The main objective of this work is the construction of regular black hole solutions in the context of the Einstein–Maxwell theory. The strategy is to match an interior regular solution to an exterior electrovacuum solution. With this purpose, we first write explicitly the Einstein field equations for the interior regular region. We take an electrically charged nonisotropic fluid, which presents spherical symmetry and a de Sitter type equation of state, where the radial pressure [Formula: see text] is equal to the negative of energy density [Formula: see text], [Formula: see text]. Then, two solutions for the Einstein equations are built, a regular interior solution for the region with matter satisfying a de Sitter equation of state, and an external solution for the region outside the matter, that corresponds to the Reissner–Nordström metric. To complete the solution we apply the Darmois–Israel junction conditions with a timelike thin shell at the matching surface. It is assumed that the matching surface is composed by a thin shell of matter, i.e. a surface layer in the form of a perfect fluid obeying a barotropic equation of state, [Formula: see text] and [Formula: see text] being the intrinsic pressure and energy density of the shell, respectively, and [Formula: see text] a constant parameter. We show that there are electrically charged regular black hole solutions and other compact objects for specific choices of [Formula: see text] and of the other parameters of the model. Some properties the objects are investigated.
(Anti-) de Sitter electrically charged black-hole solutions in higher-derivative gravity
