Bound orbits around Bardeen black holes

A massive particle orbiting around a regular black hole (e.g., a Bardeen one) provides a lot of information about the black hole, allowing one to investigate the problem of spacetime singularities and get an insight into quantum gravity. In the present work, the bound orbits of the particle around the Bardeen black hole have been established by using a taxonomy proposed by Levin and Perez-Giz. It clearly shows that, both in the innermost stable circular orbits (ISCO) and the marginally bound orbits (MBO), the particle's angular momentum and its radial distance decrease with k g(2), where g is a parameter of the Bardeen model and characterizes the monopole charge of a self-gravitating magnetic field described by a nonlinear electrodynamics. In the strong gravitational field, by using the numerical method, a rational number defined by the taxonomy increases with the particle's energy, but the case of the angular momentum is opposite. The periodic motion in the Bardeen black hole has lower energy in comparison to the one in Schwarzschild black hole. It is expected that the Bardeen black hole could be identified by using the method of the taxonomy when more sophisticated observations for detecting black holes can be implemented in the future and it will give us an inspiring answer to the problems of spacetime singularities and quantum gravity. (C) 2020 Elsevier Inc. All rights reserved.