Erik Schnetter <>



Provide periodic boundary conditions.

1 Introduction

This thorn provides periodic boundary conditions that are independent of PUGH, i.e. they work with both PUGH and Carpet. They use the new boundary condition scheme, so that no changes to existing code and only small changes to existing parameter files are necessary. Currently, thorn Periodic works in single patch mode only.

2 Using This Thorn

Make sure that the other symmetry thorns (e.g. CartGrid3D) do not provide symmetry boundary conditions for the same boundaries as Periodic. Then activate thorn Periodic and thorn Slab. Set the parameters Periodic::periodic* according to your wishes.

2.1 Obtaining This Thorn

This thorn (and thorn Slab) are available in the TAT arrangement.

2.2 Examples

The following lines come from a WaveToy simulation with Carpet: