Geodesic Structure of Janis-Newman-Winicour Space-time

Abstract

In the present paper we study the geodesic structure of the Janis-Newman-Winicour(JNW) space-time which contains a strong curvature naked singularity. This metric is an extension of the Schwarzschild geometry when a massless scalar field is included. We find that the strength parameter µ of the scalar field effects on the geodesic structure of the JNW space-time. By solving the geodesic equation and analyzing the behavior of effective potential, we investigate all geodesic types of the test particle and the photon in the JNW space-time. At the same time we simulate all the geodesic orbits corresponding to the energy levels of the effective potential in the JNW space-time.

Accretion processes for general spherically symmetric compact objects

“…The Janis-NewmanWinicour (JNW) solution is obtained as an extension of the Schwarzschild space-time when a massless scalar field (with vanishing potential) is introduced. Thus this solution is not a vacuum solution [24]. Here the coordinate singularity in the Schwarzschild space-time becomes a naked singularity in JNW space-time.…”

Kasner-type singularities and solitons with Lifshitz asymptotics

“…For spacetimes with β i > β 0 for some direction i, there is another infinite barrier at u = u 0 for time-like and null particles. This is reminiscent of geodesics in the Fisher/Janis-Newman-Winicour spacetime where an infinite barrier also appears to particles with non-zero angular momentum if the scalar field supporting the solution is sufficiently strong [43][44][45][46]. We have focused on geodesics in the Lifshitz soliton spacetime, partly because this is an interesting case which is free from curvature singularities, and thus seems more physically relevant.…”

“…We can also see which parameter values require a phantom scalar by checking if ξ is negative in Eq. (43). In Fig.…”

“…Therefore the boundary of this shaded region is where ξ = ξ * . There are three special points marking the values (43). The two circular points correspond to the regular Lifshitz (or AdS) solitons.…”

Time-like geodesic structure in massive gravity

“…Zhou et al [14] analyzed the effective of massless and massive test particles in Bardeen spacetime and numerically simulated all possible orbits corresponding to all kinds of energy levels. And he also investigated all geodesic types of the test particle and the photon in JNW spacetime by solving the geodesic equation and analyzing the behavior of effective potential [15].…”