Can we observe fuzzballs or firewalls?

  • Bin Guo
  • Shaun HamptonEmail author
  • Samir D. Mathur
Open Access
Regular Article - Theoretical Physics


In the fuzzball paradigm the information paradox is resolved because the black hole is replaced by an object with no horizon. One may therefore ask if observations can distinguish a traditional hole from a fuzzball. We give arguments for why the fuzzball structure should lie close to the horizon; i.e., it should be a ‘tight’ fuzzball. We find: (a) It is very difficult to reflect quanta off the surface of such a fuzzball, mainly because geodesics starting near the horizon radius cannot escape to infinity unless their starting direction is very close to radial. (b) If infalling particles interact with the emerging radiation before they are engulfed by the horizon, then we say that we have a ‘firewall behavior’. We consider several types of interactions, but find no evidence for firewall behavior in any theory that obeys causality. (c) Photons with wavelengths larger than the black hole radius can be

scattered off the emerging radiation, but a very small fraction of the backscattered photons will be able to escape back to infinity.


Black Holes Black Holes in String Theory Models of Quantum Gravity 


Open Access

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Copyright information

© The Author(s) 2018

Authors and Affiliations

  1. 1.Department of PhysicsThe Ohio State UniversityColumbusU.S.A.

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