Violation of unitarity by Hawking radiation does not violate energymomentum conservation
Abstract
An argument by Banks, Susskind and Peskin (BSP), according to which violation of unitarity would violate either locality or energymomentum conservation, is widely believed to be a strong argument against nonunitarity of Hawking radiation. We find that the whole BSP argument rests on the crucial assumption that the Hamiltonian is not highly degenerate, and point out that this assumption is not satisfied for systems with many degrees of freedom. Using Lindblad equation, we show that high degeneracy of the Hamiltonian allows local nonunitary evolution without violating energymomentum conservation. Moreover, since energymomentum is the source of gravity, we argue that energymomentum is necessarily conserved for a large class of nonunitary systems with gravity. Finally, we explicitly calculate the Lindblad operators for nonunitary Hawking radiation and show that they conserve energymomentum.
 Authors:
 Theoretical Physics Division, Rudjer Bošković Institute, P.O.B. 180, HR10002 Zagreb (Croatia)
 Publication Date:
 Sponsoring Org.:
 SCOAP3, CERN, Geneva (Switzerland)
 OSTI Identifier:
 22454535
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2015; Journal Issue: 04; Other Information: PUBLISHERID: JCAP04(2015)002; OAI: oai:repo.scoap3.org:9836; Article funded by SCOAP3. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 License. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BLACK HOLES; DEGREES OF FREEDOM; GALACTIC EVOLUTION; GRAVITATION; HAMILTONIANS; INVARIANCE PRINCIPLES; QUANTUM FIELD THEORY; UNITARITY
Citation Formats
Nikolić, Hrvoje. Violation of unitarity by Hawking radiation does not violate energymomentum conservation. United States: N. p., 2015.
Web. doi:10.1088/14757516/2015/04/002.
Nikolić, Hrvoje. Violation of unitarity by Hawking radiation does not violate energymomentum conservation. United States. doi:10.1088/14757516/2015/04/002.
Nikolić, Hrvoje. 2015.
"Violation of unitarity by Hawking radiation does not violate energymomentum conservation". United States.
doi:10.1088/14757516/2015/04/002.
@article{osti_22454535,
title = {Violation of unitarity by Hawking radiation does not violate energymomentum conservation},
author = {Nikolić, Hrvoje},
abstractNote = {An argument by Banks, Susskind and Peskin (BSP), according to which violation of unitarity would violate either locality or energymomentum conservation, is widely believed to be a strong argument against nonunitarity of Hawking radiation. We find that the whole BSP argument rests on the crucial assumption that the Hamiltonian is not highly degenerate, and point out that this assumption is not satisfied for systems with many degrees of freedom. Using Lindblad equation, we show that high degeneracy of the Hamiltonian allows local nonunitary evolution without violating energymomentum conservation. Moreover, since energymomentum is the source of gravity, we argue that energymomentum is necessarily conserved for a large class of nonunitary systems with gravity. Finally, we explicitly calculate the Lindblad operators for nonunitary Hawking radiation and show that they conserve energymomentum.},
doi = {10.1088/14757516/2015/04/002},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 04,
volume = 2015,
place = {United States},
year = 2015,
month = 4
}

An argument by Banks, Susskind and Peskin (BSP), according to which violation of unitarity would violate either locality or energymomentum conservation, is widely believed to be a strong argument against nonunitarity of Hawking radiation. We find that the whole BSP argument rests on the crucial assumption that the Hamiltonian is not highly degenerate, and point out that this assumption is not satisfied for systems with many degrees of freedom. Using Lindblad equation, we show that high degeneracy of the Hamiltonian allows local nonunitary evolution without violating energymomentum conservation. Moreover, since energymomentum is the source of gravity, we argue that energymomentummore »

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