Piecewise Flat Gravitational Waves

Understand

We examine the continuum limit of the piecewise flat locally finite gravity model introduced by 't Hooft.

• In the linear weak field limit we find the energy--momentum tensor and metric perturbation of an arbitrary configuration of defects.
• The energy--momentum turns out to be restricted to satisfy certain conditions.
• The metric perturbation is mostly fixed by the energy--momentum except for its lightlike modes which reproduce linear gravitational waves, despite no such waves being present at the microscopic level.