General Relativistic Astrophysics
Lead Research Organisation:
University of Southampton
Department Name: Sch of Mathematical Sciences
Abstract
We are entering an era of high-precision astronomy, both electromagnetic and gravitational. The first generation of highly sensitive gravitational-wave detectors have reached design sensitivity and are being upgraded using advanced technology. LOFAR is on-line, providing significant improvements in radio timing precision. Future advances associated with the SKA in radio, the Einstein Telescope and the space based detector eLISA for gravitational waves will complement current quality X-ray observations, and will allow us to improve our understanding of the Universe significantly. To benefit maximally from these improvements, we need to improve our current models of a range of phenomena involving compact objects. Better quality theory is needed both to detect the various signals and to probe as much of the relevant physics as possible.
This research proposal builds on the Southampton Gravity Group's expertise in black hole, neutron star and gravitational-wave astrophysics, and is aimed at developing a deeper understanding of the dynamics of black holes and neutron stars, the associated observational signatures and how these signals can be used to provide information about the involved physics. The programme is of a highly interconnected nature with four different themes requiring similar methodology (e.g. general relativistic perturbation theory or numerical simulations) and physics input (e.g. superfluidity, magnetic fields or gravitational radiation reaction). The overall aim is to develop significantly improved models that can be tested against future high-precision observations in a range of channels.
Neutron stars are unique astrophysical laboratories, the modelling of which requires much poorly known physics. In order to investigate their properties, one must combine supranuclear physics with magnetohydrodynamics, a description of superfluids and superconductors, potentially exotic phases of matter like a deconfined quark-gluon plasma and, of course, general relativity. Achieving a better understanding of neutron star dynamics is one of the key aims of this proposal. We will carry out three projects, focused on the dynamics and evolution of neutron stars. The proposed work is of immediate relevance for gravitational-wave physics, leading to astrophysically motivated signal searches, and provides useful insights into problems relevant for electromagnetic observations. We aim to construct accurate models of neutron star dynamics that can be tested against recent observations of oscillations associated with magnetar giant flares, and which will inform future targeted searches for r-mode oscillations in fast spinning neutron stars. We will provide improved models of the enigmatic glitches and other timing phenomena seen in radio pulsars. We also plan to carry out nonlinear simulations of neutron star mergers with an unprecedented level of realism, exploring electromagnetic counterparts to the emerging gravitational waves.
Inspiralling binaries are intrinsically the strongest sources of gravitational waves in the Universe. Gravitational waveforms from such events are extremely efficient probes of the strong gravity near black holes, and their detection promises to allow accurate tests of gravitational theory in its most extreme domain. In order to realise this promise we need a good theoretical understanding of relativistic radiation-reaction effects. Recent progress on the problem of the gravitational self-force provides significant momentum for work in this area. Building on this, we will explore the promising synergy between self-force calculations, numerical relativity and post-Newtonian theory, in order to inform a universal model of binary inspirals across the entire range of mass ratios and spin rates.
This research proposal builds on the Southampton Gravity Group's expertise in black hole, neutron star and gravitational-wave astrophysics, and is aimed at developing a deeper understanding of the dynamics of black holes and neutron stars, the associated observational signatures and how these signals can be used to provide information about the involved physics. The programme is of a highly interconnected nature with four different themes requiring similar methodology (e.g. general relativistic perturbation theory or numerical simulations) and physics input (e.g. superfluidity, magnetic fields or gravitational radiation reaction). The overall aim is to develop significantly improved models that can be tested against future high-precision observations in a range of channels.
Neutron stars are unique astrophysical laboratories, the modelling of which requires much poorly known physics. In order to investigate their properties, one must combine supranuclear physics with magnetohydrodynamics, a description of superfluids and superconductors, potentially exotic phases of matter like a deconfined quark-gluon plasma and, of course, general relativity. Achieving a better understanding of neutron star dynamics is one of the key aims of this proposal. We will carry out three projects, focused on the dynamics and evolution of neutron stars. The proposed work is of immediate relevance for gravitational-wave physics, leading to astrophysically motivated signal searches, and provides useful insights into problems relevant for electromagnetic observations. We aim to construct accurate models of neutron star dynamics that can be tested against recent observations of oscillations associated with magnetar giant flares, and which will inform future targeted searches for r-mode oscillations in fast spinning neutron stars. We will provide improved models of the enigmatic glitches and other timing phenomena seen in radio pulsars. We also plan to carry out nonlinear simulations of neutron star mergers with an unprecedented level of realism, exploring electromagnetic counterparts to the emerging gravitational waves.
