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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.
1

Tunneling model in Kruskal-Szekeres coordinates and information paradox

Yun, Zinkoo 06 February 2012 (has links)
In recent work by Kraus and Wilczek, it is first uncovered that small deviations from exact thermality in Hawking radiation have the capacity to carry off the maximum information content of a black hole. It is summarized, simplified and extended in this dissertation. This goes a considerable way toward resolving a long-standing “information loss paradox.” / Graduate
2

Quantum Corrections for (Anti)--Evaporating Black Hole

Maja Buri´c, Voja Radovanovi´c, rvoja@rudjer.ff.bg.ac.yu 25 July 2000 (has links)
No description available.
3

How the Universe Postpones the Evaporation and Curtails the Quantum Spreading of Black Holes

Taylor, Quinn 23 May 2022 (has links)
No description available.
4

Hawking Radiation and the Information Paradox

Gray, Sean January 2016 (has links)
This report presents a selfcontained derivation of Hawking radiation, and discusses the consequent information loss paradox.
5

A quantum Langevin approach to Hawking radiation

Abel, Paul Gordon January 2013 (has links)
An investigation of Hawking radiation and a method for calculating particle creation in Schwarzschild spacetime using a quantum Langevin approach is presented in this thesis. In particular we shall show that an oscillator confined to a free-fall trajectory in Schwarzschild spacetime radiates as a result of such motions, and this radiation can be interpreted as Hawking radiation. In chapter 1 we present a literature review of the underlying concept: the Unruh effect. We also present some introductory material pertinent to the calculations. Chapter 2 is concerned with the case of a thin collapsing shell to form a black hole in Schwarzschild anti-de Sitter spacetime. We determine the temperature of the black hole to be T[subscript H] = h(r[subscript h])/4π = κ/2π where h(r[subscript h]) is the factorization of the conformal factor, r is the radial coordinate with the location of the horizon situated atr = r[subscript h], and κ the surface gravity. We also calculate the stress tensor at early and late spacetimes which allows us to calculate the renormalized stress-tensor {T[subscript μν]} which satisfies the semi-classical Einstien field equations. In chapter 3 we examine the case of a harmonic oscillator in 2D Schwarzschild spacetime and we show that the choice of trajectory is responsible for making the oscillator radiate. In chapter 4 we derive a quantum Langevin equation for the oscillator in the Heisenberg picture. By solving this equation using the Wigner-Weiskopff approximation we show that, in the case of an oscillator confined to a free fall trajectory in Schwarzschild spacetime, the oscillator radiates with respect to the Boulware vacuum. In agreement with Hawking[1] we obtain a temperature of the black hole as T = 1/8πM[subscript B]. In chapter 5 we present our conclusions and recommendations for further work.
6

Higgs Formation At The Black Hole Decays At Large Hadron Collider

Sekmen, Sezen 01 January 2003 (has links) (PDF)
This thesis examines the possible creation of (4+n)-dimensional black holes at Large Hadron Collider (LHC) at CERN, consequent decays of such black holes via Hawking radiation and probable formation of Higgs boson among black hole decay products. Firstly, a theoretical background was presented including black hole physics, Hawking radiation, large extra dimensions, brane-bulk models, 4+n black holes and Higgs mechanism. Then, a simulation modeling black hole formation and decay including 130 GeV Higgs as a decay product at LHC interfaced with a detector simulation of Compact Muon Selenoid (CMS) was analysed focusing especially on the Higgs decay channels and properties of Hawking radiation. Both theoretical assumptions and simulation analysis point out that black hole production and the signatures of black hole decay products could carry crucial information on dimensionality and structure of spacetime Furthermore there is a significant possibility to observe 130 GeV Higgs boson especially in the Black Hole -&gt / H -&gt / jj and Black Hole -&gt / H &amp / #8211 / &gt / WW/ZZ -&gt / lnln decay channels.
7

Fuzzy blackholes

Murugan, Anand 01 May 2007 (has links)
The fuzzball model of a black hole is an attempt to resolve the many paradoxes and puzzles of black hole physics that have revealed themselves over the last century. These badly behaved solutions of general relativity have given physicists one of the few laboratories to test candidate quantum theories of gravity. Though little is known about exactly what lies beyond the event horizon, and what the ultimate fate of matter that falls in to a black hole is, we know a few intriguing and elegant semi-classical results that have kept physicists occupied. Among these are the known black hole entropy and the Hawking radiation process.
8

Radiação Hawking de um buraco negro acústico não-comutativo.

LUNA, Gabriela Coutinho. 06 November 2018 (has links)
Submitted by Emanuel Varela Cardoso (emanuel.varela@ufcg.edu.br) on 2018-11-06T20:40:37Z No. of bitstreams: 1 GABRIELA COUTINHO LUNA – DISSERTAÇÃO (PPGFísica) 2016.pdf: 715387 bytes, checksum: 874a57d0f89fb17ac576dd091e90bb48 (MD5) / Made available in DSpace on 2018-11-06T20:40:37Z (GMT). No. of bitstreams: 1 GABRIELA COUTINHO LUNA – DISSERTAÇÃO (PPGFísica) 2016.pdf: 715387 bytes, checksum: 874a57d0f89fb17ac576dd091e90bb48 (MD5) Previous issue date: 2016-02 / O estudo do buraco negro acústico, ou análogo acústico, se assemelha ao gravitacional da seguinte forma: verifi ca-se o fenômeno da radiação Hawking, apresença de um horizonte de eventos, a possibilidade de se calcular a sua temperatura, também chamada de temperatura Hawking, e obtêm-se uma métrica que descreve a geometria do buraco negro. Inserimos na métrica acústica a teoria não-comutativa, a fim de vericar as correções que resultam desta teoria. Neste trabalho, consideramos o princípio da incerteza generalizado, no formalismo de tunelamento via método de Hamilton-Jacobi, para determinar a temperatura Hawking e a entropia quântica corrigida para buracos negros acústicos não comutativo sem 2+1 dimensões. Em nossos resultados obtemos uma entropia de área, comum termo de correção logarítmica em ordem dominante um termo, em ordem menor, proporcional à temperatura de radiação associada com os buracos negros acústicos comutativos e um termo extra que depende de uma carga conservada. Assim, como no caso gravitacional, não há necessidade de apresentar o corte ultravioleta e as divergências são eliminadas. / Acoustic black hole study resembles the gravitational black hole as follows: we verify Hawking radiation phenomenon the presence of an event horizon, the possibility to calculate its temperature, also known as Hawking temperature, and we obtain a metric that describes the black hole geometry. We insert in the acoustic metric theory the non commutative theory in order to verify the corrections that result from this theory. In this study, we consider the generalized uncertainty principle in tunneling formalism by Hamilton-Jacobi method to determine Hawking temperature and quantum entropy corrected for non commutative acoustic black holes in 2+1 dimensions. In our results, we obtain an entropy are a with a termoflogarith mic correction in ruling order a termina smaller order, proportional to the radiation temperature associated with the commutative acoustic black holes and an extra term that depends on a conserved charge. Thus as in the gravitational case, there is noneed to present the ultraviolet cut-off and differences are eliminated.
9

On the phenomenology of quantum gravity : stability properties of Hawking radiation in the presence of ultraviolet violation of local Lorentz invariance / phénoménologie de la gravité quantique : Propriété de stabilité de la radiation d'Hawking en présence de violation de l'invariance local de Lorentz

