Thesis (Ph. D.)--University of Wisconsin--Madison, 1973. / Typescript. Vita. Includes bibliographical references.

Techn. University, Diss., 2001--Dresden.

F'ritz: von Unruh, who lives at Oranieuhof in Diez an der Lahn, was born in 1885. He wrote the first two parts of his trilogy Ein Geschlecht during the literary movement in Germany which is known as Expressionismus". The yet, unpublished third part was not finished until 1958. It was in this trilogy that he developed his ideas of a new world. The upheaval and destruction of World War I shattered the complacency of life and traditions which had so long been ingrained in Europe. This traumatic experience resulted in a new examination of life, its meaning and sense. The stark reality in which Germany found herself after the war and the contradictory abundance of material, intellectual and spiritual striving in social and economic worlds appeared as a prelude for a new order in the world Gestalt. It was during this time that Unruh began work on his trilogy which was to incorporate his idea of a new world. Two facts are especially important in the development of his ideas. First, he himself was of noble birth. The traditions of unquestionable service and loyalty to church and state were a part of him. The sense of duty which was deeply ingrained in him experienced, however, a fundamental change. This change became the nucleus for his trilogy. Secondly, his experiences as an officer in World War I served as an impetus in the development of his Weltanschauung. His newly found idea of a new world may be seen as an evolving process which first finds expression in his war poem Vor der Entscheidung and is brought to realization in the trilogy. 'The central theme of this thesis is an interpretation of these works which will show the development of his ideas. They lead us from rebellion to chaos and to a new cosmos.

This thesis considers entanglement, an important resource for quantum information processing tasks, while taking into account the theory of relativity. Not only is this a more complete description of quantum information, but it is necessary to fully understand quantum information processing tasks done by systems in arbitrary motion. It is shown that accelerated measurements on the vacuum of a free Dirac spinor field results in an entangled state for an inertial observer. The physical mechanism at work is the Davies-Unruh effect. The entanglement produced increases as a function of the acceleration, reaching maximal entanglement in the asymptotic limit of infinite acceleration. The dynamics of entanglement between two Unruh-DeWitt detectors, one stationary and the other undergoing non-uniform acceleration, was studied numerically. In the ultraweak coupling limit, the entanglement decreases as a function of time for the parameters considered and decreases faster than if the moving detector had had a uniform acceleration.

This thesis considers entanglement, an important resource for quantum information processing tasks, while taking into account the theory of relativity. Not only is this a more complete description of quantum information, but it is necessary to fully understand quantum information processing tasks done by systems in arbitrary motion. It is shown that accelerated measurements on the vacuum of a free Dirac spinor field results in an entangled state for an inertial observer. The physical mechanism at work is the Davies-Unruh effect. The entanglement produced increases as a function of the acceleration, reaching maximal entanglement in the asymptotic limit of infinite acceleration. The dynamics of entanglement between two Unruh-DeWitt detectors, one stationary and the other undergoing non-uniform acceleration, was studied numerically. In the ultraweak coupling limit, the entanglement decreases as a function of time for the parameters considered and decreases faster than if the moving detector had had a uniform acceleration.

The purpose of this investigation is to arrive at an understanding of Fritz von Unruh's work by examining the author's modes of characterization. Unruh repeatedly introduces kindred characters, character types, and configurations of characters, but uses differing methods of characterization to portray them. By investigating the works completed between 1910 and 1932 and by relating Unruh's techniques of characterization to the total structure of these works, a pattern may be observed which demonstrates that Unruh gradually adapts pre-Expressionist methods of characterization to those typically associated with Expressionism, by depersonalizing hi; characters and by subordinating them to the portrayal of one central figure. This pattern has its roots in the pre-war dramas, culminates in the works completed during the war, and attenuates in the post-war plays. The various stages of this metamorphosis are ultimately related to the message-oriented nature of the works. In the early plays, the conventions of pre-Expressionist drama are gradually adapted to suit the portrayal of contemporary Wilhelminian reality and of a central figure who fights for a reintroduction of the ideals of the past. In the works completed between 1914 and 1918 the author subjects his major characters to a transformation: he presents the figures as types, uses a form of character fragmentation, and makes the plot development as well as the scenic and dialogue composition subservient to the propagation of the ideas incorporated by the central characters. In the post-war plays, finally, each of these modes of character delineation is increasingly less subservient to the major figures, but characterizes the negative, unredeemed world about them, against which they have to assert themselves. In these plays, the redemption of man is no longer sought in a past or present reality, but in a realm in which objective reality is transfigured and transformed. / Arts, Faculty of / Central Eastern Northern European Studies, Department of / Graduate

No description available.