Inspiralling binaries are intrinsically the strongest sources of gravitational waves in the Universe. Gravitational waveforms from such events are extremely efficient probes of the strong gravity near black holes, and their detection promises to allow accurate tests of gravitational theory in its most extreme domain. In order to realise this promise we need a good theoretical understanding of relativistic radiation-reaction effects. Recent progress on the problem of the gravitational self-force provides significant momentum for work in this area. Building on this, we will explore the promising synergy between self-force calculations, numerical relativity and post-Newtonian theory, in order to inform a universal model of binary inspirals across the entire range of mass ratios and spin rates.
Planned Impact
This summary identifies some of the routes by which our astrophysics research programme will impact upon the wider world, including the general public, other scientific disciplines, and the technology sector.
COMMUNICATIONS AND ENGAGEMENT: The Southampton Gravity Group has a consistent track record of engaging with the public to communicate the latest and most exciting aspects of its research. These have included public talks, lectures to school students, coordination of a Royal Society Summer Exhibition and contact with Members of Parliament. The Group plans to enhance this activity, with STFC-funded researchers playing a leading role in exploring new dissemination outlets, including "Meet the Astronomer" sessions and the construction of interview/video clips for electronic circulation. The most exciting research advances will be promoted via the University Press office, whose help in publicising recent breakthroughs played a role in several articles on Southampton research appearing in the press, including in National Geographic, New Scientist and The Daily Mail.
COLLABORATION: The richness of the physics needed to model compact objects naturally leads to the possibility of developing collaborations with traditionally disparate scientific disciplines. In particular, there is scope for collaboration with experts in low-temperature physics, whose knowledge of condensed matter many prove invaluable in understanding neutron star interiors. Equally exciting is the possibility of exploiting links between the black hole inspiral problem and the problem of nonlinear electromagnetic pulse propagation in an optical fibre. Steps will be taken to explore these exciting overlaps, which will include the organisation of focused study groups to explore the key issues.
EXPLOITATION AND APPLICATION: The theoretical work of the Group is intimately linked to several large experimental efforts, whose innovative technological development impacts on industry, with spin-offs including satellite stabilisation systems, seismic isolation, the construction of large vacuum cavities, and laser stabilisation. As well as providing motivation for these efforts, the theoretical modelling of the Group is crucial in making informed decisions as to how changes in expenditure and project duration impact on science capabilities.
CAPABILITY AND RESOURCE: We are rapidly approaching an era of precision astronomy, with new electromagnetic and gravitational experimental projects under rapid development. The young researchers that the Group hopes to recruit will receive training in exploiting these opportunities that few other groups could provide. Previous Group members have already gone on to secure prestigious academic appointments. Beyond the world of academia, the skill sets that the researchers would acquire would also equip them to play important roles in the wider community, as is reflected in the success of previous members in gaining attractive jobs in industry. The University recently established a Research Development and Graduate Centre that will help systematize this training, and enable the Group to continue to produce well-rounded researchers with skills well suited to demands of the 21st Century economy and academia.
COMMUNICATIONS AND ENGAGEMENT: The Southampton Gravity Group has a consistent track record of engaging with the public to communicate the latest and most exciting aspects of its research. These have included public talks, lectures to school students, coordination of a Royal Society Summer Exhibition and contact with Members of Parliament. The Group plans to enhance this activity, with STFC-funded researchers playing a leading role in exploring new dissemination outlets, including "Meet the Astronomer" sessions and the construction of interview/video clips for electronic circulation. The most exciting research advances will be promoted via the University Press office, whose help in publicising recent breakthroughs played a role in several articles on Southampton research appearing in the press, including in National Geographic, New Scientist and The Daily Mail.
COLLABORATION: The richness of the physics needed to model compact objects naturally leads to the possibility of developing collaborations with traditionally disparate scientific disciplines. In particular, there is scope for collaboration with experts in low-temperature physics, whose knowledge of condensed matter many prove invaluable in understanding neutron star interiors. Equally exciting is the possibility of exploiting links between the black hole inspiral problem and the problem of nonlinear electromagnetic pulse propagation in an optical fibre. Steps will be taken to explore these exciting overlaps, which will include the organisation of focused study groups to explore the key issues.
