Creating a traversable wormhole

Abstract

We argue that one can nucleate a traversable wormhole via a nonperturbative process in quantum gravity. To support this, we construct spacetimes in which there are instantons giving a finite probability for a test cosmic string to break and produce two particles on its ends. One should be able to replace the particles with small black holes with only small changes to the spacetime away from the horizons. The black holes are then created with their horizons identified, so this is an example of nucleating a wormhole. Unlike previous examples where the created black holes accelerate apart, in our case they remain essentially at rest. This is important since wormholes become harder and harder to make traversable as their mouths become widely separated, and since traversability can be destroyed by Unruh radiation. In our case, back-reaction from quantum fields can make the wormhole traversable.

Traversable wormholes in AdS and bounds on information transfer

“…In the context of AdS/CFT, the fact that entanglement is not enough to build a traversable wormhole in AdS, but one needs an explicit coupling between the left and right asymptotic regions was already noted in [20,21]. After GJW, traversable wormholes were further explored for the case of AdS 2 in [5], while recent attempts to construct eternal wormholes include [8,12,[22][23][24]. The case of rotating wormholes in AdS was studied in [4].…”

Ellis wormhole without a phantom scalar field

“…In all cases it was found that given two points, one on each side of the wormhole's throat, it will take longer to go from one point to the other through the wormhole, instead of around it. More recently [12] it was shown that wormholes can also be produced through a quantum tunneling event, where a backreaction from quantum fields can make these wormholes traversable.…”

Lectures on faster-than-light travel and time travel

“…This surface is a narrow strip (of width 2) winding around the t axis. Two linearly independent tangent vectors to this 2-dimensional surface are ∂ r (which points across the short side of the strip) and ∂ t + 2∂ φ (which points up the long side of the strip), and they are both spacelike 33 . Thus, the surface is spacelike.…”

“…It is a closed achronal 37 surface S such that its domain of dependence D (S) is the entire spacetime M. Thus, by knowing the information (e.g. the values of some field) on a Cauchy surface, we are able to predict (and postdict) what happens throughout 33 The 2+1D Minkowski metric in polar coordinates is g µν = diag −1, 1, r 2 . Thus |∂ r | 2 = 1 and ∂ t + 2∂ φ 2 = −1 + 4r 2 > 3 since r > 1 inside the surface.…”