Deeg, Dorothea (2006): Quantum Aspects of Black Holes. Dissertation, LMU München: Faculty of Physics 

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Abstract
In this thesis we study two quantum aspects of black holes, their entropy and the Hawking effect. First, we present a model for the statistical interpretation of black hole entropy and show that this entropy emerges as a result of missing information about the exact state of the matter from which the black hole was formed. We demonstrate that this idea can be applied to black holes made from both ultrarelativistic and nonrelativistic particles. In the second part we focus our attention on several features of black hole evaporation. We discuss the dependence of the Hawking radiation on the vacuum definition of different observers. It becomes evident that in certain cases the choice of observer has an influence on the particle spectrum. In particular, we study the meaning of the Kruskal vacuum on the horizon. After that we determine the Hawking flux for nonstationary black holes. We find approximate coordinates which are regular on the time dependent horizon and calculate the particle density measured by an observer at infinity. Finally, we derive the response of a particle detector in curved background. In our approach we use the Unruh detector to quantify the spectrum of radiation seen by general observers in Minkowski, Schwarzschild and Vaidya spacetimes. We find that an arbitrarily accelerated detector in flat spacetime registers a particle flux with a temperature proportional to a time dependent acceleration parameter. A detector moving in Schwarzschild spacetime will register a predominantly thermal spectrum with the exact temperature depending on the observer's trajectory. If the detector is located at constant distance from the black hole it measures a shifted temperature which diverges on the horizon. On the other hand, a detector in free fall towards the black hole does not register a thermal particle flux when it crosses the horizon. In this framework corrections to the temperature measured by a detector moving in Vaidya spacetime are obtained as well. We argue that our result also clarifies the role of horizons in black hole radiation.
Item Type:  Thesis (Dissertation, LMU Munich) 

Keywords:  black holes, Hawking effect, entropy, detector 
Subjects:  600 Natural sciences and mathematics > 530 Physics 600 Natural sciences and mathematics 
Faculties:  Faculty of Physics 
Language:  English 
Date Accepted:  26. July 2006 
1. Referee:  Mukhanov, Viatcheslav 
Persistent Identifier (URN):  urn:nbn:de:bvb:1960243 
MD5 Checksum of the PDFfile:  ff4a531e9d430199b494c682d8ab7df4 
Signature of the printed copy:  0001/UMC 15835 
ID Code:  6024 
Deposited On:  13. Dec 2006 
Last Modified:  16. Oct 2012 08:02 