2018/12/31 by Alex Simpson, Matt Visser · 2 citations
Physics and Astronomy · #gr-qc
paper · pdf · doi:10.1088/1475-7516/2019/02/042
published as JCAP 1902 (2019) 042 · 22 pages, 5 figures. One typo fixed; one reference added (for v2). 5 references added, explanation on the null energy condition rewritten for clarity (for v3)
arxiv created 2019/02/03 · arxiv updated 2019/03/01
So-called "regular black holes" are a topic currently of considerable interest in the general relativity and astrophysics communities. Herein we investigate a particularly interesting regular black hole spacetime described by the line element ds2=-(1-\frac2m√r2+a2)dt2+\fracdr21-\frac2m√r2+a2 +(r2+a2)(dθ2+sin2θ dϕ2). This spacetime neatly interpolates between the standard Schwarzschild black hole and the Morris-Thorne traversable wormhole; at intermediate stages passing through a black-bounce (into a future incarnation of the universe), an extremal null-bounce (into a future incarnation of the universe), and a traversable wormhole. As long as the parameter a is non-zero the geometry is everywhere regular, so one has a somewhat unusual form of "regular black hole", where the "origin" r=0 can be either spacelike, null, or timelike. Thus this spacetime generalizes and broadens the class of "regular black holes" beyond those usually considered.