Proton cyclotron echoes are phenomena related to the proton cyclotron frequency discovered On topside sounder swept-frequency ionograms from the Canadian satellite Alouette II in 1969. Subsequent studies were also limited to the use of the swept-frequency ionograms and devoted only to these so called regular proton cyclotron echoes. The regular proton cyclotron echoes occur on the swept-frequency ionograms at constant apparent ranges predominantly at frequencies below the electron plasma frequency fN and slightly above the electron cyclotron frequency fH. In this dissertation over 2000 topside sounder ionograms (both swept-frequency mode and fixed-frequency mode) obtained from the Alouette II, ISIS I and II satellites of the Alouette-ISIS program are used to investigate proton cyclotron echoes in detail. Examination of the combined swept-frequency and fixed ionograms indicates that the proton cyclotron echoes are also observed on the fixed-frequency ionograms, In addition to some features, such as constant apparent ranges and higher order multiple echoes, which have been already observed on the swept frequency ionograms and also occur on the fixed-frequency ionograms, under some Conditions non-constant apparent ranges and modulations in intensity of the proton cyclotron echoes on the fixed-frequency ionograms are observed. Usually the proton cyclotron echoes on the fixed-frequency ionogram can be observed for a much longer time than on the swept-frequency ionograms due to the fixed sounding frequencies. A proton cyclotron echo can be under observation for several spin periods of the satellite if the plasma parameters encountered by the sounder are appropriate, The modulation in intensity of the proton cyclotron echo by antenna orientation is evident. In terms of analysis of the combined swept-frequency and fixed-frequency ionograms, and the satellite orbital parameters and spin axis attitude, effects on proton cyclotron echoes of antenna orientation with respect to the earth’s magnetic field are examined. It is found that higher intensity and higher harmonics of proton cyclotron echoes occur when the sounding antenna is parallel to the earth’s magnetic field. A new class of proton cyclotron echoes was discovered, which occur on electron plasma resonances. The proton cyclotron echoes on the fH, nfH (n = 2, 3, 4), fQ3 and fD have been observed- The first three are checked in more detail. The proton cyclotron echoes observed on the fH, 4fH, fQ3 and fD resonances exhibit doublet, on the 2fH resonance triplex and on 3fH resonance single while the regular proton cyclotron echoes are always single. A frequency difference of about 5-10 Hz exists between subechoes in a doublet or triplex. The regular proton cyclotron echo seems to correspond to the first echo of the double or triple proton cyclotron echoes. No echo minus exists and most proton cyclotron echoes on the electron plasm a resonances are observed at dip angles whose magnitudes are less than 8°. This new class of proton cyclotron echoes is attributed to the results of nonlinear interactions of ion and electron Bernstein waves or ion Bernstein waves and DKO mode electromagnetic waves (for the fH resonance). Absorption phenomena on the 3fH, 4fH and fQ3 resonance spikes near the proton cyclotron period on swept-frequency ionograms are observed occasionally, but not yet understood. A theory based on nonlinear interaction of two waves is suggested to interpret proton cyclotron echoes. Many observational features of proton cyclotron echoes can be interpreted by this nonlinear interaction model of two waves. / Graduate

The study is focused on the thermal entanglement of spin chains. Chains consisting of two and three qubits are considered. These chains are considered open because they are coupled to bosonic baths at different temperatures. The baths represent the environment. The dynamics of these open systems are examined as are the effects of different parameters - such as bath temperature - on the entanglement of the spins. The measure of entanglement used in these cases is the concurrence. Comparisons are made between a model that assumes a strong spinspin interaction and one that assumes a weak one. In all these cases, analytical solutions for the system dynamics are presented. It is found that at large times, all systems converge to a state that depends only on bath temperature. It is also found that increases in bath temperatures diminish the entanglement between spins and that at high enough temperatures the entanglement vanishes altogether. The time and temperature dependence of the entanglement is different for the two models that are studied. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2010.

