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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Spatiotemporal Consciousness in Special Relativity / Spatiotemporal Medvetande i Speciell Relativitet

Malmberg, Gustaf January 2023 (has links)
The experience of time passing is a fundamental part of the human experience, but what is the relationship between conscious experiences in time and the relativistic nature of space and time? It is natural to think that our phenomenal experiences are realised by neuralevents in our brains. And it seems plausible that the order of these neural events makes a difference to our phenomenology. Yet, relativity theory entails that in some cases these neural events lack objective temporal orders. Instead, their temporal order is different relative to different, equally valid frames of reference. How then is this relativity compatible that intuitively there is only a single, objective way in which things appear to us? This question is at the centre of this thesis. I will present the context of the debate within the theory of Special Relativity and how different problems seem to arise between consciousness and Special Relativity. I will then introduce some basic key concepts for understanding Special Relativity. After introducing the foundation of the problem and a specific formulation that provides the structure of the rest of the thesis, I will present four different possible solutions to the problems, analysing their strengths and weaknesses. Finally, I will use one of the proposed solutions, the objective objection, to argue that the problem never actually arises to begin with and that it is based on a misreading of Special Relativity. I also argue that the objective objection is much more general than its originator proposes. / Att uppleva att tiden går är en central del av våra medvetna upplevelser, men vad är relationen mellan medvetna upplevelser i tiden och den relativistiska rumtiden? Våra fenomenologiska upplevelser måste vara formade av den temporala ordningen av neurologiska händelser och olika ordningar bör då ge upphov till olika fenomenologiska upplevelser. Den speciella teorin om relativitet tillåter olika ordningar av neurologiska händelser men detta står i kontrast med det faktum att vi endast kan ha en fenomenologisk upplevelse. I denna uppsats kommer jag undersöka relationen mellan speciell relativitet och medvetandet och varför det verkar som om relativitetsteorin ger upphov till flera fenomenologiska upplevelser när vi bara upplever en. Jag kommer presentera speciell relativitet och dess kontext i debatten om medvetandet och tid samt även ett par problem som verkar dyka upp mellan medvetandet och speciell relativitet. Därefter kommer jag att introducera några nyckelbegrepp för att underlätta förståelsen av speciell relativitet. Efter attha lagt fram problemet som uppsatsen undersöker kommer jag presentera fyra möjliga lösningar som jag har identifierat och deras styrkor samt svagheter. Slutligen kommer jag diskutera den lösning som jag tycker är mest sannolik, vilket är den objektiva invändningen, men jag argumenterar även att invändningen är mycket mer generell än dess ursprungliga författare föreslår och att problemet med flera sekvenser av neurologiska händer endast uppstår på grund av en missuppfattning om speciell relativitet.
12

Relative Reality

Steinberg, Gary 02 August 2002 (has links)
No description available.
13

As estruturas necessárias à teoria da relatividade restrita : um estudo a partir da epistemologia genética /

Penteado, Marianna Loureiro. January 2018 (has links)
Orientador: Ricardo Pereira Tassinari / Banca: Osvaldo Frota Pessoa Júnior / Banca: Marcelo Carbone Carneiro / Resumo: Esta Pesquisa se insere na área de Epistemologia Genética. O objetivo geral desta Pesquisa é discutir as estruturas necessárias ao conhecimento da Teoria da Relatividade Restrita de Albert Einstein segundo o Modelo do Sistema de Esquema de Ações e Operações sobre Símbolos e Signos (MoSEAOSS), um modelo baseado na Epistemologia Genética de Jean Piaget. Com vista a esse objetivo, são objetivos específicos desta Pesquisa: discutir os fenômenos da dilatação dos tempos e da contração dos comprimentos consequentes dos postulados da Teoria da Relatividade Restrita, assim como o Paradoxo dos Gêmeos, e, com base neles, analisar a noção de espaço-tempo que deles resultam; apresentar o MoSEAOSS, assim como os principais conceitos nele envolvidos, em especial, os conceitos de transfiguração e de transignação; aplicar o MoSEAOSS à Teoria da Relatividade Restrita e mostrar que a noção de espaço-tempo pode ser explicada por meio de operações que o sujeito realiza sobre símbolos e signos. / Abstract: This research is in the area of Genetic Epistemology. The overall goal of this research is to discuss the necessary structures for knowing Albert Einstein's Special Theory of Relativity according to the Model of the System of Schemes of Actions and Operations on Symbols and Signs (MoSEAOSS), a model based on Jean Piaget's Genetic Epistemology. The specific objectives of this research are: to discuss the phenomena of Time Dilation and Length Contraction that follow the postulates of Special Theory of Relativity, as well as the Twin Paradox, and, based on them, to analyze the notion of space-time that results from them; to introduce the MoSEAOSS, as well as the key concepts involved in it, especially, the concepts of transfiguration and transignation; to apply the MoSEAOSS to Special Theory of Relativity and to show that the notion of space-time can be explained by means of operations that the subject performs on symbols and signs. / Mestre
14

