Diving into traversable wormholes (1704.05333v1)

Abstract: We study various aspects of wormholes that are made traversable by an interaction beween the two asymptotic boundaries. We concentrate on the case of nearly-$AdS_2$ gravity and discuss a very simple mechanical picture for the gravitational dynamics. We derive a formula for the two sided correlators that includes the effect of gravitational backreaction, which limits the amount of information we can send through the wormhole. We emphasize that the process can be viewed as a teleportation protocol where the teleportee feels nothing special as he/she goes through the wormhole. We discuss some applications to the cloning paradox for old black holes. We point out that the same formula we derived for $AdS_2$ gravity is also valid for the simple SYK quantum mechanical theory, around the thermofield double state. We present a heuristic picture for this phenomenon in terms of an operator growth model. Finally, we show that a similar effect is present in a completely classical chaotic system with a large number of degrees of freedom.

• The paper introduces a mechanism enabling traversability by coupling two asymptotic boundaries in nearly-AdS2, allowing controlled information transfer.
• It employs a mechanical model with two-sided correlators to quantify gravitational backreaction, dictating the limits on information capacity.
• The study leverages the SYK model and classical chaos frameworks to address black hole information paradoxes and underline quantum gravity dualities.

Overview of the Study on Traversable Wormholes

The paper under consideration explores the intriguing concept of traversable wormholes within the framework of nearly-AdS$_2$ gravity. The research proposes a mechanism by which wormholes, traditionally non-traversable within classical general relativity, can become traversable through an interaction between the two asymptotic boundaries of the wormhole. This is a theoretical investigation that explores the gravitational dynamics, introducing novel insights into the duality of AdS space and quantum mechanical systems.

Fundamentally, the authors examine a simple mechanical model for the gravitational dynamics in nearly-AdS$_2$ space, deriving a formula for two-sided correlators. This formula incorporates the effects of gravitational backreaction, highlighting a limiting factor on the volume of information transferable through the wormhole. The process is intriguingly framed as a teleportation protocol—remarkably, the entity being teleported experiences no discernable effects during transit through the wormhole.

Key Results and Claims

• Traversability and Information Transfer: The authors present a method, derived from modifying the dual quantum system, that allows a signal to be sent through a wormhole. This is achieved via a simple coupling mechanism between the states at the boundary, thus rendering the wormhole navigable. The paper claims that the gravitational backreaction restricts the quantity of information that traverses the wormhole, ensuring that the information exchanged is somewhat proportional to the interaction strength.
• Applications to Paradoxes in Black Hole Physics: The paper addresses implications for the black hole information paradox, particularly the cloning paradox related to quantum states. The traversable nature of the wormholes provides a unique physical realization of information recovery processes such as the Hayden-Preskill protocol in quantum systems.
• Modeling via SYK Theory and Classical Chaotic Systems: To further ground the theoretical insights, the authors employ both the Sachdev-Ye-Kitaev (SYK) model and classical chaotic frameworks, illustrating traversability in diverse systems. Notably, the SYK model provides a concrete quantum mechanical setting where the same correlators, as derived for AdS$_2$ gravity, effectively describe the dynamics, underscoring the relevance of these findings across different theoretical landscapes.

Implications and Prospective Developments

The implications of this paper are both theoretical and practical. Practically, understanding traversable wormholes could have significant repercussions in the context of quantum information science, specifically in quantum teleportation and information recovery in the presence of horizons such as those of black holes.

Theoretically, this work contributes to the ongoing dialogue concerning the AdS/CFT correspondence and quantum gravity. In particular, the simplification of AdS$_2$ gravitational dynamics presented here suggests future research directions, such as deeper explorations into the dualities of low-dimensional quantum gravity and extensions to higher dimensions and more complex boundary conditions.

The application to classical chaotic systems marks an intriguing attempt to bridge classical mechanics with quantum gravitational phenomena, potentially offering new insights into the chaotic dynamics governing both realms.

As research progresses, these findings could stimulate new theoretical models and experimental setups aimed at exploring fundamental questions about the nature of spacetime and the transfer of information across quantum systems and black holes. Further understanding of these mechanisms might one day assist in unraveling the numerous remaining mysteries of quantum gravity.