On Sunday, January 14, 2018 at 5:54:50 PM UTC-6, John Clark wrote: > > Hi Lawrence, thanks for a very interesting post. > > > >> The vacuum is filled with virtual pairs of fields. With a black hole the >> gravity field causes one of these pairs to fall into the black hole and the >> other to escape. This means the quantum particle or photon that escapes as >> Hawking radiation is entangled with the pair that falls into the black >> hole, and so this means Hawking radiation is entangled with the black hole. >> So at first blush there seems to be no problem. However, if we think of a >> thermal cavity heated to high temperature photons that escape are entangled >> with quantum states of atoms composing the cavity. Once the entanglement >> entropy reaches a maximum at half the energy released the subsequent >> photons released are entangled with prior photons released. This would hold >> with black holes as well, but because of the virtual pair nature of this >> radiation it means Hawking radiation previously emitted in a bipartite >> entanglement are now entangled not just with the black hole, but with more >> recently emitted radiation as well. This means a bipartite entanglement is >> transformed into a tripartite entanglement. Such transformations are not >> permitted by quantum unitary evolution. This is called quantum monogamy >> requirement, and what this suggests is unitarity fails. To prevent the >> failure of quantum mechanics some proposed a firewall that violates the >> equivalency principle. This is called a firewall. >> > The firewall occurs when half the possible radiation is emitted, which is >> also the Page time. >> > > You clearly explain why after half the Black Hole has evaporated further > radiated photons would, on the face of it, be entangled with 3 things, and > if that is forbidden by quantum mechanics then one of those entanglements > would need to be broken > . > > But > what I don't understand is why breaking the > quantum > link with the Black Hole would make things hot. > > Joseph Polchinski, they guy who came up with the firewall idea said: > > > > *“It’s a violent process, like breaking the bonds of a molecule, and it > releases energy.The energy generated by severing lots of twins would be > enormous. The event horizon would literally be a ring of fire that burns > anyone falling through”* > But why? Why would breaking quantum entanglement release energy and > produce heat, what does one have to do with the other? > > > >> > >> This also corresponds to the failure of a quantum error correction code. >> > > > Please correct me if I'm wrong but I think you're saying before half the > Black Hole has evaporated you could hypothesize than although it looks > random maybe information i > s > encoded in the Hawking radiation in some very elaborate way, but after > that it would be impossible even in theory. A connection between Black > Holes and quantum error correcting codes is really intriguing! > I take it > you think the information about the stuff that formed the Black Hole is > truly lost > . > Or is there some way out? > > > > John K Clark >
The firewall is a bit of a phenomenological "patch." If the equivalence principle is violated so as to prevent any passage of quanta in or out of the black hole then in some ways the singularity of the black hole appears where the horizon should be. The singularity would in some ways be similar to the singularity that occurs for an extremal black hole, where it communicates no information to the outside world. The idea is in some ways a bit odd, and it really is meant to illustrate an obstruction to our understanding on how quantum mechanics works with gravitation. LC -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