EXPLOITATION AND APPLICATION: The theoretical work of the Group is intimately linked to several large experimental efforts, whose innovative technological development impacts on industry, with spin-offs including satellite stabilisation systems, seismic isolation, the construction of large vacuum cavities, and laser stabilisation. As well as providing motivation for these efforts, the theoretical modelling of the Group is crucial in making informed decisions as to how changes in expenditure and project duration impact on science capabilities.
CAPABILITY AND RESOURCE: We are rapidly approaching an era of precision astronomy, with new electromagnetic and gravitational experimental projects under rapid development. The young researchers that the Group hopes to recruit will receive training in exploiting these opportunities that few other groups could provide. Previous Group members have already gone on to secure prestigious academic appointments. Beyond the world of academia, the skill sets that the researchers would acquire would also equip them to play important roles in the wider community, as is reflected in the success of previous members in gaining attractive jobs in industry. The University recently established a Research Development and Graduate Centre that will help systematize this training, and enable the Group to continue to produce well-rounded researchers with skills well suited to demands of the 21st Century economy and academia.
Organisations
- University of Southampton (Lead Research Organisation)
- Max Planck Society (Collaboration)
- California Institute of Technology (Collaboration)
- Cardiff University (Collaboration)
- Indian Initiative in Gravitational-wave Observations (Collaboration)
- UNIVERSITY OF GLASGOW (Collaboration)
- UNIVERSITY OF BIRMINGHAM (Collaboration)
- Massachusetts Institute of Technology (Collaboration)
Publications
Hebbar P
(2020)
X-ray spectral analysis of the neutron star in SNR 1E 0102.2-7219
in Monthly Notices of the Royal Astronomical Society
Gundlach Carsten
(2017)
Critical gravitational collapse with angular momentum II: soft equations of state
in ArXiv e-prints
Gundlach C
(2017)
Einstein-Vlasov system in spherical symmetry. II. Spherical perturbations of static solutions
in Physical Review D
Gundlach C
(2018)
Critical gravitational collapse with angular momentum. II. Soft equations of state
in Physical Review D
Gundlach C
(2020)
Rigidly rotating perfect fluid stars in 2 + 1 dimensions
in Physical Review D
Graber V
(2015)
Magnetic field evolution in superconducting neutron stars
in Monthly Notices of the Royal Astronomical Society
Graber V
(2017)
Neutron stars in the laboratory
in International Journal of Modern Physics D
Gittins F
(2019)
Population synthesis of accreting neutron stars emitting gravitational waves
in Monthly Notices of the Royal Astronomical Society
Dionysopoulou K
(2015)
General-relativistic resistive-magnetohydrodynamic simulations of binary neutron stars
in Physical Review D
Colleoni M
(2015)
Self-force as a cosmic censor in the Kerr overspinning problem
in Physical Review D
Collaboration T
(2017)
All-sky search for long-duration gravitational wave transients in the first Advanced LIGO observing run
in ArXiv e-prints
Collaboration T
(2021)
Constraints on cosmic strings using data from the third Advanced LIGO-Virgo observing run
in arXiv e-prints
Collaboration T
(2017)
First narrow-band search for continuous gravitational waves from known pulsars in advanced detector data
in ArXiv e-prints
Collaboration T
(2018)
Full Band All-sky Search for Periodic Gravitational Waves in the O1 LIGO Data
in ArXiv e-prints
Collaboration T
(2020)
Population Properties of Compact Objects from the Second LIGO-Virgo Gravitational-Wave Transient Catalog
in arXiv e-prints
Collaboration T
(2020)
All-sky search in early O3 LIGO data for continuous gravitational-wave signals from unknown neutron stars in binary systems
in arXiv e-prints
Collaboration T
(2020)
GW190412: Observation of a Binary-Black-Hole Coalescence with Asymmetric Masses
in arXiv e-prints
Collaboration T
(2017)
Upper Limits on Gravitational Waves from Scorpius X-1 from a Model-Based Cross-Correlation Search in Advanced LIGO Data
in ArXiv e-prints
Collaboration T
(2021)
Upper Limits on the Isotropic Gravitational-Wave Background from Advanced LIGO's and Advanced Virgo's Third Observing Run
in arXiv e-prints
Collaboration T
(2020)
Diving below the spin-down limit: Constraints on gravitational waves from the energetic young pulsar PSR J0537-6910
in arXiv e-prints
Collaboration T
(2020)
Search for Gravitational Waves Associated with Gamma-Ray Bursts Detected by Fermi and Swift During the LIGO-Virgo Run O3a
in arXiv e-prints
Collaboration T
(2020)
Tests of General Relativity with Binary Black Holes from the second LIGO-Virgo Gravitational-Wave Transient Catalog
in arXiv e-prints
Coe M. J.
