused by the presence of an exotic fluid called Dark Energy, or else a non-zero 'cosmological constant' term in the field equations of General Relativity. I consider whether this result could instead be an artefact caused by using an incorrect model to interpret observations. The standard 'concordance' cosmological model assumes the Cosmological Principle, which states that the matter distribution on large scales is homogeneous. One possibility is that correction terms appear in the field equations when small-scale inhomogeneities are smoothed over to produce this homogeneous model. These 'backreaction' effects could affect the dynamics of the spacetime, causing an apparent acceleration. I clarify the relationship between acceleration of the averaged spacetime and acceleration inferred from observable quantities, and show that they are closely related in statistically-homogeneous spacetimes. Another possibility is that the Universe could be inhomogeneous on large scales. If there was a large ‘void’, with us at the centre, the lensing of light by the void could reproduce the observations that imply cosmic acceleration. I show that a popular class of void models, based on spherically-symmetric Lemaitre-Tolman-Bondi spacetimes, are unable to simultaneously fit a selection of observational data, thus effectively ruling-out this possibility. These data include the Kinematic Sunyaev-Zel'dovich (KSZ) effect, which is a distortion/shift of the Cosmic Microwave Background (CMB) frequency spectrum caused by the Compton scattering of photons by hot gas in galaxy clusters. This, and other distortions of the CMB frequency spectrum, are sensitive to the degree of anisotropy in the CMB about a scattering cluster. I suggest tests involving these observables that exploit the strong link between isotropy and homogeneity to (a) distinguish between different causes of a deviation from spatial flatness on the horizon scale, and (b) potentially confirm the Cosmological Principle using observations. Finally, I describe a novel Bayesian CMB component separation method for extracting the Sunyaev-Zel'dovich signal of clusters from CMB sky maps.
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Masters, Kenneth Andrew. "Observing and describing textual "reality": a critique of the claims to objective reality and authentication in new critical and structuralist literary theory, seen against a background of Feyerabend's ideas concerning paradigms, dominance and ideology." Thesis, Rhodes University, 1992. http://hdl.handle.net/10962/d1002290.
Full textAbstract:
This thesis sets out to examine the claims to objective reality and authentication in New critical and Structuralist literary theories, concentrating on their claims to "objectivity" and "scientific validity." It examines the nature of these claims in the light of the original ideas proposed by some of the major New critics and structuralists in the development of their respective "sciences" of literary theory. Taking direction from the nature of reality and objectivity shown by the theorists, the thesis then attempts an assessment of the validity of some of the original perceptions and presuppositions concerning scientific objectivity and reality. It proposes that inconsistencies within the literary theories resulted from the theorists' inability to grasp the complexity and fluctuating nature of the borrowed terminology and principles that they were using. It does so by taking a closer look at the development of some of the more influential physical theories and the philosophical ideas raised by these developments. It then uses Feyerabend's work on paradigms, dominance and ideology to attempt an assessment of the reasons for the literary theorists' perceptions and presuppositions regarding objectivity and reality. This amounts to accounting for the specific scientific models chosen as bases, and also to accounting for the desire for the "scientific approach" at all. Its conclusions give an indication of the extent to which these original errors contributed to the theories' necessary adaptations of perspective and eventual loss of influence, and emphasises the need for the total understanding of concepts in one field by researchers in other fields, especially if those concepts are to be used by the researchers with any degree of precision.
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Mesquita, Daniel da Rosa. "Resolução de problemas relacionados à teoria de Grafos no Ensino Fundamental." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2015. http://hdl.handle.net/10183/132240.
Full textAbstract:
O objetivo desta dissertação é apresentar uma pesquisa e investigação que validam uma proposta de sequência didática que utiliza a perspectiva metodológica da Resolução de Problemas para ensinar conceitos relacionados à Teoria de Grafos na escola básica, mais especificamente, no Ensino Fundamental. Para tanto, a metodologia de pesquisa escolhida foi o Estudo de Caso, de acordo com Fiorentini e Lorenzato (2006), Ventura (2007) e Gil (1995). O referencial teórico é baseado nos trabalhos do GTERP1, de Onuchic e Allevato (1999) e (2004), Polya (2006), Pozo (1998), Santos (2002) e De Maio (2009), bem como os PCNs2 e outros artigos/livros relacionados à Teoria de Grafos e à Resolução de Problemas. Apresentaremos uma prática realizada com cinco grupos de uma turma do sétimo ano do Ensino Fundamental, em uma escola particular de Porto Alegre, no ano de 2014. Concluímos que a escolha desse tópico da Matemática aliado à perspectiva metodológica da Resolução de Problemas contribui para o desenvolvimento intelectual e matemático, bem como para a formação de um indivíduo mais autônomo e crítico.The aim of this dissertation is to show a research and investigation that validate a didactic propose of sequence that use the methodological perspective of Problem Solving to teach concepts related to Graph Theory in primary school, more specifically, in Elementary School. For this, the research methodology chosen was Case Study according to Fiorentini and Lorenzato (2006), Ventura (2007) and Gil (1995). The theoretical approach is based on the work of GETERP, Onuchic and Allevato (1999) and (2004), Polya (2006), Pozo (1998), Santos (2002) and De Maio (2009), as well as the National Curriculum Parameters (PCNs), books and articles dealing with Graph Theory and the Problem Solving. We will introduce a practice carried out with five groups of a class of seventh year of primary school, in a private school of Porto Alegre, in 2014. We conclude that the choice of this topic of mathematics combined with methodological perspective of Problem Solving contribute to the intellectual and mathematician development, as well as the formation of a more autonomous and critical individual.