The Universe in Light of Fundamental Physics
Lead Research Organisation:
King's College London
Department Name: Physics
Abstract
Particle physics and cosmology are merging. In recent years, the cross-pollination of ideas between the fields has accelerated, fueled by the availability of a wealth of new raw astrophysical data and increased realization of the intimate theoretical connection between particle physics and cosmology. Now that the LHC is online, particle physics is returning the favour with high-quality data on the building-blocks of cosmology. With the coming release of data from the PLANCK satellite and many balloon experiments, the Advanced LIGO gravitational-wave detectors, the AMS-02 space-based particle detector, the Dark Energy Survey (DES), and many other experiments searching for dark matter, this cross-pollination of ideas and data is destined to continue.
The scientific programme proposed here by the Theoretical Particle Physics and Cosmology (TPPC) Group in the Physics Department of King's College London is focused on the the analysis and interpretation of data from observational cosmology and high-energy astrophysics using insights from fundamental physics.
Although the LHC now makes possible direct studies in the laboratory of fundamental physics processes at unprecedented energies, these are eclipsed by the energies attained in the Very Early Universe and in the ultra-high-energy cosmic rays that may be produced by Active Galactic Nuclei (AGNs), gamma-ray bursters (GRBs), supernovae, black holes and pulsars. The cosmic microwave background (CMB) and violent astrophysical events therefore provide unique laboratories for studying new fundamental physics. However, while searching for observational signatures of new physics, one must model known physics accurately, taking into account the information provided by the LHC and other accelerators. For example, the wealth of new data on the CMB and large-scale structure (LSS) necessitates the development of new analysis tools to probe and interpret possible signatures of new physics such as primordial non-Gaussianities and small neutrino masses, so as to distinguish them from more conventional phenomena. Likewise, searches for dark matter require accurate modelling of dark matter halos in order to calculate reliably density and velocity distributions as well as to probe for deviations from the usual weakly-interacting dark matter paradigm, such as self-interactions. Moreover, high-energy emissions from astrophysical sources provide unique opportunities to search for new physics that complement particle colliders and could yield striking observational signatures.
The scientific programme proposed here by the Theoretical Particle Physics and Cosmology (TPPC) Group in the Physics Department of King's College London is focused on the the analysis and interpretation of data from observational cosmology and high-energy astrophysics using insights from fundamental physics.
Although the LHC now makes possible direct studies in the laboratory of fundamental physics processes at unprecedented energies, these are eclipsed by the energies attained in the Very Early Universe and in the ultra-high-energy cosmic rays that may be produced by Active Galactic Nuclei (AGNs), gamma-ray bursters (GRBs), supernovae, black holes and pulsars. The cosmic microwave background (CMB) and violent astrophysical events therefore provide unique laboratories for studying new fundamental physics. However, while searching for observational signatures of new physics, one must model known physics accurately, taking into account the information provided by the LHC and other accelerators. For example, the wealth of new data on the CMB and large-scale structure (LSS) necessitates the development of new analysis tools to probe and interpret possible signatures of new physics such as primordial non-Gaussianities and small neutrino masses, so as to distinguish them from more conventional phenomena. Likewise, searches for dark matter require accurate modelling of dark matter halos in order to calculate reliably density and velocity distributions as well as to probe for deviations from the usual weakly-interacting dark matter paradigm, such as self-interactions. Moreover, high-energy emissions from astrophysical sources provide unique opportunities to search for new physics that complement particle colliders and could yield striking observational signatures.
Planned Impact
These projects will enable the King's Theoretical Particle Physics and Cosmology Group to have significant global impact at the interfaces between early-Universe cosmology, high-energy astrophysics and fundamental physics.
1) Predictions and Observations of Non-Linear Physics in the Early Universe: We will develop new methodologies and observables to probe the Early Universe, enlarging the theoretical and observational window into theories of the Early Universe. We will build a full general relativistic numerical code with adaptive mesh refinement that is applicable to cosmological problems -- a code we intend to make publicly available. We will test and confirm (or disprove) several conjectures of strong gravity physics in cosmology such as the formation of black holes in cosmological collisions, and the stability of Black Rings.
