Vortex Effects in Merging Black Holes and Saturons

Vorticity has recently been suggested to be a property of highly spinning black holes. The connection between vorticity and limiting spin represents a universal feature shared by objects of maximal microstate entropy, so-called saturons. Using $Q$-ball-like saturons as a laboratory for black holes, we study the collision of two such objects and find that vorticity can have a large impact on the emitted radiation as well as on the charge and angular momentum of the final configuration. As black holes belong to the class of saturons, we expect that the formation of vortices can cause similar effects in black hole mergers, leading to macroscopic deviations in gravitational radiation. This could leave unique signatures detectable with upcoming gravitational-wave searches, which can thereby serve as a portal to macroscopic quantum effects in black holes.

Figure 1

Snapshots of the charge density from the numerical three-dimensional evolution of the merger dynamics for the no-vortex (left two columns) and vortex case (right two columns). Odd columns show the full three-dimensional snapshot, while even columns display the two-dimensional plane clipped at the $Q$-ball centers. In these simulations $\alpha =1$, $\omega =0.4m$, $v_{\text{intial}}=0.25$, and the impact parameter $b=12m^{-1}$.

Figure 2

Energy (upper panel), charge (middle panel), and angular momentum (lower panel) as a function of time for the three cases outlined in the text.