Quantum Field Theory: Motivating the Axiom of Microcausality

Wright, Jessey January 2012 (has links)
Axiomatic quantum field theory is one approach to the project of merging the special theory of relativity with that of ordinary quantum mechanics. The project begins with the postulation of a set of axioms. Axioms should be motivated by reasonable physical principles in a way that illustrates how a given axiom is true. Motivations are often grounded in the principles of the parent theories: ordinary quantum mechanics or the theory of special relativity. Amongst the set of axioms first proposed by Haag and Kastler in 1963 is the axiom of microcausality. Microcausality requires the observables of regions at space-like separation to commute. This thesis seeks to answer the question ‘What principles from the special theory of relativity or ordinary quantum mechanics motivate, or justify, accepting microcausality as an axiom?’ The first chapter will provide the necessary background to investigate this question and the second chapter will undertake that investigation. In conclusion, microcausality cannot be well-motivated by individual principles rooted in the special theory of relativity or ordinary quantum mechanics.
15

Computer aided instruction of special relativity

Lin, Yinghua January 1991 (has links)
This thesis creates an small expert system that is based on Einstein's special relativity. The basic knowledge of special relativity and the bases for building an expert system are described. The concepts of special relativity are put into a knowledge base by changing the formulas into rules and facts. The Prolog language was used to develop the expert system. New information can be input that does not contradict the rules and facts already in the database. The system also uses computer graphics to demonstrate the physical concepts of relativity. By using this expert system, one can teach the basic knowledge of special relativity and solve some problems related to frames of reference moving with high speed. / Department of Computer Science
16

Quantum Field Theory: Motivating the Axiom of Microcausality

Wright, Jessey January 2012 (has links)
Axiomatic quantum field theory is one approach to the project of merging the special theory of relativity with that of ordinary quantum mechanics. The project begins with the postulation of a set of axioms. Axioms should be motivated by reasonable physical principles in a way that illustrates how a given axiom is true. Motivations are often grounded in the principles of the parent theories: ordinary quantum mechanics or the theory of special relativity. Amongst the set of axioms first proposed by Haag and Kastler in 1963 is the axiom of microcausality. Microcausality requires the observables of regions at space-like separation to commute. This thesis seeks to answer the question ‘What principles from the special theory of relativity or ordinary quantum mechanics motivate, or justify, accepting microcausality as an axiom?’ The first chapter will provide the necessary background to investigate this question and the second chapter will undertake that investigation. In conclusion, microcausality cannot be well-motivated by individual principles rooted in the special theory of relativity or ordinary quantum mechanics.
17

Caos quântico relativístico / Relativistic quantum chaos

Pinto, Rafael Soares, 1986- 05 May 2011 (has links)
Orientadores: Patrício Aníbal Letelier Sotomayor, Marcus Aloízio Martinez de Aguiar / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin / Made available in DSpace on 2018-08-17T22:28:47Z (GMT). No. of bitstreams: 1 Pinto_RafaelSoares_M.pdf: 2173613 bytes, checksum: 878c544ecf4ce79eb9b5b0be033ad255 (MD5) Previous issue date: 2011 / Resumo: Nesta dissertação analisamos bilhares usando a teoria da relatividade especial, tanto classicamente quanto quanticamente. Inicialmente revisamos a teoria de bilhares clássicos, com ênfase em como se dá sua evolução no tempo. Então estudamos a existência (ou não) de aceleração de Fermi em bilhares forçados: bilhares onde a parede se move e, quando a partícula colide, ela pode ganhar ou perder energia. Estudamos alguns exemplos de bilhares, regulares e caóticos, na dinâmica relativística procurando quais condições são necessárias para que exista aceleração de Fermi relativística Concentramos-nos então no estudo de bilhares quânticos. Após uma revisão dos conceitos básicos, estudamos o método da integral de contorno para o cálculo do espectro do bilhar e analisamos suas propriedades estatísticas, tanto para o caso não relativístico (a equação de Schroedinger) quanto para o caso relativístico, o bilhar de Dirac, introduzido por Berry e Mondragon / Abstract: In this dissertation we analyze billiards using the theory of special relativity, both in the classical and quantum versions. First we review classical billiards, with emphasis in its time evolution. Then we study the existence (or lack of) Fermi acceleration in driven billiards, billiards where the walls are moving and, when the particle collides, it can gain or lose energy. We studied some examples, regular and chaotic ones, in the relativistic dynamics, and analyzed the necessary conditions for the existence of relativistic Fermi acceleration. We focus then on quantum billiards. After a brief review of basic concepts, we study the boundary integral method for numerical evaluation of the billiard spectra and analyze its statistical properties, for the non-relativistic case (the Schroedinger equation) and the relativistic, the Dirac billiards introduced by Berry and Mondragon / Mestrado / Física Geral / Mestre em Física
18

Órbitas de partículas clássicas em teorias de campos de gauge / Classical particles orbits in gauge field theories

