Year of Graduation


Level of Access

Open Access Thesis

Embargo Period


Department or Program

Physics and Astronomy

First Advisor

Thomas Baumgarte


We consider an earlier analysis by Baumgarte and de Oliveira (2022) of static Bona-Massó slices of stationary, nonrotating, uncharged black holes, represented by Schwarzschild spacetimes, and generalize that approach to Reissner-Nordström (RN) spacetimes, representing stationary, nonrotating black holes that carry a nonzero charge. This charge is parametrized by the charge-to-mass ratio λQ/M, where M is the black-hole mass and the charge Q may represent electrical charge or act as a placeholder for extensions of general relativity. We use a height-function approach to construct time-independent, spherically symmetric slices that satisfy a so-called Bona-Massó slicing condition. We compute quantities such as critical points and profiles of geometric quantities for several different versions of the Bona-Massó slicing condition. In some cases we do this analytically, while in others we use numerical root-finding to solve quartic equations. We conclude that in the extremal limit as λ → 1, all slices that we consider approach a unique slice that is independent of the chosen Bona-Massó condition.

We then study dynamical, i.e. time-dependent, Bona-Massó slices by analytically predicting the qualitative behavior of the central lapse, i.e. the lapse at the black-hole puncture, for a particular slice that Alcubierre (1997) proposed to mitigate gauge shocks. These shock-avoiding slices are a viable alternative to the very common so-called 1 + log slices but exhibit different behavior in dynamical simulations. We use a perturbation of the radial coordinate at the location of the puncture to recover approximately harmonic late-time oscillations of the central lapse that Baumgarte and Hilditch (2022) observed in numerical simulations.