Possibility of hyperbolic tunneling

Traversable wormholes are primarily useful as “gedanken experiments” and as a theoretician’s probe of the foundations of general relativity. In this work, we analyze the possibility of having tunnels in a hyperbolic spacetime. We obtain exact solutions of static and pseudo-spherically symmetric spacetime tunnels by adding exotic matter to a vacuum solution referred to as a degenerate solution of class A. The physical properties and characteristics of these intriguing solutions are explored, and through the mathematics of embedding it is shown that particular constraints are placed on the shape function, that differ significantly from the Morris-Thorne wormhole. In particular, it is shown that the energy density is always negative, and the radial pressure is positive, at the throat, contrary to the Morris-Thorne counterpart. Specific solutions are also presented by considering several equations of state, and by imposing restricted choices for the shape function or the redshift function.

Figure 1

The embedding diagram of a two-dimensional section along the slice ($t=\mathrm{const}$, $u=u_0={sinh}^{-1}(1)$) of a tunnel in spacetime.