Editing Einstein@Home (section)

{{Short description|BOINC volunteer computing project that analyzes data from LIGO to detect gravitational waves}}
{{Infobox distributed computing project
| name                    = Einstein@Home
| developer               = [[Max Planck Society]] (MPG)
| released                = {{start date |2005|02|19}}
| operating system        = [[Cross-platform]]
| platform                = [[BOINC]]
| license                 = [[GNU General Public License|GPL-2.0-or-later]]<ref name=lic/>
| status                  = Active
| website                 = {{URL|1=https://einsteinathome.org/}}
| performance             = 7659.0 [[FLOPS|TFLOPS]]<ref name=STATS>{{cite web | title=Einstein@home: Computing Capacity | url=https://einsteinathome.org/server_status.html | access-date=2023-12-08 | archive-date=2023-12-08 | archive-url=https://web.archive.org/web/20231208134452/https://einsteinathome.org/server_status.php | url-status=live }}</ref> (December 2023)
| active users            = 16,069{{r|STATS}}
| total users             = 1,048,317{{r|STATS}}
| active hosts            = 34,751{{r|STATS}}
| total hosts             = 8,140,803{{r|STATS}}
| screenshot              =Einstein@Home.gif|screenshot_size=250px|screenshot caption=Einstein@Home screensaver}}

'''Einstein@Home''' is a [[volunteer computing]] project that searches for signals from spinning neutron stars in data from gravitational-wave detectors, from large radio telescopes, and from a gamma-ray telescope. [[Neutron stars]] are detected by their pulsed [[radio wave|radio]] and [[gamma-ray]] emission as radio and/or gamma-ray [[pulsars]]. They also might be observable as continuous [[gravitational wave]] sources if they are rapidly spinning and non-axisymmetrically deformed. The project was officially launched on 19 February 2005 as part of the [[American Physical Society]]'s contribution to the [[World Year of Physics 2005]] event.<ref name="msnbc">{{cite web|last=Boyle|first=Alan|title=Software sifts through gravity's mysteries|url=http://www.nbcnews.com/id/6998163|access-date=2006-06-03|work=[[NBC News]]|date=19 February 2005 |archive-date=2013-10-12|archive-url=https://web.archive.org/web/20131012053335/http://www.nbcnews.com/id/6998163/|url-status=dead}}</ref>

Einstein@Home searches data from the [[LIGO]] gravitational-wave detectors. The project conducts the most sensitive all-sky searches for continuous gravitational waves. While no such signal has yet been detected, the upper limits set by Einstein@Home analyses provide astrophysical constraints on the Galactic population of spinning neutron stars.

Einstein@Home also searches radio telescope data from the [[Arecibo Observatory]], and has in the past analyzed data from [[Parkes Observatory]]. On 12 August 2010, the first discovery by Einstein@Home of a previously undetected radio pulsar [[PSR J2007+2722|J2007+2722]], found in data from the Arecibo Observatory, was published in ''[[Science (journal)|Science]]''.<ref name=Science20100812>{{cite journal |doi=10.1126/science.1195253|bibcode = 2010Sci...329.1305K | pmid=20705813 | volume=329 |issue=5997 |title=Pulsar discovery by global volunteer computing |date=September 2010 |journal=Science |pages=1305 |vauthors=Knispel B, Allen B, Cordes JM |display-authors=etal |arxiv=1008.2172|s2cid = 29786670 }}</ref><ref name="BBC20100813" /> This was the first data-based discovery by a volunteer computing project. As of December 2023 Einstein@Home had discovered 55 radio pulsars.<ref name=":1">{{Cite web |title=Pulsars research at AEI Hannover |url=https://www.aei.mpg.de/pulsars |url-status=live |archive-url=https://web.archive.org/web/20231211135648/https://www.aei.mpg.de/pulsars |archive-date=2023-12-11 |access-date=2023-12-11 |website=www.aei.mpg.de |language=en }}</ref>

