Scalar-tensor black holes coupled to Euler-Heisenberg nonlinear electrodynamics

Understand

The no-scalar-hair conjecture rules out the existence of asymptotically flat black holes with a scalar dressing for a large class of theories.

• No-scalar-hair theorems have been proved for the cases of neutral black holes and for charged black holes in the Maxwell electrodynamics.
• These theorems, however, do not apply in the case of non-linear electrodynamics.
• In the present work numerical solutions describing charged black holes coupled to Euler-Heisenberg type non-linear electrodynamics in scalar-tensor theories of gravity with massless scalar field are found.