Nesta dissertação apresentamos o relato de uma proposta de inovação na abordagem da Física para o Curso Técnico em Radiologia Médica – Radiodiagnóstico, do Colégio Cenecista São Roque, localizado em Bento Gonçalves/RS. Motivados pela carência de trabalhos direcionados ao ensino técnico e pela necessidade em tratar a Física Moderna de modo mais conceitual, nos propusemos a elaborar uma página na internet como instrumento de apoio à disciplina de Proteção Radiológica. Considerando como marco teórico a teoria sóciointeracionista de Lev Semenovich Vygotsky e visando uma maior conscientização dos alunos quanto aos efeitos biológicos das radiações, adotamos como conceito central a dualidade onda-partícula. Tal referencial teórico considera como elemento fundamental para a aprendizagem a interação em sala de aula e dessa forma procuramos direcionar nossas aulas de modo a incentivar o debate. Os materiais didáticos desenvolvidos e adaptados para nossa prática constam de roteiros exploratórios, simulações computacionais de fenômenos físicos e leitura de textos de divulgação científica. Utilizando como ferramenta simuladores Java Applets disponíveis na internet, foram explorados os efeitos fotoelétrico e Compton. Através de um software educacional, desenvolvido no Instituto de Física, que simula o interferômetro de Mach-Zehnder abordamos o caráter dual das radiações. Este modo de abordar a Física despertou o interesse dos alunos levando-os a participar mais das aulas e a fazerem relações dos conteúdos estudados em sala de aula com os fenômenos físicos que regem o radiodiagnóstico. / In this dissertation we report an innovative approach in teaching Concepts of Quantum Physics to a technical level course in Medical Radiology, namely Radiodiagnostic at Colégio Cenecista São Roque in Bento Gonçalves/RS. The main reasons for this work are twofold: first, there is a small number of papers in the literature concerned to technical teaching and even less in this field specifically. Second, the students are required to get some conceptual understanding of Quantum Physics - an abstract subject most of them has never heard before. We have chosen the wave-particle duality as a central concept to introduce Quantum Physics given that analogies with classical wave mechanics could be more easily recovered. The dual character of electromagnetic radiation and the probabilistic nature of Quantum Physics were then emphasized since these concepts are fundamental for a better understanding of biological effects of radiation. It is also important to clarify Physics is part of our everyday and that even many of the norms that will rule their professional lives are based on the actual scientific knowledge. We believe better prepared technicians will be professionals more conscious of the importance of their own role in society. Working within Lev Semenovich Vygotsky framework we have fomented and motivated the learning through interaction among students in the classroom and through the debate among them. We have also elaborated a homepage during the semestre as a support tool to the discipline of Radiological Protection. Texts, interesting links, related news from newspaper have been continuously added as the students were suggesting or asking for. Besides the homepage, we have elaborated specific didactic material like exploratory scripts to guide the students through virtual simulations as for the Wave-particle duality in the Virtual Mach-Zehnder Interferometer and for the Photoelectric Effect. The students in general showed themselves very receptive to the innovations since they could be more active during the classes. Their final comments are interesting and they can give hints where this approach can be still improved and what they like it most.

Thesis (M.S.)--Miami University, Dept. of Physics, 2005. / Title from first page of PDF document. Document formatted into pages; contains [1], v, 296 p. : ill. Includes bibliographical references (p. 393-396).

Nesta dissertação apresentamos o relato de uma proposta de inovação na abordagem da Física para o Curso Técnico em Radiologia Médica – Radiodiagnóstico, do Colégio Cenecista São Roque, localizado em Bento Gonçalves/RS. Motivados pela carência de trabalhos direcionados ao ensino técnico e pela necessidade em tratar a Física Moderna de modo mais conceitual, nos propusemos a elaborar uma página na internet como instrumento de apoio à disciplina de Proteção Radiológica. Considerando como marco teórico a teoria sóciointeracionista de Lev Semenovich Vygotsky e visando uma maior conscientização dos alunos quanto aos efeitos biológicos das radiações, adotamos como conceito central a dualidade onda-partícula. Tal referencial teórico considera como elemento fundamental para a aprendizagem a interação em sala de aula e dessa forma procuramos direcionar nossas aulas de modo a incentivar o debate. Os materiais didáticos desenvolvidos e adaptados para nossa prática constam de roteiros exploratórios, simulações computacionais de fenômenos físicos e leitura de textos de divulgação científica. Utilizando como ferramenta simuladores Java Applets disponíveis na internet, foram explorados os efeitos fotoelétrico e Compton. Através de um software educacional, desenvolvido no Instituto de Física, que simula o interferômetro de Mach-Zehnder abordamos o caráter dual das radiações. Este modo de abordar a Física despertou o interesse dos alunos levando-os a participar mais das aulas e a fazerem relações dos conteúdos estudados em sala de aula com os fenômenos físicos que regem o radiodiagnóstico. / In this dissertation we report an innovative approach in teaching Concepts of Quantum Physics to a technical level course in Medical Radiology, namely Radiodiagnostic at Colégio Cenecista São Roque in Bento Gonçalves/RS. The main reasons for this work are twofold: first, there is a small number of papers in the literature concerned to technical teaching and even less in this field specifically. Second, the students are required to get some conceptual understanding of Quantum Physics - an abstract subject most of them has never heard before. We have chosen the wave-particle duality as a central concept to introduce Quantum Physics given that analogies with classical wave mechanics could be more easily recovered. The dual character of electromagnetic radiation and the probabilistic nature of Quantum Physics were then emphasized since these concepts are fundamental for a better understanding of biological effects of radiation. It is also important to clarify Physics is part of our everyday and that even many of the norms that will rule their professional lives are based on the actual scientific knowledge. We believe better prepared technicians will be professionals more conscious of the importance of their own role in society. Working within Lev Semenovich Vygotsky framework we have fomented and motivated the learning through interaction among students in the classroom and through the debate among them. We have also elaborated a homepage during the semestre as a support tool to the discipline of Radiological Protection. Texts, interesting links, related news from newspaper have been continuously added as the students were suggesting or asking for. Besides the homepage, we have elaborated specific didactic material like exploratory scripts to guide the students through virtual simulations as for the Wave-particle duality in the Virtual Mach-Zehnder Interferometer and for the Photoelectric Effect. The students in general showed themselves very receptive to the innovations since they could be more active during the classes. Their final comments are interesting and they can give hints where this approach can be still improved and what they like it most.

