Quantum Fluctuation of Event Horizon of Black Hole
Project/Area Number  10640258 
Research Category 
GrantinAid for Scientific Research (C)

Allocation Type  Singleyear Grants 
Section  一般 
Research Field 
素粒子・核・宇宙線

Research Institution  KYOTO UNIVERSITY 
Principal Investigator 
SAKAGAMI Masaaki Fac.of Integrated Human studies, Kyoto University, Associated Prof., 総合人間学部, 助教授 (70202083)

Project Period (FY) 
1998 – 2000

Project Status 
Completed(Fiscal Year 2000)

Budget Amount *help 
¥2,600,000 (Direct Cost : ¥2,600,000)
Fiscal Year 2000 : ¥600,000 (Direct Cost : ¥600,000)
Fiscal Year 1999 : ¥700,000 (Direct Cost : ¥700,000)
Fiscal Year 1998 : ¥1,300,000 (Direct Cost : ¥1,300,000)

Keywords  black hole / Hawking radiation / higher derivative / horizon / fluctuation / fluid / 流体 / プランクスケール / モード変換 
Research Abstract 
A black hole means a spacetime region from which nobody can send a signal to observers at infinity. And this sort of the spacetime can be devided into two regions : one is exterior region which is causally connected to the infinity, another is interior region (black hole). We call a boundary of abobe two region "event horizon". However classical picture of black holes as "nothing can be emitted from the black hole" is drastically changed, if we take into account of quantum effects arround black holes. Prof.Hawking has been shown that black holes emit radiation originated by change of vacuum due to black hole formation. This so called Hawking radiation is recognized as the one of the most interesting phenomena of black hole. The Hawking radiation is a central issue of this research project. Radiations from black holes should climb up very deep potential in order to reach infinity. It follows that even if the radiation lies in a ordinary energy range of laboratories, its energy can exceed Planck scale near the horizon. This suggests the possibility that we access the physics beyond the Planck scale by means of Hawking radiation. In this research project, we investigated how the spectrum of the radiation modified, if we introduce a higher derivative term into scalar and electromagnetic fields which seems to mimic the effect of physics beyond the planck scale. Furthermore concentrating on the role of horizon, we propose an experiment in fluid to observe the phenomena which can be recognized as a acoustic analogue of the Hawking radiation. In this case, a sonic point where velocity of fluid exeeds sound velocity carries a role of horizon in the case of black hole. Finally, from a viewpoint of the fluctuationdisspation theorem, we discuss emergence of noise term which is caused by energyloss by Hawking radiation. This effect suggests the new perspective of black hole with a fluctuating horizon.

Report
(4results)
Research Output
(18results)