A note on singular and non-singular black holes

Understand

An attempt is made in order to clarify the so called regular black holes issue.

• It is revisited that if one works within General Relativity minimally coupled with non linear source, mainly of electromagnetic origin, and within a static spherically symmetric ansatz for the metric, there is still room for singular contribution to the black hole solution.
• A reconstruction method is proposed and several examples are discussed, including new ones.
• A possible way to obtain a non singular black hole is introduced, and in this case, several known examples are re-discussed, and new ones are provided.