Deflection of light by black holes and massless wormholes in massive gravity

Abstract

Weak gravitational lensing by black holes and wormholes in the context of massive gravity (Bebronne and Tinyakov, JHEP 0904:100, 2009) theory is studied. The particular solution examined is characterized by two integration constants, the mass M and an extra parameter S namely 'scalar charge'. These black hole reduce to the standard Schwarzschild black hole solutions when the scalar charge is zero and the mass is positive. In addition, a parameter λ in the metric characterizes so-called 'hair'. The geodesic equations are used to examine the behavior of the deflection angle in four relevant cases of the parameter λ. Then, by introducing a simple coordinate transformation r λ = S + v 2 into the black hole metric, we were able to find a massless wormhole solution of Einstein-Rosen (ER) (Einstein and Rosen, Phys Rev 43:73, 1935) type with scalar charge S. The programme is then repeated in terms of the Gauss-Bonnet theorem in the weak field limit after a method is established to deal with the angle of deflection using different domains of integration depending on the parameter λ. In particular, we have found new analytical results corresponding to four special cases which generalize the well known deflection angles reported in the literature. Finally, we have established the time delay problem in the spacetime of black holes and wormholes, respectively. a

Shadows of rotating wormholes

“…In this work, we revisit the problem and obtain the complete and correct shapes of the shadows cast by the rotating Teo wormholes. Other than shadows, several other observational aspects of wormholes such as electromagnetic signatures of accretion disks around wormholes [65][66][67], spin precession of a test gyro moving in a rotating wormhole [68], and gravitational lensing [69][70][71][72][73][74][75][76][77][78][79], have been studied in the past. It is also worth mentioning that, although wormholes in general relativity necessarily violate different energy conditions, it is not so in the case of modified gravity wormholes (see [80][81][82][83][84][85][86][87][88][89][90][91][92][93] and references therein for some recent examples).…”

Conical Morris-Thorne wormholes with a global monopole charge

“…While for an alternative method to study gravitational lensing via GBT see the Refs. [82][83][84][85][86][87]. This paper has the following organization.…”

Wormholes with nonexotic matter in Born-Infeld gravity

“…See [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] and references therein for some such examples. Also see [31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46] for some recent works on different aspects of wormholes.…”