2) Astrophysical Modelling of Dark Matter: We will obtain a greater understanding of the distribution of dark matter in galaxies. We will create new methods of analysing data based on higher moments of the Jeans equation, enabling us to constrain further the dark matter parameter space and provide an additional astrophysical window into the nature of dark matter, be it cold, warm, self-annihilating or
self-interacting. We will measure the expansion history of the Universe with high-energy gamma rays and place independent constraints upon the equation of state of dark energy (or equivalently the nature of modified gravity). We will test fundamental physics by looking for the observational effects of axion-like dark matter candidates.
3) Signatures of Fundamental Symmetries in Astrophysics: We will obtain new and better contraints on the amplitude and type of Lorentz Symmetry violations. We will obtain the strongest possible astrophysical constraints on the principle of equivalence with time-varying sources of high-energy particles. We will develop new modeling techniques of energy astrophysical sources, and test fundamental symmetries using data from Fermi, HESS II and CTA.
These projects will have significant impact on several academic communities: observers seeking to characterize phenomena in the early Universe, astrophysicists seeking to characterize dark matter, general relativists seeking a new generation of numerical tools, and particle physicists developing theories beyond the Standard Model.
1) Predictions and Observations of Non-Linear Physics in the Early Universe: We will develop new methodologies and observables to probe the Early Universe, enlarging the theoretical and observational window into theories of the Early Universe. We will build a full general relativistic numerical code with adaptive mesh refinement that is applicable to cosmological problems -- a code we intend to make publicly available. We will test and confirm (or disprove) several conjectures of strong gravity physics in cosmology such as the formation of black holes in cosmological collisions, and the stability of Black Rings.
2) Astrophysical Modelling of Dark Matter: We will obtain a greater understanding of the distribution of dark matter in galaxies. We will create new methods of analysing data based on higher moments of the Jeans equation, enabling us to constrain further the dark matter parameter space and provide an additional astrophysical window into the nature of dark matter, be it cold, warm, self-annihilating or
self-interacting. We will measure the expansion history of the Universe with high-energy gamma rays and place independent constraints upon the equation of state of dark energy (or equivalently the nature of modified gravity). We will test fundamental physics by looking for the observational effects of axion-like dark matter candidates.
3) Signatures of Fundamental Symmetries in Astrophysics: We will obtain new and better contraints on the amplitude and type of Lorentz Symmetry violations. We will obtain the strongest possible astrophysical constraints on the principle of equivalence with time-varying sources of high-energy particles. We will develop new modeling techniques of energy astrophysical sources, and test fundamental symmetries using data from Fermi, HESS II and CTA.
These projects will have significant impact on several academic communities: observers seeking to characterize phenomena in the early Universe, astrophysicists seeking to characterize dark matter, general relativists seeking a new generation of numerical tools, and particle physicists developing theories beyond the Standard Model.
