“As our island of knowledge grows, so does the shore of our ignorance.” – John Archi ald Wheeler, !""# Gravity theory and GW phenomenology Paolo Pani on behalf of the gravity-theory group web.uniroma!.it$gmunu Several of the deepest questions in fundamental physics involve gravity: The nature of gravity. %s &instein 'still( right) What building-block principles and symmetries in nature invoked y General +elativity 'G+( can e challenged) Are there e,tra fields involved in the gravitational interaction? The nature of neutron stars. How does nuclear matter ehave in the e,treme conditions present in the inner core of neutron stars) /an we learn something on the non-perturbative regime of 0/1) 1oes exotic physics show up in these o jects) The nature of black holes. Are the o jects observed y 3%G4*5irgo really the classical black holes of G+) Are there signatures of 6uantum gravity in the spacetime geometry of these compact o jects) 1o more e,otic species of compact o jects e,ist) The nature of dark matter. %s dark matter composed of particles, dark o jects, or modifications of the gravitational interaction? /an we detect or constrain dark matter y looking at its gravitational interaction with black holes and neutron stars) #$!! Our group: web.uniroma!.it/gmunu 9$!! Our research [keyword cloud by scimeter.org] :$!! Research topics @web.uniroma!.it$gmunu$researchA GW modelling Neutron star physics merger r 0uasinormal modes of NSs i n inspiral g d <ultimessenger constraints of o w the NS equation of state n =idal deformability & GWs Gravity & astroparticles Signatures of ultralight bosons Tests of gravity (e.g., axions) in curved spacetime /ompact objects in modi-ed gravity ?lack-hole superradiance GW signals beyond GR /ompact objects & dark matter ?. ringdown tests of gravity &xotic compact objects B$!! 7ome examples of research projects ;S coalescence: post-merger inspiral point*particle Modelling neutron*star (NS) binaries tidal eCects %nternal structure of a N78 I$!! Dost-Newtonian theory, tidal deformations, NS oscillations, ... GW170817: GW constraints on EoS can be combined with E< ones! ?lack holes '?Hs( eyond GR GR is incomplete8 it should e the first order in a high*curvature e,pansion &xtra fields ?.s can acquire new charges 1ipolar radiation ;ovel ringdown modes ;umerical*relativity simulations (using supercomputers) of a ?. coalescence in modi-ed gravity E$!! GW spectroscopy ?. ringdown is descri ed by a set of quasinormal modes ;o-hair theorem8 quasinormal mode spectrum depends only on mass and spin 2 or more modes: tests of General Relativity! G$!! GW spectroscopy ?. ringdown is descri ed by a set of quasinormal modes ;o-hair theorem8 quasinormal mode spectrum depends only on mass and spin 2 or more modes: tests of General Relativity! .ow to parametrize the ringdown? +ingdown tests with many sources 4vertones, are they important? ;ew physics at the horizon scale? GW echoes from exotic objects ?. spectroscopy G$!! New horizons %ot of exciting work in the years to come! Third-generation (3G! GW detectors: #instein Telescope ;ew theoretical and experimental challenges <em ers of the 3G Science Team $pace mission %&$A (#$A/N'$'! ;ovel sources at low frequency (supermassive B.s, E<+%s, ...( <em er of the L%SA Consortium "$!! Our network <em ers of the Amaldi Research /enter @ 7apienJa <em ers of /47= Action “GWverse”, ;etwork +%7E “StrongGR”, /oordination of =&4;GRA5 %;O; initiative &+/ “DarkGRA” project [www.darkgra.orgA <em ers of the 3%7A /onsortium WPs8 GW modelling, science interpretation, tests of G+ <em ers of the 9G 7cience =eam <em ers of the eP=P 7cience =eam +ain collaborations: 3is on '%7=(, Johns Hopkins U., 7%7SA, =ubingen K., LingMs /ollege, Derimeter %nstitute, ;ottingham, /ambridge, Dalma, ?arcelona... !F$!! Studying gravity @ 7apienza ● “+elatività Generale” 'Drof. Oerrari) R I crediti, 3< ● “4nde gravitazionali, buchi neri, stelle di neutroni” 'Prof. Gualtieri) R I crediti, 3< ● “&xperimental gravitation” 'Prof. Ricci) R I crediti, 3< ● Darticle > Astroparticle physics, %ntroduzione alla gravitQ 6uantistica, ● Astrophysics, /osmology, /ompact objects... “Recording a GW […] has never been a big motivation for L GO, the motivation has always been to open a new window to the Universe& – Lip =horne '??/ interview, #F!I( Backup slides “Nothing is More Necessary than the Unnecessary” [cit.] Merger of two black holes @3%G4*5irgo Colla oration, D+3 !!I, FI!!F# '#F!I(, D+3 !!I, ##!!F! '#F!I(, D+3 !!I, #:!!F# '#F!I(, ...A r i merger n g d inspiral o w n ;uove s-de e domande multidisciplinari8 Astro" rates inarie uchi neri, formaJione uchi neri supermassivi, struttura stelle di neutroni, sorgenti raggi gamma,S Fisica Fondamentale" e6uaJione di stato ultranucleare, veri-che gravitQ, natura uchi neri, materia oscura, ... Merger of two black holes @3%G4*5irgo Colla oration, D+3 !!I, FI!!F# '#F!I(, D+3 !!I, ##!!F! '#F!I(, D+3 !!I, #:!!F# '#F!I(, ...A r i merger n g d inspiral o w n ;uove s-de e domande multidisciplinari8 Astro" rates inarie uchi neri, formaJione uchi neri supermassivi, struttura stelle di neutroni, sorgenti raggi gammaS ,isica Fondamentale" equaJione di stato ultranucleare, veri-che gravitQ, natura uchi neri, materia oscura, ....