Magnetic Hair and Reconnection in Black Hole Magnetospheres

Understand

The no-hair theorem of general relativity states that isolated black holes are characterized by three parameters: mass, spin, and charge.

• In this Letter we consider Kerr black holes endowed with highly magnetized plasma-filled magnetospheres.
• Using general relativistic kinetic plasma and resistive magnetohydrodynamics simulations, we show that a dipole magnetic field on the event horizon opens into a split-monopole and reconnects in a plasmoid-unstable current-sheet.
• The no-hair theorem is satisfied, in the sense that all components of the stress-energy tensor decay exponentially in time.