Nesta dissertação apresentamos o relato de uma proposta de inovação na abordagem da Física para o Curso Técnico em Radiologia Médica – Radiodiagnóstico, do Colégio Cenecista São Roque, localizado em Bento Gonçalves/RS. Motivados pela carência de trabalhos direcionados ao ensino técnico e pela necessidade em tratar a Física Moderna de modo mais conceitual, nos propusemos a elaborar uma página na internet como instrumento de apoio à disciplina de Proteção Radiológica. Considerando como marco teórico a teoria sóciointeracionista de Lev Semenovich Vygotsky e visando uma maior conscientização dos alunos quanto aos efeitos biológicos das radiações, adotamos como conceito central a dualidade onda-partícula. Tal referencial teórico considera como elemento fundamental para a aprendizagem a interação em sala de aula e dessa forma procuramos direcionar nossas aulas de modo a incentivar o debate. Os materiais didáticos desenvolvidos e adaptados para nossa prática constam de roteiros exploratórios, simulações computacionais de fenômenos físicos e leitura de textos de divulgação científica. Utilizando como ferramenta simuladores Java Applets disponíveis na internet, foram explorados os efeitos fotoelétrico e Compton. Através de um software educacional, desenvolvido no Instituto de Física, que simula o interferômetro de Mach-Zehnder abordamos o caráter dual das radiações. Este modo de abordar a Física despertou o interesse dos alunos levando-os a participar mais das aulas e a fazerem relações dos conteúdos estudados em sala de aula com os fenômenos físicos que regem o radiodiagnóstico. / In this dissertation we report an innovative approach in teaching Concepts of Quantum Physics to a technical level course in Medical Radiology, namely Radiodiagnostic at Colégio Cenecista São Roque in Bento Gonçalves/RS. The main reasons for this work are twofold: first, there is a small number of papers in the literature concerned to technical teaching and even less in this field specifically. Second, the students are required to get some conceptual understanding of Quantum Physics - an abstract subject most of them has never heard before. We have chosen the wave-particle duality as a central concept to introduce Quantum Physics given that analogies with classical wave mechanics could be more easily recovered. The dual character of electromagnetic radiation and the probabilistic nature of Quantum Physics were then emphasized since these concepts are fundamental for a better understanding of biological effects of radiation. It is also important to clarify Physics is part of our everyday and that even many of the norms that will rule their professional lives are based on the actual scientific knowledge. We believe better prepared technicians will be professionals more conscious of the importance of their own role in society. Working within Lev Semenovich Vygotsky framework we have fomented and motivated the learning through interaction among students in the classroom and through the debate among them. We have also elaborated a homepage during the semestre as a support tool to the discipline of Radiological Protection. Texts, interesting links, related news from newspaper have been continuously added as the students were suggesting or asking for. Besides the homepage, we have elaborated specific didactic material like exploratory scripts to guide the students through virtual simulations as for the Wave-particle duality in the Virtual Mach-Zehnder Interferometer and for the Photoelectric Effect. The students in general showed themselves very receptive to the innovations since they could be more active during the classes. Their final comments are interesting and they can give hints where this approach can be still improved and what they like it most.