The project also analyses data from the [[Fermi Gamma-ray Space Telescope]] to discover gamma-ray pulsars. On 26 November 2013, the first Einstein@Home results of the Fermi data analysis was published: the discovery of four young gamma-ray pulsars in LAT data.<ref name=":4" /> As of December 2023, Einstein@Home has discovered 39 previously unknown gamma-ray pulsars<ref name=":1" /> in data from the Large Area Telescope on board the Fermi Gamma-ray Space Telescope. The Einstein@Home search makes use of novel and more efficient data-analysis methods and discovered pulsars missed in other analyses of the same data.<ref>{{cite journal |last=Clark |first=Colin J. | display-authors=etal |date=2016 |title=The Einstein@Home Gamma-ray Pulsar Survey I: Search Methods, Sensitivity and Discovery of New Young Gamma-ray Pulsars |arxiv = 1611.01015 |doi=10.3847/1538-4357/834/2/106 |volume=834 |issue=2 |journal=The Astrophysical Journal |page=106|bibcode=2017ApJ...834..106C|s2cid=5750104 |doi-access=free }}</ref><ref name=":0">{{cite web|author1=Einstein@home|date=2020-09-10|title=Tenth anniversary of the first Einstein@Home discovery|url=https://einsteinathome.org/pt-pt/content/tenth-anniversary-first-einsteinhome-discovery|access-date=2020-09-10|website=Einstein@home|archive-date=2022-09-05|archive-url=https://web.archive.org/web/20220905052057/https://einsteinathome.org/pt-pt/content/tenth-anniversary-first-einsteinhome-discovery|url-status=live}}</ref>

The project runs on the [[Berkeley Open Infrastructure for Network Computing|Berkeley Open Infrastructure for Network Computing (BOINC)]] software platform and uses [[free software]] released under the [[GNU General Public License]], version 2.<ref name="lic">{{Cite web |url=http://einsteinathome.org/application-source-code-and-license |title=Einstein@Home application source code and license |access-date=2016-11-17 |archive-date=2016-10-21 |archive-url=https://web.archive.org/web/20161021121710/https://einsteinathome.org/application-source-code-and-license |url-status=live }}</ref> Einstein@Home is hosted by the [[Max Planck Institute for Gravitational Physics|Max Planck Institute for Gravitational Physics (Albert Einstein Institute, Hannover, Germany)]] and the [[University of Wisconsin–Milwaukee]]. The project is supported by the [[Max Planck Society|Max Planck Society (MPG)]], the [[American Physical Society]] (APS), and the US [[National Science Foundation]] (NSF). The Einstein@Home project director is [[Bruce Allen (physicist)|Bruce Allen]].

Einstein@Home uses the power of [[volunteer computing]] in solving the computationally intensive problem of analyzing a large volume of data. Such an approach was pioneered by the [[SETI@home]] project, which is designed to look for signs of extraterrestrial life by analyzing radio wave data. Einstein@Home runs through the same software platform as SETI@home, the [[Berkeley Open Infrastructure for Network Computing|Berkeley Open Infrastructure for Network Computing (BOINC)]]. As of December 2023, more than 492,000 volunteers in 226 countries had participated in the project, making it the third-most-popular active BOINC application.<ref name=":2">{{Cite web |title=Einstein@Home server status page |url=https://einsteinathome.org/server_status.html |url-status=live |archive-url=https://web.archive.org/web/20231208134452/https://einsteinathome.org/server_status.php |archive-date=2023-12-08 |access-date=2023-12-08 |website=einsteinathome.org}}</ref><ref name="boincstats project statistics">{{cite web |title=BOINCstats project statistics |url=https://boinc.mundayweb.com/html/stats.php |url-status=live |archive-url=https://web.archive.org/web/20231208134954/https://boinc.mundayweb.com/html/stats.php |archive-date=2023-12-08 |access-date=2023-12-08}}</ref> Users regularly contribute about 7.7 [[FLOPS|petaFLOPS]] of computational power,<ref name=":2" /> which would rank Einstein@Home among the top 105 on the [[TOP500]] list of [[supercomputer]]s.<ref name="Top500 List - November 2016">{{cite web |title=Top500 List - November 2023 |url=https://www.top500.org/lists/top500/list/2023/11/ |url-status=live |archive-url=https://web.archive.org/web/20231208135228/https://www.top500.org/lists/top500/list/2023/11/ |archive-date=2023-12-08 |access-date=2023-12-08}}</ref>