WG6: Gravitational waves

Contacts | Objectives |Tasks | Milestones | Members | Talks | Related works


Group Leader: Tanja Hinderer (University of Amsterdam, Netherlands)
Group Vice-Leader: Germano Nardini (University of Stavanger, Norway)

Objectives (SHARED WITH WG3, WG4 AND WG5)

To analyze the current state of the art of the experimental astronomy of each type of cosmic messenger with respect to the Action’s challenge and identify opportunities for improving the analysis strategies which are currently being followed, in the light of the theoretical frameworks and considerations of WG1 and WG2. To provide WG1 and WG2 with the technical details related to the detection of each type of astrophysical messenger, which need to be considered for a correct phenomenological and theoretical interpretation of the experimental results. To develop new analysis strategies that combine the observations of gamma rays, cosmic rays, neutrinos and gravitational waves for the search of quantum gravity signatures in the framework of multi-messenger astronomy. These new
strategies should be developed in close cooperation with WG1 and specially with WG2. Finally, these WGs will transfer the Action’s motivations, progress and results, to their respective communities of experimentalists to promote their interest on the Action’s challenge.


WG6 will aim to further constrain possible deviations from the post-Newtonian description of binary inspiral, eventually down to the sub-percent level, by combining information from tens to hundreds
of GW sources. Continued GW dispersion measurements will lead to increasingly better bounds on local Lorentz invariance violations and on the mass of the graviton. However, qualitatively new tests of GR
and of the black hole nature of massive compact objects will become possible during the timespan of the Action. Anomalous tidal effects during the late inspiral of presumed binary black holes would be
indicative of “black hole mimickers”. For example, if dark matter consists of fermionic particles then they may form dense stars, which if present in a binary system would betray their nature by the presence of tides. Next, the remnant object resulting from the merger of two compact bodies will undergo “ringdown” as it asymptotes to a quiet state. The associated GW signal involves characteristic frequencies and timescales which for standard black holes should only depend on mass and spin, as a result of the black
hole no-hair theorem. Deviations from this would be tell-tale signs of a horizon modification, or of an entirely different kind of object having formed. Finally, prompted by Hawking’s information paradox, some have proposed macroscopic quantum modifications of black hole structure (“firewalls” and “fuzzballs”), which would lead to GW “echoes” being emitted after the ringdown signal has died down. Though the above is GW-focused, we note the value of a multi-messenger approach: for example,
should an electromagnetic counterpart be seen to a binary merger in the black hole mass range, then this will be a further indication of new physics, and it would help elucidate the nature of black hole mimickers.


  • Year 1: Computational optimization of analyses of binary merger dynamics, and of searches for anomalous GW propagation.
  • Year 2: Development of concrete data analysis tools to search for anomalous tidal effects during inspiral, tests of the no-hair theorem, and GW echoes.
  • Year 3: Formulation of a comprehensive multi-messenger framework to search for black hole mimickers.
  • Year 4: Application of the resulting analysis tools to detections made with Advanced LIGO and Advanced Virgo at final design sensitivity.

Joint WG3-WG4-WG5-WG6 deliverables and activities

  • Publicly available web page with results of LIV studies based on each cosmic messenger.
  • Optimal strategy and method for performing LIV studies (including future experiments and a multi-messenger approach).
  • Publications, and contributions to conferences.
  • Contributions to the communication and outreach activities.
  • Organization of regular video conferences
  • Organization of workshops for specific topics involving also WG1-2