Submitted by (lucia.rodrigues@ufrpe.br) on 2016-11-23T13:00:41Z No. of bitstreams: 1 Paulo Fernando Lima de Souza.pdf: 1161641 bytes, checksum: 9ee330df7fe48bfd1dc20c6a5b98183a (MD5) / Made available in DSpace on 2016-11-23T13:00:41Z (GMT). No. of bitstreams: 1 Paulo Fernando Lima de Souza.pdf: 1161641 bytes, checksum: 9ee330df7fe48bfd1dc20c6a5b98183a (MD5) Previous issue date: 2009-02-25 / The objective of this work was to investigate if transdisciplinarity can contribute to the understanding of the wave-particle duality principle. The investigation was conducted with students from the Physics teaching course at UFRPE. The methodology used was Kelly’s Experience Cycle, in which the objective was to involve the students in a learning process through three experiments: the wave tank; the Young experiment and Crookes’ radiometer. These three experiments motivated a discussion about wave-particle duality. A transdisciplinary didactic workshop was conducted aiming to promote a discussion about third included logic, an adequate logic to be applied to wave-particle duality. The data analysis allowed the following conclusions: (i) the students from the Physics teaching course at UFRPE had a previous concept about the wave-particle duality principle, but without a logic subjacent to this principle; (ii) the three experiments and the transdisciplinary workshop conducted during Kelly’s Experience Cycle contributed for a better comprehension about the wave-particle duality principle. / O objetivo deste trabalho foi investigar, numa turma de alunos da Licenciatura em Física da UFRPE, se o Pensamento Transdisciplinar pode contribuir para a compreensão do Princípio da Dualidade da Luz. A metodologia empregada foi o Ciclo da Experiência de Kelly, que teve a perspectiva de engajar os alunos em um processo de aprendizagem, com o auxílio de três experimentos didáticos: a cuba de onda, a dupla fenda de Young e o radiômetro de Crookes. A partir desses experimentos foi possível motivar uma discussão sobre as propriedades ondulatórias e corpusculares da luz. Uma oficina sobre a Transdisciplinaridade foi também realizada com o intuito de discutir a lógica do terceiro incluído, uma lógica que se adequa ao fato da luz se comportar como onda e como partícula. As análises dos dados permitiram as seguintes conclusões: (i) as concepções prévias dos estudantes da Licenciatura em Física da UFRPE acerca do Princípio da Dualidade da Luz eram desprovidas de uma lógica que respaldasse tal Princípio e (ii) os três experimentos propostos e a oficina sobre a Transdisciplinaridade, realizadas durante o Ciclo da Experiência Kellyana, contribuíram para que os estudantes tivessem uma maior compreensão do Princípio da Dualidade da Luz.

A new hypothesis of matter formation after the big bang based on either particle-wave duality or electric dipole asymmetry. Both assumptions allow to postulate that the probability of matter formation is slightly higher than that of antimatter formation. As a consequence, this difference of probabilities ∆Pp for protons and ∆Pe with regard to electrons avoided complete annihilation in the beginning.

Este trabalho relata a produção, implementação e avaliação de um curso sobre física quântica destinado a alunos do Ensino Médio. A unidade didática foi inspirada nas propostas de Ostermann et al. (2009) e Pessoa Jr. (1997, 2003). Ela introduz a física quântica considerando a óptica ondulatória como um contexto para introduzir algumas analogias conceituais básicas para conceitos fundamentais da física quântica. O conceito central desta abordagem é a dualidade onda-partícula e o Interferômetro Virtual de Mach-Zehnder (IVMZ) é utilizado como sua ferramenta didática principal ou, em termos vygotskyanos, ferramenta de mediação. A proposta foi aplicada no formato de uma oficina extracurricular em uma escola privada de Porto Alegre no Brasil. Um dos professores de Física da escola se engajou e colaborou com este projeto. As aulas ocorreram entre os meses de Outubro e Novembro de 2013, em encontros semanais de uma hora. A perspectiva sociocultural de Vygotsky foi utilizada para embasar as aulas do curso. A translinguística de Bakhtin e os conceitos vygotskyanos foram utilizados para a análise das falas dos estudantes durante as atividades do curso. Nesta perspectiva analítica buscamos compreender como os estudantes elaboram estratégias discursivas para entender o conceito de dualidade onda-partícula, analisando a importância das interações com parceiros mais capazes (como professores), textos, simulações e outras ferramentas didáticas. Os resultados indicam que os estudantes desenvolveram algum domínio das ferramentas mediacionais necessárias para compreender a dualidade onda-partícula em um nível satisfatório. O Interferômetro Virtual de Mach-Zehnder, os roteiros exploratórios e os professores mostraram-se importantes para tornar mais efetivas as experiências de aprendizagem dos estudantes. / This dissertation reports the development, implementation and evaluation of a quantum physics course directed to high school students. The course was conceived inspired in proposals of Ostermann et al. (2009) and Pessoa Jr. (1997, 2003). It introduces quantum physics considering wave optics as a context to introduce some basic conceptual analogies to quantum fundamental concepts. The core concept of this approach is the wave-particle duality and the Virtual Mach-Zehnder Interferometer (VMZI) is used as its main didactical tool or, in vygotskyan terms, a mediational tool. The course was applied as an extracurricular workshop in a private school from Porto Alegre, Brazil. One of the school´s Physics teacher collaborated and engaged in this project. The classes took place between October and November 2013, in a set of one-hour weekly meetings. Vygotsky´s sociocultural perspective is adopted to ground the practices of the course. Both Bakhtin´s translinguistics and Vygotsky’s concepts were used to perform the analysis of students’ utterances along didactical activities at the classes. In this analytical framework, we try to understand how students elaborate discursive strategies to understand the concept of wave-particle duality, analyzing the importance of interaction with more experienced peers (like teachers), texts, simulation and other teaching tools. The results indicate that the students developed some mastery of mediational means needed to understand the wave-particle duality at a satisfactory level. The Virtual Mach-Zehnder Interferometer, the exploratory guides and the teachers were important to enhance the students’ learning experiences.

