Unveiling the dark universe with gravitational waves: Black holes and compact stars as laboratories for fundamental physics

Projektinformationen

DarkGRA

ID Finanzhilfevereinbarung: 757480

DOI

10.3030/757480

Projekt abgeschlossen

EK-Unterschriftsdatum 28 September 2017

Startdatum 1 Oktober 2017

Enddatum 30 September 2023

Finanziert unter

• EXCELLENT SCIENCE - European Research Council (ERC)

Gesamtkosten

€ 1 337 480,94

EU-Beitrag

€ 1 337 480,94

Koordiniert durch

UNIVERSITA DEGLI STUDI DI ROMA LA SAPIENZA
Italy

Periodic Reporting for period 4 - DarkGRA (Unveiling the dark universe with gravitational waves: Black holes and compact stars as laboratories for fundamental physics)

Berichtszeitraum: 2022-04-01 bis 2023-09-30

Zusammenfassung vom Kontext und den Gesamtzielen des Projekts

The landmark detection of gravitational waves has opened a new era in physics, giving access to the hitherto unexplored strong-gravity regime, where spacetime curvature is extreme and the relevant speeds are close to the speed of light. In parallel to its countless astrophysical applications, this discovery can have also important implication for fundamental physics.

The aim of the DarkGRA* project - funded by the European Research Council (ERC-2017-StG 757480) - is to investigate novel phenomena related to strong gravitational sources such as black holes and neutron stars - that can be used to turn these objects into cosmic labs, where matter in extreme conditions, particle physics, and the very foundations of Einstein's theory of gravity can be put to the test.

We are exploring some outstanding, cross-cutting problems in fundamental physics: the nature of black holes and of spacetime singularities, the limits of classical gravity, the existence of extra light fields, and the effects of dark matter near compact objects.

Arbeit, die ab Beginn des Projekts bis zum Ende des durch den Bericht erfassten Berichtszeitraums geleistet wurde, und die wichtigsten bis dahin erzielten Ergebnisse

A list of the main achievement obtained includes:

- Development of a model-agnostic, analytical template for gravitational-wave echoes, including spin effects
- Repository for echoes: https://www.darkgra.org/gw-echo-catalogue.html
- New constraints on exotic compact objects using the stochastic background in gravitational waves
- Projected constraints on exotic compact objects using the future LISA mission
- Development of a new metric describing deformed objects in General Relativity, publicly available: https://www.darkgra.org/projects.html
- Novel spin-tidal post-Newtonian terms for binary-coalescence waveforms
- Gravitational-wave signatures of spin-1 and spin-2 fields around black holes, projected constraints on ultralight dark matter with present and future detectors
- Simulations of binary black holes in a well-motivated alternative theory of gravity
- Study of anisotropic stars in General Relativity and beyond
- Written a comprehensive Living Review on tests of the nature of compact objects
- Second edition of the "Superradiance" monograph, updated with new tests of ultralight dark matter with gravitational wave observations
- Studies on black-hole spectroscopy with current and future gravitational-wave detectors
- Confrontation of LIGO data with the primordial black hole scenario
- Model independent tests of the Kerr bound with extreme mass ratio inspirals
- New group public repository: https://web.uniroma1.it/gmunu/news/new-groups-git-repository
- First numerical-relativity simulations of the ringdown of a black-hole microstate
- Joined the LISA Consortium as Full Members; work on coordinating some activities within the Consortium
- Joined the Einstein Telescope Collaboration. Coordination activities in the ET Observational Science Board


The main results have been presented at the major conferences in the field, including the GR22/Amaldi13 Conference (invited plenary talk).

Fortschritte, die über den aktuellen Stand der Technik hinausgehen und voraussichtliche potenzielle Auswirkungen (einschließlich der bis dato erzielten sozioökonomischen Auswirkungen und weiter gefassten gesellschaftlichen Auswirkungen des Projekts)

- Include the echo template in a search pipeline to be implemented in current and future searches.
- Explore the phenomenology of deformed compact objects in General Relativity
- Develop new ringdown tests of black holes and other dark objects
- Perform simulations of binary black holes in a non-perturbative theory alternative to General Relativity
- Study extreme mass-ratio inspirals as LISA sources and for parameter estimation and tests of gravity
- Study the detectability of boson star binaries with LISA
- Extend black-hole superradiant instabilities to the spin-2 case
- Confront upcoming LIGO/Virgo data with the primordial black-hole scenario

Examples of gravitational-wave echo waveforms

Embedding diagrams for deformed objects in General Relativity

Constraints on ultralight dark matter from black-hole superradiance and gravitational waves