### Abstract

We discuss BMS supertranslations both at null-infinity BMS^{−} and on the horizon B M S ^{ℋ} for the case of the Schwarzschild black hole. We show that both kinds of supertranslations lead to infinetly many gapless physical excitations. On this basis we construct a quotient algebra A≡ B M S ^{ℋ}/ B M S ^{−} using suited superpositions of both kinds of transformations which cannot be compensated by an ordinary BMS-supertranslation and therefore are intrinsically due to the presence of an event horizon. We show that transformations in A are physical and generate gapless excitations on the horizon that can account for the gravitational hair as well as for the black hole entropy. We identify the physics of these modes as associated with Bogolioubov-Goldstone modes due to quantum criticality. Classically the number of these gapless modes is infinite. However, we show that due to quantum criticality the actual amount of information-carriers becomes finite and consistent with Bekenstein entropy. Although we only consider the case of Schwarzschild geometry, the arguments are extendable to arbitrary space-times containing event horizons.

Original language | English (US) |
---|---|

Article number | 88 |

Journal | Journal of High Energy Physics |

Volume | 2016 |

Issue number | 6 |

DOIs | |

State | Published - Jun 1 2016 |

### Fingerprint

### Keywords

- Black Holes
- Classical Theories of Gravity
- Models of Quantum Gravity

### ASJC Scopus subject areas

- Nuclear and High Energy Physics

### Cite this

*Journal of High Energy Physics*,

*2016*(6), [88]. https://doi.org/10.1007/JHEP06(2016)088

**Gravitational black hole hair from event horizon supertranslations.** / Averin, Artem; Dvali, Gia; Gomez, Cesar; Lüst, Dieter.

Research output: Contribution to journal › Article

*Journal of High Energy Physics*, vol. 2016, no. 6, 88. https://doi.org/10.1007/JHEP06(2016)088

}

TY - JOUR

T1 - Gravitational black hole hair from event horizon supertranslations

AU - Averin, Artem

AU - Dvali, Gia

AU - Gomez, Cesar

AU - Lüst, Dieter

PY - 2016/6/1

Y1 - 2016/6/1

N2 - We discuss BMS supertranslations both at null-infinity BMS− and on the horizon B M S ℋ for the case of the Schwarzschild black hole. We show that both kinds of supertranslations lead to infinetly many gapless physical excitations. On this basis we construct a quotient algebra A≡ B M S ℋ/ B M S − using suited superpositions of both kinds of transformations which cannot be compensated by an ordinary BMS-supertranslation and therefore are intrinsically due to the presence of an event horizon. We show that transformations in A are physical and generate gapless excitations on the horizon that can account for the gravitational hair as well as for the black hole entropy. We identify the physics of these modes as associated with Bogolioubov-Goldstone modes due to quantum criticality. Classically the number of these gapless modes is infinite. However, we show that due to quantum criticality the actual amount of information-carriers becomes finite and consistent with Bekenstein entropy. Although we only consider the case of Schwarzschild geometry, the arguments are extendable to arbitrary space-times containing event horizons.

AB - We discuss BMS supertranslations both at null-infinity BMS− and on the horizon B M S ℋ for the case of the Schwarzschild black hole. We show that both kinds of supertranslations lead to infinetly many gapless physical excitations. On this basis we construct a quotient algebra A≡ B M S ℋ/ B M S − using suited superpositions of both kinds of transformations which cannot be compensated by an ordinary BMS-supertranslation and therefore are intrinsically due to the presence of an event horizon. We show that transformations in A are physical and generate gapless excitations on the horizon that can account for the gravitational hair as well as for the black hole entropy. We identify the physics of these modes as associated with Bogolioubov-Goldstone modes due to quantum criticality. Classically the number of these gapless modes is infinite. However, we show that due to quantum criticality the actual amount of information-carriers becomes finite and consistent with Bekenstein entropy. Although we only consider the case of Schwarzschild geometry, the arguments are extendable to arbitrary space-times containing event horizons.

KW - Black Holes

KW - Classical Theories of Gravity

KW - Models of Quantum Gravity

UR - http://www.scopus.com/inward/record.url?scp=84976277189&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84976277189&partnerID=8YFLogxK

U2 - 10.1007/JHEP06(2016)088

DO - 10.1007/JHEP06(2016)088

M3 - Article

AN - SCOPUS:84976277189

VL - 2016

JO - Journal of High Energy Physics

JF - Journal of High Energy Physics

SN - 1126-6708

IS - 6

M1 - 88

ER -