From: hitlong@yahoo.com   
      
   [Moderator's note: I forward this posting again since, according to the   
   sender it hasn't appeared in the Newsgroup, also it definitely appeared   
   via my news server.]   
      
   On Wednesday, June 2, 2021 at 12:47:01 PM UTC-6, Jos Bergervoet wrote:   
   >   
   > On 21/06/02 10:18 AM, stargene wrote:   
   >>   
   >> Profs. Susskind, =E2=80=99t Hooft and others have occasionally referred   
   >> to black hole event horizons as having tiny fluctuations in their   
   >> locations at the smallest micro-scales, due to QFT.   
   >>   
   >> For me, this implies that a graviton, say, just inside the horizon,   
   >> may find itself suddenly just outside of the horizon,   
   >   
   > You are wrong. Gravitons do not have a position, they are   
   > spread out. Most of the relevant ones are even very much spread   
   > out, in wavelenght modes as big as the entire blak hole.   
   >   
   > In QFT the term "particle" has nothing to do with classical   
   > point particles anymore, it has gotten a totally different   
   > meaning, referring to the numbering of different sections of   
   > the Hilbert space.   
   >   
   > In contrast, the concept of "event horizon" still has its   
   > classical meaning: infinitely thin shell with precise position   
   > coordinates! (Probably this will have to change as well if the   
   > theories are worked out further and then people will keep   
   > using the old word with a new meaning also in that case,   
   > adding further to the confusion..)   
   >   
   >> Two theorists confirmed that this could happen, but that more   
   >> work needed to be done on the union between QFT and the   
   >> BH horizon.   
   >   
   > Certainly! In particular we need to solve what happens if we   
   > describe a state as a superposition of states with different   
   > energy. The event horizon depends on this so it cannot be the   
   > classical concept based on exact position coordinates.   
   >   
   > The whole GR framework of classically describing the curvature   
   > of space-time based on the contained energy-momentum cannot   
   > work if there is a superposition of states with completely   
   > different energy-momentum values.   
   >> But doesn=E2=80=99t this imply that information from inside the horizon   
   >> can indeed propagate out into our universe,   
   > Well, if you first admit that there is "more work needed" then   
   > concluding things like that seems a bit premature..   
   >   
   >> ... at least in principle?   
   >> And if so, doesn=E2=80=99t QFT make it a whole new ball game regarding   
   >> connectivity between the two realms?   
   >   
   > The basic question may remain the same: does everything leak   
   > out into our universe again in the end (after BH evaporation) or   
   > will a remnant be split off indefinitely?   
   >   
   > --   
   > Jos   
      
   Isn't it so that from our perspective (far outside the event horizon) it   
   takes an infinite amount of time for an object falling into the BH to   
   reach the EH? Thus, perhaps, shouldn't we think about the probability   
   of a particle leaking INTO a BH in a finite time?   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)