Visualizations

Boson star-black hole binaries: Initial data and head-on collisions

This numerical-relativity animation shows head-on collisions between a boson star and a black hole for mass ratios \(q = M_{\rm BS}/M_{\rm BH} = 0.5\) (left) and \(q = 2\) (right). The colors show the scalar-field amplitude \(\lvert \varphi \rvert\) in the x-y plane, illustrating the disruption and accretion of the boson star during the collision. The red contours mark a constant-conformal-factor surface used as a rough estimate of the horizon location. The color scale adjusts with time to reveal the increasingly dilute scalar field after the collision. Read the corresponding paper (arXiv:2604.15240).

Spontaneous deformation of an AdS spherical black hole

This fully nonlinear simulation follows an unstable spherical black hole in asymptotically anti-de Sitter spacetime. A small axisymmetric perturbation triggers an instability that spontaneously breaks spherical symmetry, producing a deformed, axisymmetric black hole while the external scalar source remains isotropic. The left panel visualizes the evolving apparent horizon, colored by its entropy density relative to the initial state; the right panel compares its meridional profile with the initial spherical configuration. Read the corresponding paper (arXiv:2307.14156).