Fernandes, Rafael Monteiro 18 February 2005 (has links)
Orientador: Patricio Anibal Letelier Sotomayor / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Fisica Gleb Wataghin / Made available in DSpace on 2018-08-04T20:14:31Z (GMT). No. of bitstreams: 1 Fernandes_RafaelMonteiro_M.pdf: 6930880 bytes, checksum: bc2d3294a7be01c0e28037221d2d4b4d (MD5) Previous issue date: 2005 / Resumo: Não informado / Abstract: Not informed. / Mestrado / Física das Particulas Elementares e Campos / Mestre em Física
19

Elektromagnetické vlny v disperzních a refraktivních relativistických systémech / Electromagnetic Waves in Dispersiveand Refractive Relativistic Systems

Bezděková, Barbora January 2019 (has links)
Study of light rays (light world lines) plays a significant role in many of astro- physical applications. Light rays are mainly studied in terms of so-called grav- itational lensing. However, the majority of studies are mainly focused on light propagation in vacuum. If the refractive and dispersive medium characterised by refractive index n is considered, effects occurring due to the medium presence need to be taken into account, which significantly complicates the problem. In the present thesis, rays propagating through simple refractive and dispersive systems, such as plane differentially sheared medium, are studied. In order to simplify the problem, the Hamiltonian equations of motion are used. The ray trajectories in the vicinity of Kerr black hole as well as accessible regions for the rays are also studied. Radial variation of the medium velocity is considered. Due to the recent increase of publications focused on the gravitational lensing in plasma, a detailed review summarizing the results obtained recently is included. 1
20

Topics In Noncommutative Gauge Theories And Deformed Relativistic Theories

Chandra, Nitin 07 1900 (has links) (PDF)
There is a growing consensus among physicists that the classical notion of spacetime has to be drastically revised in order to nd a consistent formulation of quantum mechanics and gravity. One such nontrivial attempt comprises of replacing functions of continuous spacetime coordinates with functions over noncommutative algebra. Dynamics on such noncommutative spacetimes (noncommutative theories) are of great interest for a variety of reasons among the physicists. Additionally arguments combining quantum uncertain-ties with classical gravity provide an alternative motivation for their study, and it is hoped that these theories can provide a self-consistent deformation of ordinary quantum field theories at small distances, yielding non-locality, or create a framework for finite truncation of quantum field theories while preserving symmetries. In this thesis we study the gauge theories on noncommutative Moyal space. We nd new static solitons and instantons in terms of the so-called generalized Bose operators (GBO). GBOs are constructed to describe reducible representation of the oscillator algebra. They create/annihilate k-quanta, k being a positive integer. We start with giving an alternative description to the already found static magnetic flux tube solutions of the noncommutative gauge theories in terms of GBOs. The Nielsen-Olesen vortex solutions found in terms of these operators also reduce to the ones known in the literature. On the other hand, we nd a class of new instanton solutions which are unitarily inequivalent to the ones found from ADHM construction on noncommutative space. The charge of the instanton has a description in terms of the index representing the reducibility of the Fock space representation, i.e., k. After studying the static soliton solutions in noncommutative Minkowski space and the instanton solutions in noncommutative Euclidean space we go on to study the implications of the time-space noncommutativity in Minkowski space. To understand it properly we study the time-dependent transitions of a forced harmonic oscillator in noncommutative 1+1 dimensional spacetime. We also provide an interpretation of our results in the context of non-linear quantum optics. We then shift to the so-called DSR theories which are related to a different kind of noncommutative ( -Minkowski) space. DSR (Doubly/Deformed Special Relativity) aims to search for an alternate relativistic theory which keeps a length/energy scale (the Planck scale) and a velocity scale (the speed of light scale) invariant. We study thermodynamics of an ideal gas in such a scenario. In first chapter we introduce the subjects of the noncommutative quantum theories and the DSR. Chapter 2 starts with describing the GBOs. They correspond to reducible representations of the harmonic oscillator algebra. We demonstrate their relevance in the construction of topologically non-trivial solutions in noncommutative gauge theories, focusing our attention to flux tubes, vortices, and instantons. Our method provides a simple new relation between the topological charge and the number of times the basic irreducible representation occurs in the reducible representation underlying the GBO. When used in conjunction with the noncommutative ADHM construction, we nd that these new instantons are in general not unitarily equivalent to the ones currently known in literature. Chapter 3 studies the time dependent transitions of quantum forced harmonic oscillator (QFHO) in noncommutative R1;1 perturbatively to linear order in the noncommutativity . We show that the Poisson distribution gets modified, and that the vacuum state evolves into a \squeezed" state rather than a coherent state. The time evolutions of un-certainties in position and momentum in vacuum are also studied and imply interesting consequences for modelling nonlinear phenomena in quantum optics. In chapter 4 we study thermodynamics of an ideal gas in Doubly Special Relativity. We obtain a series solution for the partition function and derive thermodynamic quantities. We observe that DSR thermodynamics is non-perturbative in the SR and massless limits. A stiffer equation of state is found. We conclude our results in the last chapter.

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