Could the black hole singularity be a field singularity?

Understand

In the wake of interest to find black hole solutions with scalar hair, we investigate the effects of disformal transformations on static spherically symmetric space-times with a non-trivial scalar field.

• In particular, we study solutions that have a singularity in a given frame, while the action is regular.
• We ask if there exists a different choice of field variables such that the geometry and the fields are regular.
• We find that in some cases disformal transformations can remove a singularity from the geometry or introduce a new horizon.