Stationary hyperboloidal slicings with evolved gauge conditions

We analyze stationary slicings of the Schwarzschild spacetime defined by members of the Bona–Massó family of slicing conditions. Our main focus is on the influence of a non-vanishing offset to the trace of the extrinsic curvature, which forbids the existence of standard Cauchy foliations but at the same time allows gauge choices that are adapted to include null infinity in the evolution. These hyperboloidal slicings are especially interesting for observing outgoing gravitational waves. We show that the standard 1+log slicing condition admits no overall regular hyperboloidal slicing, but by appropriately combining with harmonic slicing, we construct a gauge condition that leads to a strongly singularity-avoiding hyperboloidal foliation that connects the black hole to .