Einstein@Home is one of the largest distributed volunteer computing projects in the world and has almost 480,000 participants. Their computers provide a sustained computing power of roughly 9.3 PetaFlop/s. If the project were listed on the Top-500, Einstein@Home would be one of the 25 most powerful computers in the world (in the June 2020 list).
Einstein@Home uses idle computing time donated by volunteers all around the world to search for weak astrophysical signals from spinning neutron stars (also called pulsars). The project analyzes data from the LIGO gravitational-wave detectors, the Arecibo and Parkes radio telescopes, and the Fermi gamma-ray satellite.
Einstein@Home volunteers have already discovered more than 70 new neutron stars, and we hope to find many more in the future. Our long-term goal is to make the first direct detections of gravitational-wave emission from spinning neutron stars. Gravitational waves were predicted by Albert Einstein almost a century ago. In September 2015 gravitational waves from colliding black holes were detected for the first time ever, ushering in a new era in astronomy.
Continuous gravitational waves
Einstein@Home was started in 2005 and since then has been searching for gravitational wave signals from rapidly rotating neutron stars in the data from the LIGO and Virgo detectors. Search runs with improving sensititivity provide increasingly better upper limits on the emission of continuous gravitational waves from a Galactic population of neutron stars.
In spring 2009, Einstein@Home launched a new search for radio pulsars in binary systems using data from the Arecibo Radio Observatory in Puerto Rico. This work was developed at the AEI in Hannover in collaboration with the PALFA collaboration, then led by Prof. Jim Cordes at Cornell. While this search is intended to find new radio pulsars in sub-hour period binary orbits, it is also sensitive to isolated radio pulsars and to radio pulsars in longer period orbits. By late 2016 this search had already discovered 55 previously unknown pulsars. It currently runs on ARM-powered devices with Android and Linux operating systems.
Since mid 2011, Einstein@Home also analyzes data from the Fermi gamma-ray satellite using novel methods initially developed for continuous gravitational-wave searches at the AEI in Hannover. As of September 2019, Einstein@Home has discovered 23 new gamma-ray pulsars. There is also a search for selected gamma-ray pulsars in binary systems which runs on GPUs provided by the project volunteers.
Einstein@Home is a World Year of Physics 2005 and an International Year of Astronomy 2009 project supported by the American Physical Society (APS) and by a number of international organizations.