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Soft Hair on Black Holes

Posted January 09, 2016 8:07 PM by Bayes

Information Escaping Black Holes

In August 2015, Stephen Hawking made a presentation where he proposed a way information could escape destruction in a black hole. See links below:

https://www.youtube.com/watch?v=DkRDmJpthXg
Hawking Proposal

On January 5th, 2016, Hawking, Perry, and Strominger submitted a paper to arXiv.org that has expanded upon that initial idea and provided some details.

Here is the abstract to that paper:

It has recently been shown that BMS supertranslation symmetries imply an infinite number of conservation laws for all gravitational theories in asymptotically Minkowskian spacetimes. These laws require black holes to carry a large amount of soft (i.e. zeroenergy) supertranslation hair. The presence of a Maxwell field similarly implies soft electric hair. This paper gives an explicit description of soft hair in terms of soft gravitons or photons on the black hole horizon, and shows that complete information about their quantum state is stored on a holographic plate at the future boundary of the horizon. Charge conservation is used to give an infinite number of exact relations between the evaporation products of black holes which have different soft hair but are otherwise identical. It is further argued that soft hair which is spatially localized to much less than a Planck length cannot be excited in a physically realizable process, giving an effective number of soft degrees of freedom proportional to the horizon area in Planck units.

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#1

Re: Soft Hair on Black Holes

01/11/2016 12:03 AM
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Re: Soft Hair on Black Holes

01/11/2016 12:38 PM

But I though John Wheeler said black holes have no hair. Oh well, I can deal with soft hair.

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Re: Soft Hair on Black Holes

01/11/2016 4:35 PM

If you're close enough to see or feel the hair, you're much too close!

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