(2017)
PSR J2032+4127/MT91 213 on approach to periastron: X-ray & optical monitoring
in The Astronomer's Telegram
Celora Thomas
(2020)
Linearizing a Non-linear Formulation for General Relativistic Dissipative Fluids
in arXiv e-prints
Celora T
(2021)
Linearizing a non-linear formulation for general relativistic dissipative fluids
in Classical and Quantum Gravity
Brown R
(2019)
Modelling the observable behaviour of SXP 5.05
in Monthly Notices of the Royal Astronomical Society
Brown R
(2018)
Simulating the X-ray luminosity of Be X-ray binaries: the case for black holes versus neutron stars
in Monthly Notices of the Royal Astronomical Society
Brown R
(2019)
Modelling the observable behaviour of SXP 5.05
Brandt Steven R.
(2020)
The Einstein Toolkit
in Zenodo
Barack L
(2017)
Time-domain metric reconstruction for self-force applications
in Physical Review D
Ashton Gregory
(2018)
Advances in our understanding of the free precession candidate PSR B1828-11
in ArXiv e-prints
Ashton G
(2017)
Statistical characterization of pulsar glitches and their potential impact on searches for continuous gravitational waves
in Physical Review D
Ashton G
(2018)
Advances in our understanding of the free precession candidate PSR B1828-11
in Proceedings of the International Astronomical Union
Ashton G
(2018)
A semicoherent glitch-robust continuous-gravitational-wave search method
in Physical Review D
Ashton G
(2016)
Comparing models of the periodic variations in spin-down and beamwidth for PSR B1828-11
in Monthly Notices of the Royal Astronomical Society
Antonopoulou D
(2018)
Pulsar spin-down: the glitch-dominated rotation of PSR J0537-6910
in Monthly Notices of the Royal Astronomical Society
Andersson N.
(2020)
Relativistic fluid dynamics: physics for many different scales
in arXiv e-prints
Andersson N.
(2017)
The enigmatic spin evolution of PSR J0537-6910: r-modes, gravitational waves and the case for continued timing
in ArXiv e-prints
Andersson N.
(2021)
The phenomenology of dynamical neutron star tides
in Monthly Notices of the Royal Astronomical Society
Andersson N
(2016)
A variational approach to resistive relativistic plasmas
Andersson N
(2018)
The Enigmatic Spin Evolution of PSR J0537-6910: r-modes, Gravitational Waves, and the Case for Continued Timing
in The Astrophysical Journal
Andersson N
(2016)
Beyond ideal magnetohydrodynamics: From fibration to 3+1 foliation
Description | The research contributed to discoveries with gravitational-wave astronomy and our understanding of black holes and neutron stars (as detailed in the published work). |
Exploitation Route | Improved understanding of gravity and matter under extreme conditions. |
Sectors | Education |
Description | BEPE-FAPESP fellowship (Brazil) |
Amount | R$ 86,097 (BRL) |
Organisation | São Paulo Research Foundation (FAPESP) |
Sector | Public |
Country | Brazil |
Start | 01/2018 |
End | 01/2019 |
Description | MArie Curie Fellowship |
Amount | € 251,858 (EUR) |
Organisation | European Union |
Sector | Public |
Country | European Union (EU) |
Start | 10/2016 |
End | 09/2019 |
Description | University research fellowship |
Amount | £217,724 (GBP) |
Funding ID | UF160110 |
Organisation | The Royal Society |
Sector | Charity/Non Profit |
Country | United Kingdom |
Start | 10/2017 |
End | 09/2022 |
Description | Gravitational-wave Excellence through Alliance Training (GrEAT) Network with China |
Organisation | University of Glasgow |
Department | Institute for Gravitational Research |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | Consortium of UK gravitational-wave groups to provide training and public outreach in China. Soton co-leads on modelling and data analysis. Funded by SFTC as ST/R002770/1. |
Collaborator Contribution | The project also involves outreach and experimental aspect for both ground- and space-based interferometers. |
Impact | The collaborations is starting 2018 so is still in the set-up phase. |
Start Year | 2018 |
Description | LIGO-Virgo-Kagra Scientific collaboration |
Organisation | California Institute of Technology |
Country | United States |
Sector | Academic/University |
PI Contribution | Prof Ian Jones continues to be a member of the LIGO collaboration, particularly active in the continuous wave search group. |
Collaborator Contribution | The LIGO scientific collaboration is the umbrella organisation for the worldwide search for gravitational waves, the associated data analysis and interpretation of results. |
Impact | The collaboration publishes a large number of high-profile papers each year. |
Description | LIGO-Virgo-Kagra Scientific collaboration |
Organisation | Cardiff University |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | Prof Ian Jones continues to be a member of the LIGO collaboration, particularly active in the continuous wave search group. |
