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Information Encoding in Quantum Gravity and the Black Hole Information Paradox

Project description

New research to illuminate the information encoding in quantum gravity

The discovery of gravitational waves emanating from merging black holes was a spectacular confirmation of Einstein’s general theory of relativity. However, physicists are still puzzled about the role of quantum mechanics as encapsulated by the black hole information paradox. When black holes radiate a small amount of heat (Hawking radiation), they lose mass in the process and ultimately evaporate. During evaporation, information must escape the black hole to avoid violating a central principle of quantum mechanics. The EU-funded HoloHair project aims to shed light on how black holes encode, store and emit information and whether information in quantum gravity in asymptotically flat spacetime is encoded via a holographic principle.


LIGO’s detection of merging black holes was a spectacular confirmation of general relativity (GR), yet it remains an open question whether black holes obey the same rules of quantum mechanics (QM) as all other known objects in the universe. Black holes are objects in GR which are known to have a vast entropy, but when QM is applied they evaporate by emission of Hawking radiation which carries no information about their microstates - this is the black hole information loss paradox which has evaded a resolution for over 40 years. The holographic AdS/CFT duality has provided indirect evidence that black holes are quantum mechanical systems that do not destroy information but the arguments are limited in scope to highly charged and/or spinning black holes and do not explain the gravitational dynamics near the horizon. To resolve the information paradox we need a better understanding of the information encoding, storage and flow between the horizon and the far asymptotic region where Hawking radiation escapes to, and more generally of how information is encoded in quantum gravity in asymptotically flat Minkowski spacetime. Achieving this is the overarching goal of this proposal. The novel research I propose combines two emergent ideas which could provide a paradigm changing picture of how black holes encode information: One is based on a thorough understanding of subtle long-distance effects in asymptotically flat spacetimes which give rise to “soft hair” and a horizon memory for black holes. The other is based on a mechanism in string theory, the most promising quantum completion of Einstein's theory of GR, which gives rise to horizon-scale microstructure, known as “fuzzballs”. The ground-breaking nature of this proposal is to bridge these two different approaches to develop a powerful new programme for solving the information paradox.



Net EU contribution
€ 829 963,81
Spui 21
1012WX Amsterdam

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West-Nederland Noord-Holland Groot-Amsterdam
Activity type
Higher or Secondary Education Establishments
Other funding
€ 0,00

Beneficiaries (2)