The Transfer of Entanglement: The Case for Firewalls

TL;DR

This paper discusses how entanglement transfer in black holes relates to the firewall paradox, suggesting that the completion of entanglement transfer at the Page time leads to the formation of a firewall, with implications for black hole complementarity.

Contribution

It introduces the principle of 'transfer of entanglement' for one-sided black holes and connects it to the firewall hypothesis, providing a new perspective on black hole interior reconstruction.

Findings

Entanglement transfer completes at the Page time.

Firewall formation coincides with entanglement transfer completion.

Alternatives to firewalls face similar contradictions as time travel.

Abstract

Black hole complementarity requires that the interior of a black hole be represented by the same degrees of freedom that describe its exterior. Entanglement plays a crucial role in the reconstruction of the interior degrees of freedom. This connection is manifest in "two-sided" eternal black holes. But for real black holes which are formed from collapse there are no second sides. The sense in which horizon entropy is entanglement entropy is much more subtle for one-sided black holes. It involves entanglement between different parts of the near-horizon system. As a one-sided black hole evaporates the entanglement that accounts for its interior degrees of freedom disappears, and is gradually replaced by entanglement with the outgoing Hawking radiation. A principle of "transfer of entanglement" can be formulated. According to the argument of Almheiri, Marolf, Polchinski and Sully, it is when the transfer of entanglement is completed at the Page time, that a firewall replaces the horizon. Alternatives to firewalls may suffer contradictions which are similar to those of time travel. The firewall hypothesis would be similar to Hawking's chronology protection conjecture.