TY - JOUR
T1 - Lectures on black holes and information loss
AU - Banks, T.
N1 - Funding Information:
*Lectures given at the Spring School on String Theory, Gauge Theory and Quantum Gravity, Trieste, April 1994. Supported in part by the Department of Energy under Grant No.DE-FG05-90ER40559.
Funding Information:
S.Giddings, and expecially A.Strominger were invaluable to me, and without them these lectures would be much less clear than they are. I would also like to take this opportunity to thank my collaborators, A.Dabolkhar, M.Douglas, and especially M.O'Loughlin for hours of enjoyable debate about the subject of black holes and information loss. My colleague S.Shenker deserves his usual acknowledgement for penetrating insights that have opened up whole new areas of investigation for me. The lectures were completed at the Aspen Center for Physics in the summer of 1994 and the Laboratoire de Physique Theorique of the Ecole Normale Superieure in Paris, in the fall. I would like to thank all of the members and staff of these institutions for their hospitality. I.Klebanov and R. Dijk-graaf also deserve a vote of thanks for organizing an excellent Spring School and twisting my arm to attend it. Finally, I would like to thank L.Susskind for many conversations about physics, and for continually challenging us all with his original insights. This work was supported in part by the Department of Energy under grant number DE-FG05-90ER40559.
PY - 1995/4
Y1 - 1995/4
N2 - In these lectures, the author's point of view on the problem of Hawking Evaporation of Black Holes is explained in some detail. A possible resolution of the information loss paradox is proposed, which is fully in accord with the rules of quantum mechanics. Black hole formation and evaporation leaves over a remnant which looks pointlike to an external observer with low resolving power, but actually contains a new infinite asymptotic region of space. Information can be lost to this new region without violating the rules of quantum mechanics. However, the thermodynamic nature of black holes can only be understood by studying the results of measurements that probe extremely small (sub-Planck scale) distances and times near the horizon. Susskind's description of these measurements in terms of string theory may provide an understanding of the Bekenstein-Hawking (BH) entropy in terms of the states of stranded strings that cross the horizon. The extreme nonlocality of string theory when viewed at short time scales allows one to evade all causality arguments which pretend to prove that the information encoded in the BH entropy can only be accessed by the external observer in times much longer than the black hole evaporation time. The present author believes however that the information lost in black hole evaporation is generically larger than the BH entropy, and that the remaining information is causally separated from the external world in the expanding horn of a black hole remnant or cornucopion. The possible observational signatures of such cornucopions are briefly discussed.
AB - In these lectures, the author's point of view on the problem of Hawking Evaporation of Black Holes is explained in some detail. A possible resolution of the information loss paradox is proposed, which is fully in accord with the rules of quantum mechanics. Black hole formation and evaporation leaves over a remnant which looks pointlike to an external observer with low resolving power, but actually contains a new infinite asymptotic region of space. Information can be lost to this new region without violating the rules of quantum mechanics. However, the thermodynamic nature of black holes can only be understood by studying the results of measurements that probe extremely small (sub-Planck scale) distances and times near the horizon. Susskind's description of these measurements in terms of string theory may provide an understanding of the Bekenstein-Hawking (BH) entropy in terms of the states of stranded strings that cross the horizon. The extreme nonlocality of string theory when viewed at short time scales allows one to evade all causality arguments which pretend to prove that the information encoded in the BH entropy can only be accessed by the external observer in times much longer than the black hole evaporation time. The present author believes however that the information lost in black hole evaporation is generically larger than the BH entropy, and that the remaining information is causally separated from the external world in the expanding horn of a black hole remnant or cornucopion. The possible observational signatures of such cornucopions are briefly discussed.
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U2 - 10.1016/0920-5632(95)00430-H
DO - 10.1016/0920-5632(95)00430-H
M3 - Article
AN - SCOPUS:4244108665
SN - 0920-5632
VL - 41
SP - 21
EP - 65
JO - Nuclear Physics B (Proceedings Supplements)
JF - Nuclear Physics B (Proceedings Supplements)
IS - 1-3
ER -