The Einstein Toolkit is a community driven, open source, free framework to study relativistic astrophysics problems using computer simulations. It is used by many groups, spanning all continents (with the exception of Antarctica), and developed in a distributed, collaborative manner.
We use the Einstein Toolkit for large scale simulation campaigns to study the gravitational waves emitted when two black holes orbit each other, spiral inwards and eventually merge. We use information from these simulations to create models for gravitational waveforms that are then used by scientists in LIGO to search for signals of merging black holes in LIGO’s data stream.
We are also very active in improving and extending the toolkit by optimizing its code, porting to new architectures, adding new physics to it and by contribution tools and utilities to handle simulation campaigns.