Aaron HeldImperial College LondonUK
Adrian OttewillUniversity College DublinIreland
Alex NielsenUniversity of StavangerNorway
Alicia M. SintesUniversitat de les Illes BalearsSpain
Andrew MillerUniversité catholique de LouvainBelgium
Angelo RicciardoneINFN – Sezione di PadovaItaly
Antoni Ramos BuadesUniversidad de las Islas BalearesSpain
Antonia FrassinoUniversity of BarcelonaSpain
Antonino MarcianòINFN Frascati LNFItaly
Anupam MazumdarVan Swinderen Institute, University of GroningenNetherlands
Anuradha SamajdarNikhefNetherlands
Archisman GhoshNikhefNetherlands
Astrid EichhornCP3-Origins, Univ. of Southern Denmark, and Heidelberg Univ.Germany
Aurora ClericiUniversity of Nova GoricaSlovenia
Banafshe ShiralilouLeiden UniversityNetherlands
Bo-Qiang MaPeking UniversityChina
Carlos F. SopuertaInstitute of Space Sciences (ICE, CSIC), Campus UAB, and Institute of Space Studies of Catalonia (IEEC)Spain
Carlos HerdeiroIST-LisbonPortugal
Cecília NagySzeged UniversityHungary
Celia Escamilla-RiveraICN-UNAMMexico
Chad FinleyStockholm University Sweden
Charalampos TzerefosNational and Kapodistrian University of AthensGreece
Chris van der BroeckNIKHEFNetherlands
Christian PfeiferZARM, University of BremenGermany
Daniel KerszbergIFAE BarcelonaSpain
David BenistyBen Gurion U. of NegevIsrael
Deepak EappachenRadboud UniversityNetherlands
Denitsa StaicovaInstitute for Nuclear Research and Nuclear Energy, BASBulgaria
Diego Blas King’s College LondonUK
Eduardo GuendelmanBen Gurion U. of NegevIsrael
Eleanor HamiltonUniversity of ZurichSwitzerland
Elias C. VagenasKuwait UniversityKuwait
Elvis BarakovicUniversity of TuzlaBosnia and Herzegovina
Emil NissimovInstitute for Nuclear Research and Nuclear Energy, BASBulgaria
Emmanuel N. SaridakisNational Technical University of AthensGreece
Eugene LimKing’s College LondonUK
Fabian SchüsslerIRFU / CEA Paris-SaclayFrance
Federico UrbanCEICO, Institute of Physics (FZU), PragueCzech Republic
Francesco SalamidaUniversity of L’Aquila and INFN LNGSItaly
Gareth DaviesInstituto Galego de Física de Altas Enerxías (IGFAE)Spain
Germano NardiniUniversity of StavangerNorway
Gianluca CalcagniInstituto de Estructura de la Materia, CSICSpain
Giovanni Amelino-CameliaUniversity of NaplesItaly
Günter SiglUniversität HamburgGermany
Helvi WitekKing’s College LondonUK
Ido Ben-DayanAriel UniversityIsrael
Jackson Levi SaidInstitution of Space Sciences and Astronomy (ISSA)Malta
Jan-Willem van HoltenLeiden UniversityNetherlands
John EllisKing’s College LondonUK
John VeitchUniversity of GlasgowUK
Jose Antonio FontUniversidad de ValenciaSpain
Jose Juan Blanco-PilladoUniversidad del País VascoSpain
José Manuel CarmonaUniversidad de ZaragozaSpain
Jose Maria DiegoCantabria Inst. of Phys.Spain
Julien BolmontMontpellier UniversityFrance
László Árpád GergelySzeged UniversityHungary
Laurentiu CarameteISS (Institute of Space Science)Romania
Leanne DurkanUCDIreland
Leïla HaegelAPC Laboratory – University Paris-DiderotFrance
Lucia Aurelia PopaISS (Institute of Space Science)Romania
Mairi SakellariadouKing’s College LondonUK
Maja BuricUniversity of BelgradeSerbia
Manel MartinezIFAE BarcelonaSpain
Manuel AsoreyUniversidad de ZaragozaSpain
Marco de CesareUniversity of the Basque Country UPV/EHUSpain
Marco GiammarchiMilano University and INFNItaly
Maria HaneyUniversity of ZurichSwitzerland
Mario Martinez-PerezIFAE BarcelonaSpain
Mauro PieroniImperial College LondonUK
Michael PürrerAlbert Einstein Institute Potsdam-GolmGermany
Mihnea PopescuISS (Institute of Space Science)Romania
Nicolas YunesUniversity of Illinois at Urbana-ChampaignUSA
Niels A.J. ObersNiels Bohr InstituteDenmark
Nikla KonjikUniversity of BelgradeSerbia
Nikolaos StergioulasAristotle University of ThessalonikiGreece
Ofek BirnholtzBar-Ilan University, Ramat-GanIsrael
Otto HannukselaNikhefNetherlands
Paolo MarcocciaUniversity of StavangerNorway
Pasquale BossoUniversity of LethbridgeMexico
Paulo MonizUniversidade da Beira InteriorPortugal
Pawan GuptaNikhefNetherlands
Peter JonkerRadboud UniversityNetherlands
Peter TaylorDublin City UniversityIreland
Petr TinyakovUniversite Libre de BruxellesBelgium
Philippe JetzerUniversity of ZurichSwitzerland
Pratika DayalUniversity of GroningenNetherlands
Rodrigo Gracia RuizIPHC lab, StrasbourgFrance
Roman PasechnikLund universitySweden
Sachiko KuroyanagiIFT Madrid / Nagoya UniversitySpain
Saeed RastgooYork UniversityCanada
Samaya NissankeUniversity of AmsterdamNetherlands
Sascha HusaUniversidad de las Islas BalearesSpain
Saurya DasUniversity of LethbridgeCanada
Sebastian BahamondeTartu UniversityEstonia
Sébastien ClesseULB, BrusselsBelgium
Selma de MinkUniversity of AmsterdamNetherlands
Spyros BasilakosResearch Center for Astronomy & Applied Mathematics, Academy of Athens, and National Observatory of AthensGreece
Suvodip MukherjeeUniversity of AmsterdamNetherlands
Tanja HindererUniversity of AmsterdamNetherlands
Thierry PradierUniversité de Strasbourg, CNRSFrance
Thomas DentInstituto Galego de Física de Altas Enerxías (IGFAE)Spain
Thomas SotiriouUniversity of NottinghamUK
Thomas ThiemannFriedrich-Alexander-University Erlangen-NuernbergGermany
Tsvi PiranThe Hebrew UniversityIsrael
Vedad PasicUniversity of TuzlaBosnia and Herzegovina
Yaser TavakoliUniversity of GuilanIran
Zakaria BelkhadriaUniversity of CagliariItaly
Zoltan KeresztesSzeged UniversityHungary
Zuzanna Kostrzewa-RutkowskaSRONNetherlands