No abstract

No abstract

The present work is devoted to studying the dynamical evolution of galaxies in scalar-Gauss-Bonnet gravity and its relationship with the MOND paradigm. This study is useful for giving meaning to the presence of a new gravitational constant. The stability of dark matter is strongly dependent on matter density. We are interested in calculating the maximum rotational velocity of galaxies. We show that rotating galaxies can be described by a new parameter that depends both on the minimum value of scalar fields and on the effective mass of this field. According to observational data, we have shown that this parameter is a constant.

No abstract

In this paper, we present a technique to unify the Reissner–Nordstr¨om metric and the Kerr–Newman metric. We construct a specifific model and calculate the entanglement entropy of black horizon. We are interested in the entangled particle and antiparticle spinning on the black hole horizon. The two Reissner-Nordstr¨om horizons r±, are the results of the rotation of several entangled particle-antiparticle on the real horizon. The energy absorbed by a black hole is transformed into a kinetic energy of the entangled particle-antiparticles. This study provides a new type of black hole metric. We show that the rotation of an entangled system of a particle and an antiparticle can create a extremal black hole. We also explore some of the implications of this point of view for the black hole entanglement.