2019/02/28 by Alex Simpson, Prado Martin-Moruno, Matt Visser · 1 citation
Physics and Astronomy · #gr-qc
paper · pdf · doi:10.1088/1361-6382/ab28a5
published as Classical and Quantum Gravity 36 # 14 (2019) 145007 · V1: 27 pages; 5 Carter-Penrose diagrams. V2: Two references added. V3: 29 pages; closely matches published version
arxiv created 2019/06/26 · arxiv updated 2019/06/27
We consider a non-static evolving version of the regular "black-bounce"/traversable wormhole geometry recently introduced in JCAP02(2019)042 [arXiv:1812.07114 [gr-qc]]. We first re-write the static metric using Eddington-Finkelstein coordinates, and then allow the mass parameter m to depend on the null time coordinate (a la Vaidya). The spacetime metric is ds2=-(1-\frac2m(w)√r2+a2)dw2-(± 2 dw dr) +(r2+a2)(dθ2+sin2θ dϕ2). Here w=\u,v\ denotes the \outgoing,ingoing\ null time coordinate; representing \retarded,advanced\ time. This spacetime is still simple enough to be tractable, and neatly interpolates between Vaidya spacetime, a black-bounce, and a traversable wormhole. We show how this metric can be used to describe several physical situations of particular interest, including a growing black-bounce, a wormhole to black-bounce transition, and the opposite black-bounce to wormhole transition.