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.

Submitted by Emanuel Varela Cardoso (emanuel.varela@ufcg.edu.br) on 2018-10-18T18:35:27Z No. of bitstreams: 1 LUIZ CORDEIRO DE LIMA NETO – DISSERTAÇÃO (PPGFísica) 2013.pdf: 963611 bytes, checksum: 83952da12a3c82dcd16e85616b111271 (MD5) / Made available in DSpace on 2018-10-18T18:35:27Z (GMT). No. of bitstreams: 1 LUIZ CORDEIRO DE LIMA NETO – DISSERTAÇÃO (PPGFísica) 2013.pdf: 963611 bytes, checksum: 83952da12a3c82dcd16e85616b111271 (MD5) Previous issue date: 2013-03-26 / Capes / Este trabalho apresenta elementos complementares da formação no nível de mestrado em Física. Discutimos, principalmente, aspectos de Relatividade Geral e Teoria Quân- tica de Campos. Deforma detalhada, explanamos a obtenção das soluções de Reissner- Nordström para as equações de Einstein que mostram a dependência dos buracos negros carregados da sua massa e da sua carga. Analisamos, também, os casos onde a massa difere numericamente da carga conhecidos como casos não-extremos, e os casos onde estas grandezas são equivalentes conhecidos como extremos. Discutimos, também, as leis da mecânica dos buracos negros e a inevitável comparação com as leis usuais da Termodinâmica e, conforme foi demonstrado por Hawking, que essas semelhanças são um fenômeno físico explicado pela a mecânica quântica. Ao rever estes estudos, Unruh percebeu que um observador acelerado em um espaço plano mede radiação térmica. Os estudos apresentados nesta dissertação constituem o embasamento necessário para o trabalho em inúmeras áreas de desenvolvimento da Física na atualidade, visto que os buracos negros carregados (em dimensões extras) possuem uma ligação com a teoria das cordas, uma das teorias mais promissoras para a construção da teoria quântica da gravitação. / This work presents complementary elements of training at the master’s degree level in Physics. We discussed, mainly, aspects of General Relativity and Quantum Field Theory. In details we expounded the obtaining of Reissner-Nordström’s solutions for Einstein’s equations that show the dependence of charged black holes on their massand charge. We also the cases in which the mass differs numerically from charge, known as non- extreme cases, and cases where the sequantities are equivalent, known as extreme. We also discuss the laws of mechanics of black holes and thein evitable comparison with the usual law softhermo dynamics and still, as demonstrated by Hawking, that the se similarities are physical phenomena explained by Quantum Mechanics. By reviewing thes estudies, Unruh realized that an accelerated observerina flat space me asures thermal radiation. The studies presented in this dissertation formed the necessary principles for research in several are as of development of physics now a days, where as the charged black holes (in extradimensions) are connected with the String Theory, one of the most promising theories for construction of the Quantum Theory of Gravitation.

The setup in which two quantum systems, Alice and Bob, communicate using bosonic field quanta can be viewed as a prototype for wireless quantum communication. In this thesis we focus on the most basic case, where Alice and Bob are modeled as Unruh-DeWitt detectors, i.e., as two-level quantum systems that interact locally through a scalar quantum field. Our aim is to study how information propagation and entanglement generation between the two detectors are impacted by both relativity and by the unavoidable noise that is due to the quantum fluctuations of the field. We start by studying information propagation between the two detectors. Concretely, we construct and study the information-theoretic quantum channel, ξ, i.e., the completely positive trace preserving map between the input density matrix ϱ, in which Alice prepares her detector for the emission, and the output density matrix ϱ '=ξ(ϱ) of Bob's detector at a later time. We confirm that the classical as well as the quantum channel capacity are strictly zero to all orders in perturbation theory for spacelike separations. We then study entanglement generation between the two detectors. Specifically, we discuss how two Unruh-DeWitt detectors can extract entanglement from the vacuum. We show that the detectors can naturally and instantaneously become entangled through a Casimir-Polder effect. We then analyze the impact of various additions to this setup, such as the presence of a weak gravitational field, the presence of boundary conditions in the field, the presence of a weak classical potential, etc.