Este trabalho relata a produção, implementação e avaliação de um curso sobre física quântica destinado a alunos do Ensino Médio. A unidade didática foi inspirada nas propostas de Ostermann et al. (2009) e Pessoa Jr. (1997, 2003). Ela introduz a física quântica considerando a óptica ondulatória como um contexto para introduzir algumas analogias conceituais básicas para conceitos fundamentais da física quântica. O conceito central desta abordagem é a dualidade onda-partícula e o Interferômetro Virtual de Mach-Zehnder (IVMZ) é utilizado como sua ferramenta didática principal ou, em termos vygotskyanos, ferramenta de mediação. A proposta foi aplicada no formato de uma oficina extracurricular em uma escola privada de Porto Alegre no Brasil. Um dos professores de Física da escola se engajou e colaborou com este projeto. As aulas ocorreram entre os meses de Outubro e Novembro de 2013, em encontros semanais de uma hora. A perspectiva sociocultural de Vygotsky foi utilizada para embasar as aulas do curso. A translinguística de Bakhtin e os conceitos vygotskyanos foram utilizados para a análise das falas dos estudantes durante as atividades do curso. Nesta perspectiva analítica buscamos compreender como os estudantes elaboram estratégias discursivas para entender o conceito de dualidade onda-partícula, analisando a importância das interações com parceiros mais capazes (como professores), textos, simulações e outras ferramentas didáticas. Os resultados indicam que os estudantes desenvolveram algum domínio das ferramentas mediacionais necessárias para compreender a dualidade onda-partícula em um nível satisfatório. O Interferômetro Virtual de Mach-Zehnder, os roteiros exploratórios e os professores mostraram-se importantes para tornar mais efetivas as experiências de aprendizagem dos estudantes. / This dissertation reports the development, implementation and evaluation of a quantum physics course directed to high school students. The course was conceived inspired in proposals of Ostermann et al. (2009) and Pessoa Jr. (1997, 2003). It introduces quantum physics considering wave optics as a context to introduce some basic conceptual analogies to quantum fundamental concepts. The core concept of this approach is the wave-particle duality and the Virtual Mach-Zehnder Interferometer (VMZI) is used as its main didactical tool or, in vygotskyan terms, a mediational tool. The course was applied as an extracurricular workshop in a private school from Porto Alegre, Brazil. One of the school´s Physics teacher collaborated and engaged in this project. The classes took place between October and November 2013, in a set of one-hour weekly meetings. Vygotsky´s sociocultural perspective is adopted to ground the practices of the course. Both Bakhtin´s translinguistics and Vygotsky’s concepts were used to perform the analysis of students’ utterances along didactical activities at the classes. In this analytical framework, we try to understand how students elaborate discursive strategies to understand the concept of wave-particle duality, analyzing the importance of interaction with more experienced peers (like teachers), texts, simulation and other teaching tools. The results indicate that the students developed some mastery of mediational means needed to understand the wave-particle duality at a satisfactory level. The Virtual Mach-Zehnder Interferometer, the exploratory guides and the teachers were important to enhance the students’ learning experiences.