TwoPunctures Initial Data

TwoPunctures (GRChombo)

The TwoPunctures repository originates from the standalone TwoPunctures code which in turn comes from the original Einstein Toolkit thorn TwoPunctures.

It has been modified to allow integration with GRChombo.

Physics

The code creates Bowen-York initial data for two puncture black holes using a single domain spectral method. The method is described in Marcus Ansorg, Bernd Brügmann, Wolfgang Tichy, "A single-domain spectral method for black hole puncture data" PRD 70, 064011 (2004) (arXiv:gr-qc/0404056).

Using TwoPunctures initial data with the BBH example

To build this example with TwoPunctures initial data, set the environment variable TWOPUNCTURES_SOURCE to the Source subdirectory of the local clone of the TwoPunctures repository e.g.

export TWOPUNCTURES_SOURCE=/path/to/TwoPunctures/Source

Then, use make to build the all-tp target using a command such as

make all-tp -j 4

The created executable will have the filename

Main_BinaryBH_TP.<config>.ex

To stop using TwoPunctures, undefine the TWOPUNCTURES_SOURCE environment variable:

unset TWOPUNCTURES_SOURCE

Alternatively, you can avoid defining an environment variable by defining it in the make command:

make all-tp -j 4 TWOPUNCTURES_SOURCE=/path/to/TwoPunctures/Source

Note that the parameter names for TwoPunctures initial data differ to that of the vanilla example: see params_two_punctures.txt for the parameter names.