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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

Uma demonstração do teorema da singularidade de Hawking

Scarinci, Carlos Yoshio Uehara January 2009 (has links)
Apresentamos neste trabalho uma demonstração do teorema de singularidade de Hawking. Este é o mais simples de uma série de resultados em Relatividade Geral, os teoremas de Hawking-Penrose, que fornecem condições suficientes para a existência de singularidades geradas por colapsos gravitacionais. De fato, os teoremas nada falam da natureza destas singularidades, eles garantem apenas a incompletude geodésica, propriedade comumente aceita como o primeiro indício da existência de singularidades. No primeiro capítulo deste trabalho, começamos uma breve apresentação sobre variedades semi-riemannianas, dando atenção especial às variedades lorentzianas. No capítulo seguinte, obtemos alguns resultados do cálculo das variações que se mostrarão úteis para a demonstração do teorema. No último capítulo passamos ao estudo da teoria de causalidade em variedades lorentzianas e, finalmente, à prova do teorema de Hawking. / We present in this work a proof of Hawking's singularity theorem. This is the most simple of a series of results in General Relativity, the Hawking-Penrose theorems, which provides sufficient conditions for the existence af singularities generated by gravitational collapse. ln fact, the theorems say nothing about the nature of such singularities, they provide anly geodesic incampleteness, property commonly accepted as the first evidence af such singularities. ln the first chapter of this work, we began a brief presentatian on semi-riemannian manifolds, paying special attention to lorentzian manifolds. ln the following chapter, we obtain some results on calculus of variatians which turn out to be useful in the proof of the theorem. ln the last chapter we start studying causality theory lorentzian manifolds and, finally, the praaf of Hawking's theorem.
2

Uma demonstração do teorema da singularidade de Hawking

Scarinci, Carlos Yoshio Uehara January 2009 (has links)
Apresentamos neste trabalho uma demonstração do teorema de singularidade de Hawking. Este é o mais simples de uma série de resultados em Relatividade Geral, os teoremas de Hawking-Penrose, que fornecem condições suficientes para a existência de singularidades geradas por colapsos gravitacionais. De fato, os teoremas nada falam da natureza destas singularidades, eles garantem apenas a incompletude geodésica, propriedade comumente aceita como o primeiro indício da existência de singularidades. No primeiro capítulo deste trabalho, começamos uma breve apresentação sobre variedades semi-riemannianas, dando atenção especial às variedades lorentzianas. No capítulo seguinte, obtemos alguns resultados do cálculo das variações que se mostrarão úteis para a demonstração do teorema. No último capítulo passamos ao estudo da teoria de causalidade em variedades lorentzianas e, finalmente, à prova do teorema de Hawking. / We present in this work a proof of Hawking's singularity theorem. This is the most simple of a series of results in General Relativity, the Hawking-Penrose theorems, which provides sufficient conditions for the existence af singularities generated by gravitational collapse. ln fact, the theorems say nothing about the nature of such singularities, they provide anly geodesic incampleteness, property commonly accepted as the first evidence af such singularities. ln the first chapter of this work, we began a brief presentatian on semi-riemannian manifolds, paying special attention to lorentzian manifolds. ln the following chapter, we obtain some results on calculus of variatians which turn out to be useful in the proof of the theorem. ln the last chapter we start studying causality theory lorentzian manifolds and, finally, the praaf of Hawking's theorem.
3

Uma demonstração do teorema da singularidade de Hawking

Scarinci, Carlos Yoshio Uehara January 2009 (has links)
Apresentamos neste trabalho uma demonstração do teorema de singularidade de Hawking. Este é o mais simples de uma série de resultados em Relatividade Geral, os teoremas de Hawking-Penrose, que fornecem condições suficientes para a existência de singularidades geradas por colapsos gravitacionais. De fato, os teoremas nada falam da natureza destas singularidades, eles garantem apenas a incompletude geodésica, propriedade comumente aceita como o primeiro indício da existência de singularidades. No primeiro capítulo deste trabalho, começamos uma breve apresentação sobre variedades semi-riemannianas, dando atenção especial às variedades lorentzianas. No capítulo seguinte, obtemos alguns resultados do cálculo das variações que se mostrarão úteis para a demonstração do teorema. No último capítulo passamos ao estudo da teoria de causalidade em variedades lorentzianas e, finalmente, à prova do teorema de Hawking. / We present in this work a proof of Hawking's singularity theorem. This is the most simple of a series of results in General Relativity, the Hawking-Penrose theorems, which provides sufficient conditions for the existence af singularities generated by gravitational collapse. ln fact, the theorems say nothing about the nature of such singularities, they provide anly geodesic incampleteness, property commonly accepted as the first evidence af such singularities. ln the first chapter of this work, we began a brief presentatian on semi-riemannian manifolds, paying special attention to lorentzian manifolds. ln the following chapter, we obtain some results on calculus of variatians which turn out to be useful in the proof of the theorem. ln the last chapter we start studying causality theory lorentzian manifolds and, finally, the praaf of Hawking's theorem.
4

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
5

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.
6

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

Taylor, Quinn 23 May 2022 (has links)
No description available.
7

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.
8

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.
9

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.
10

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.

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