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Hawking Radiation from Some Particular Black Holes

Thesis Info

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External Link

Author

Javed, Wajiha

Program

PhD

Institute

University of the Punjab

City

Lahore

Province

Punjab

Country

Pakistan

Thesis Completing Year

2013

Thesis Completion Status

Completed

Subject

Mathemaics

Language

English

Link

http://prr.hec.gov.pk/jspui/bitstream/123456789/2315/1/2532S.pdf

Added

2021-02-17 19:49:13

Modified

2024-03-24 20:25:49

ARI ID

1676726358869

Similar


We first investigate quantum corrections to the thermodynamical quantities (temperature and entropy) for a charged Bardeen and Ay ́n-Beato-Garc ́ o ıa- Bronnikov regular black holes by using a quantum tunneling approach be- yond the semiclassical approximation. It is found that the leading order correction to the entropy is of logarithmic form. We also examine the effects of space noncommutativity on the thermodynamics of a Bardeen charged regular black hole. For a suitable choice of sets of parameters, the behavior of the singularity, horizon, mass function, black hole mass, temperature, entropy and its differential, area and energy distribution of the Bardeen solution is discussed graphically for both noncommutative and commuta- tive spaces. It turns out that the commutative coordinates extrapolate all such quantities (except temperature) for a given set of parameters. It is interesting to mention here that these sets of parameters provide that there is no singularity (essential for r = 0) for the black hole solution both in noncommutative and commutative spaces. We also study the black hole evaporation and Hawking radiation for a noncommutative charged Vaidya black hole. For this purpose, we determine spherically symmetric charged Vaidya model and then formulate a noncom- mutative Reissner-Nordstr ̈m-like solution of this model which leads to an o exact (t − r) dependent metric. The behavior of temporal component of this metric and the corresponding Hawking temperature is investigated. Further, we examine the tunneling process of the charged massive particles through the quantum horizon. It is found that the tunneling amplitude is modified due to noncommutativity. Also, it turns out that black hole evaporates completely in the limits of large time and horizon radius. It is mentioned here that the final stage of black hole evaporation leads to a naked singularity. Finally, we explore Hawking radiation as a tunneling process of charged fermions through event horizons of the charged regular black holes, i.e., Bardeen and ABGB black holes as well as of a pair of charged accelerating and rotating black holes with NUT parameter. We apply the semiclassical WKB approximation to the general covariant Dirac equation of charged par- ticles and evaluate the tunneling probabilities of outgoing charged particles. The Hawking temperature corresponding to these black holes are recovered. We also consider the back-reaction effects of the emitted spin particles from black holes and calculate their corresponding quantum corrections to the radiation spectrum. It is found that this radiation spectrum is not purely thermal due to energy and charge conservation but has some corrections. In the absence of charge and NUT parameter, we find consistent results with those already present in the literature.
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حدود کےنفاذ کی شرائط

حدود کےنفاذ کی شرائط
حدود کی تنفیذ کے لیے مندرجہ ذیل شرائط کا پورا ہونا ضروری ہے:
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"استيفاء الحد إلى الإمام"38 "حد کا استیفا ء امام کا کام ہے۔ "
حاکم وقت یا اس کا نمائندہ ہی حد کا نفاذ کر سکتا ہے ، جیسا کہ علامہ مرغینانی ؒ تحریر کرتے ہیں کہ
"حد قائم کرنے کے لیے ضروری ہے اس کو امیرالمومنین یا حاکم وقت یا حاکم کا نمائندہ قائم کرے۔ "39
2۔ آزاد ، عاقل ، بالغ اور مرضی سے فعل سر انجام دینے والے پر حد جاری ہوتی ہے۔ علامہ مرغینانی لکھتے ہیں جس پر حد لگائی جائے وہ "آزاد ، عاقل ، بالغ ہواور یہ فعل آزاد ی و مرضی سے ہوا ہو۔ "40
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