Collaborator Contribution | The LIGO scientific collaboration is the umbrella organisation for the worldwide search for gravitational waves, the associated data analysis and interpretation of results. |
Impact | The collaboration publishes a large number of high-profile papers each year. |
Description | LIGO-Virgo-Kagra Scientific collaboration |
Organisation | Massachusetts Institute of Technology |
Country | United States |
Sector | Academic/University |
PI Contribution | Prof Ian Jones continues to be a member of the LIGO collaboration, particularly active in the continuous wave search group. |
Collaborator Contribution | The LIGO scientific collaboration is the umbrella organisation for the worldwide search for gravitational waves, the associated data analysis and interpretation of results. |
Impact | The collaboration publishes a large number of high-profile papers each year. |
Description | LIGO-Virgo-Kagra Scientific collaboration |
Organisation | University of Birmingham |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | Prof Ian Jones continues to be a member of the LIGO collaboration, particularly active in the continuous wave search group. |
Collaborator Contribution | The LIGO scientific collaboration is the umbrella organisation for the worldwide search for gravitational waves, the associated data analysis and interpretation of results. |
Impact | The collaboration publishes a large number of high-profile papers each year. |
Description | LIGO-Virgo-Kagra Scientific collaboration |
Organisation | University of Birmingham |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | Prof Ian Jones continues to be a member of the LIGO collaboration, particularly active in the continuous wave search group. |
Collaborator Contribution | The LIGO scientific collaboration is the umbrella organisation for the worldwide search for gravitational waves, the associated data analysis and interpretation of results. |
Impact | The collaboration publishes a large number of high-profile papers each year. |
Description | LISA Consortium |
Organisation | Max Planck Society |
Department | Max Planck Institute for Gravitational Physics |
Country | Germany |
Sector | Academic/University |
PI Contribution | Prof Leor Barack plays a leading role on the modelling of gravitational waves for the space based interferometer LISA and leads one of the working groups for the International Science Team. |
Collaborator Contribution | Developing the technology for a space based gravitational wave instrument, alongside data analysis algorithms and theory modelling. |
Impact | Successful LISA Pathfinder mission. |
Description | Newton STFC Capacity Building with LIGO-India |
Organisation | Indian Initiative in Gravitational-wave Observations |
Country | India |
Sector | Charity/Non Profit |
PI Contribution | Southampton are lead on modelling and outreach efforts in a collaboration between a consortium of UK gravitational wave groups and LIGO India. |
Collaborator Contribution | In the initial phase, provided a range of outreach material and contributed to the formation of the collaboration. |
Impact | Still at the set-up stage. |
Start Year | 2018 |
Description | Newton STFC Capacity Building with LIGO-India |
Organisation | University of Glasgow |
Department | Institute for Gravitational Research |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | Southampton are lead on modelling and outreach efforts in a collaboration between a consortium of UK gravitational wave groups and LIGO India. |
Collaborator Contribution | In the initial phase, provided a range of outreach material and contributed to the formation of the collaboration. |
Impact | Still at the set-up stage. |
Start Year | 2018 |
Description | Einstein talk |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Schools |
Results and Impact | Talk on Einstein and gravity In Bangalore, India, organised by ICTS in Bangalore |
Year(s) Of Engagement Activity | 2017 |
Description | Royal Society Summer exhibit |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Public/other audiences |
Results and Impact | Gravitational wave exhibit at Royal Society Summer Exhibit 2017 and special event at Science Museum, London. |
Year(s) Of Engagement Activity | 2017 |
Description | Science comedy |
Form Of Engagement Activity | A broadcast e.g. TV/radio/film/podcast (other than news/press) |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Public/other audiences |
Results and Impact | Prof Andersson participated in Radio 4 Infinity Monkey Cage episode on gravitational waves. |
Year(s) Of Engagement Activity | 2018 |