We use the Møller energy-momentum complex both in general relativity and teleparallel gravity to evaluate energy distribution (due to matter plus fields including gravity) in the dyadosphere region for Reissner-Nordström black hole. We found the same and acceptable energy distribution in these different approaches of the Møller energy-momentum complex. Our teleparallel gravitational result is also independent of the teleparallel dimensionless coupling constant, which means that it is valid in any teleparallel model. This paper sustains (a) the importance of the energy-momentum definitions in the evaluation of the energy distribution of a given space-time and (b) the viewpoint of Lessner that the Møller energy-momentum complex is a powerful concept for energy and momentum.

In order to evaluate the energy distribution (due to matter and fields including gravitation) associated with a space-time model of generalized diagonal metric, we consider the Einstein, Bergmann–Thomson and Landau–Lifshitz energy and/or momentum definitions both in Einstein's theory of general relativity and the teleparallel gravity (the tetrad theory of gravitation). We find same energy distribution using Einstein and Bergmann–Thomson formulations, but we also find that the energy–momentum prescription of Landau–Lifshitz disagree in general with these definitions. We also give eight different well-known space-time models as examples, and considering these models and using our results, we calculate the energy distributions associated with them. Furthermore, we show that for the Bianchi Type-I models all the formulations give the same result. This result agrees with the previous works of Cooperstock–Israelit, Rosen, Johri et al, Banerjee–Sen, Xulu, Vargas and Saltı et al and supports the viewpoints of Albrow and Tryon.

We use the Møller energy–momentum complex both in general relativity and teleparallel gravity to evaluate energy distribution (due to matter plus fields including gravity) in the dyadosphere region for Reissner–Nordström black hole. We found the same and acceptable energy distribution in these different approaches of the Møller energy–momentum complex. Our teleparallel gravitational result is also independent of the teleparallel dimensionless coupling constant, which means that it is valid in any teleparallel model. This paper sustains (a) the importance of the energy–momentum definitions in the evaluation of the energy distribution of a given space–time and (b) the viewpoint of Lessner that the Møller energy–momentum complex is a powerful concept for energy and momentum.

In this study, using the time-like fractal theory of gravity, we mainly focus on the ghost dark energy model which was recently suggested to explain the present acceleration of the cosmic expansion. Next, we establish a connection between the quintessence scalar field and fractal ghost dark energy density. This correspondence allows us to reconstruct the potential and the dynamics of a fractal canonical scalar field (the fractal quintessence) according to the evolution of ghost dark energy density.