Coutant, Antonin 01 October 2012 (has links)
Dans cette thèse, nous étudions plusieurs aspects de la radiation de Hawking en présence de violations de l'invariance locale de Lorentz. Ces violations sont introduites par une modification de la relation de dispersion, devenant non-linéaire aux courtes longueurs d’onde. Les principales motivations de ces travaux ont une double origine. Il y a d’une part le développement en matière condensée de trous noirs analogues, ou l’écoulement d’un fluide est perçu comme une métrique d’espace-temps pour les ondes de perturbations et ou la radiation de Hawking pourrait être détectée expérimentalement. D’autre part, il se pourrait que des effets de gravité quantique puissent être modélisés par une modification de la relation de dispersion. En premier lieu, nous avons obtenu des caractérisations précises des conditions nécessaires au maintien de l’effet Hawking en présence de violation de l’invariance de Lorentz. De plus, nous avons étudié l’apparition d’une onde macroscopique de fréquence nulle, dans des écoulements de type trous blancs et également pour des champs massifs. Une autre partie de ce travail a consisté à analyser une instabilité engendrée par les effets dispersifs, ou la radiation de Hawking est auto-amplifiée, générant ainsi un flux sortant exponentiellement croissant dans le temps. / In this thesis, we study several features of Hawking radiation in the presence of ultraviolet Lorentz violations. These violations are implemented by a modified dispersion relation that becomes nonlinear at short wavelengths. The motivations of this work arise on the one hand from the developing field of analog gravity, where we aim at measuring the Hawking effect in fluid flows that mimic black hole space-times, and on the other hand from the possibility that quantum gravity effects might be approximately modeled by a modified dispersion relation. We develop several studies on various aspects of the prob- lem. First we obtain precise characterizations about the deviations from the Hawking result of black hole radiation, which are induced by dispersion. Second, we study the emergence, both in white hole flows or for massive fields, of a macroscopic standing wave, spontaneously produced from the Hawking effect, and known as ‘undulation’. Third, we describe in detail an instability named black hole laser, which arises in the presence of two horizons, where Hawking radiation is self-amplified and induces an exponentially growing in time emitted flux.
10

Espinores exóticos e espinores RIM : aspectos físicos e algébricos /

Beghetto Junior, Dino January 2019 (has links)
Orientador: Julio Marny Hoff da Silva / Resumo: Espinores exóticos surgem quando a topologia da variedade $M$ tomada como sendo o espaço-tempo é suposta ser não-trivial, no sentindo que seu grupo fundamental é não-trivial: $\pi_1(M) \neq 0$. Assim, um novo termo exótico $\partial_\mu \theta$ surge na equação dinâmica destes espinores, e novas propriedades se apresentam. A não-trivialidade de $\pi_1(M)$ pode ser diretamente ligada a própria existência de buracos negros. Assim, estudamos, nesta tese, relações entre estruturas espinoriais exóticas e a taxa de emissão de radiação Hawking por buracos negros assintoticamente \textit{flat} em Relatividade Geral, encontrando equações diferenciais para o termo exótico, o que dá a possibilidade de inferir uma forma explícita para $\theta$. Também, tratamos aqui dos chamados espinores RIM, que são espinores que respeitam uma equação dinâmica não-linear chamada de equação não-linear de Heisenberg. Apresentamos dois lemas relativos a estes espinores: um deles encontrando restrições para ocorrer a decomposição de espinores de Dirac em termos de espinores RIM, e outro que nega a existência de espinores RIM exóticos, ou seja, relaciona a existência de espinores RIM a própria estrutura topológica do espaço-tempo. Ainda, encontramos um método de classificarmos os espinores RIM nas classes de Lounesto. Por fim, apresentamos, na forma de dois teoremas, maneiras de deformar homotopicamente tais espinores no que chamamos de \textit{spinor-plane}. / Abstract: Exotic spinors emerge when the topology associatd to the manifold $M$, which is token as being the spacetime, is suppose to be non-trivial, in the sense that its fundamental group is non-trivial: $\pi_1(M) \neq 0$. Thus, a new exotic term $\partial_\mu \theta$ rises from the dynamical equation related to these spinors, and new properties are in order. The non-triviality of $\pi_1(M)$ may be directly linked to the very existence of black holes. In this vein, we study some relations between exotic spinorial structures and the Hawking radiation emission rate by asymptotically flat black holes solutions of General Relativity, finding an equation from which an explicity form for the exotic term could be inferred. Moreover, we work on the so-called RIM spinors, which are spinor fields satisfying a non-linear dynamical equation known as Heiseing non-linear equation. We present two \textit{lemmata} related to these spinors: one of them gives us restrictions for the decompostion of Dirac fields in terms of RIM spinors to occur, while the other deny the existence of exotic RIM spinors, i.e., it relates the very existence of RIM spinors to the spacetime topological structure. Besides, we develop a classifying method for RIM spinors into the Lounesto classes. Finally, we present, in the form of two theorems, ways to homotopically deform such spinors in what we call the spinor-plane. / Doutor

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