On the Random Motion of Nuclear Objects in a Fuzzy Dark Matter Halo

Understand

Fuzzy Dark Matter (FDM), consisting of ultralight bosons ($m_{\rm b} \sim 10^{-22}\ \rm eV$), is an intriguing alternative to Cold Dark Matter.

• Numerical simulations that solve the Schr\"odinger-Poisson (SP) equation show that FDM halos consist of a central solitonic core, which is the ground state of the SP equation, surrounded by an envelope of interfering excited states.
• These excited states also interfere with the soliton, causing it to oscillate and execute a confined random walk with respect to the halo center of mass.
• Using high-resolution numerical simulations of a $6.6 \times 10^9 M_{\odot}$ FDM halo with $m_{\rm b} = 8 \times 10^{-23}\ \rm eV$ in isolation, we demonstrate that the wobbling, oscillating soliton gravitationally perturbs nuclear objects, such as supermassive black holes or dense star clusters, causing them to diffuse outwards.