Organisations
- King's College London (Lead Research Organisation)
- UNIVERSITY OF OXFORD (Collaboration)
- QUEEN MARY UNIVERSITY OF LONDON (Collaboration)
- STFC DiRAC COSMOS Shared Memory Service (HPC Facility Cambridge) (Collaboration)
- Argonne National Laboratory (Collaboration)
- UNIVERSITY OF CAMBRIDGE (Collaboration)
- Intel (United States) (Collaboration)
People |
ORCID iD |
Eugene Lim (Principal Investigator) |
Publications
Blas D
(2015)
Phenomenology of theories of gravity without Lorentz invariance: The preferred frame case
in International Journal of Modern Physics D
Clough K
(2015)
GRChombo : Numerical relativity with adaptive mesh refinement
in Classical and Quantum Gravity
Clough K
(2017)
Robustness of inflation to inhomogeneous initial conditions
in Journal of Cosmology and Astroparticle Physics
Clough K
(2016)
Robustness of Inflation to Inhomogeneous Initial Conditions
Clough K
(2018)
Robustness of inflation to large tensor perturbations
in Journal of Cosmology and Astroparticle Physics
Clough K
(2017)
Robustness of Inflation to Large Tensor Perturbations
Denton-Turner O
(2022)
Weak lensing "post-Born" effects are equivalent to pure lens-lens couplings
in Journal of Cosmology and Astroparticle Physics
Denton-Turner O
(2021)
Weak lensing "post-Born" effects are equivalent to pure lens-lens couplings
Helfer T
(2017)
Black hole formation from axion stars
in Journal of Cosmology and Astroparticle Physics
Helfer T
(2016)
Black hole formation from axion stars
Lim E
(2015)
Quantum information of cosmological correlations
in Physical Review D
Su S
(2014)
Formulating weak lensing from the Boltzmann equation and application to lens-lens couplings
in Physical Review D
Description | We have released GRCHOMBO to the public domain through the BSD-3 License. This is one of the goals of the grant. |
Exploitation Route | GRCHOMBO has been chosen by DIRAC as one of the "benchmark" code for the procuring of DIRAC-3 resources. It has now being used by other research groups to publish more than 60 research papers. |
Sectors | Other |
URL | http://www.grchombo.org |
Description | FQXi Large Grant Round 2016 |
Amount | $121,462 (USD) |
Organisation | Foundational Questions Institute (FQXi) |
Sector | Charity/Non Profit |
Country | United States |
Start |
Description | COSMOS Consortium |
Organisation | STFC DiRAC COSMOS Shared Memory Service (HPC Facility Cambridge) |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | I am board member of the COSMOS consortium. In addition to HPC concerns, we are also collaborating on the public release and development of the numerical code GRCHOMBO of which I am a primary developer and founder. |
Collaborator Contribution | Provide computing resources. Technical and development work on GRCHOMBO. |
Impact | Several scientific papers written with the use of the facility, and with technical assistance from the consortium members. Organized a conference on numerical cosmology. Technical and development work on GRCHOMBO. |
Start Year | 2010 |
Description | GRCHOMBO Code Collaboration |
Organisation | Argonne National Laboratory |
Country | United States |
Sector | Public |
PI Contribution | I am one of the three co-founders of the GRCHOMBO code collaboration. The code is a state of the art numerical relativity code that is publicly available. My research group is very active in maintaining and contributing to the code. |
Collaborator Contribution | They contribute to the development of the code. |
Impact | GRCHOMBO, a multi-purpose numerical relativity code, is now open sourced and available. |
Start Year | 2011 |
Description | GRCHOMBO Code Collaboration |
Organisation | Intel Corporation |
Country | United States |
Sector | Private |
PI Contribution | I am one of the three co-founders of the GRCHOMBO code collaboration. The code is a state of the art numerical relativity code that is publicly available. My research group is very active in maintaining and contributing to the code. |
Collaborator Contribution | They contribute to the development of the code. |
Impact | GRCHOMBO, a multi-purpose numerical relativity code, is now open sourced and available. |
Start Year | 2011 |
Description | GRCHOMBO Code Collaboration |
Organisation | Queen Mary University of London |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | I am one of the three co-founders of the GRCHOMBO code collaboration. The code is a state of the art numerical relativity code that is publicly available. My research group is very active in maintaining and contributing to the code. |
Collaborator Contribution | They contribute to the development of the code. |
Impact | GRCHOMBO, a multi-purpose numerical relativity code, is now open sourced and available. |
Start Year | 2011 |
Description | GRCHOMBO Code Collaboration |
Organisation | University of Cambridge |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | I am one of the three co-founders of the GRCHOMBO code collaboration. The code is a state of the art numerical relativity code that is publicly available. My research group is very active in maintaining and contributing to the code. |
Collaborator Contribution | They contribute to the development of the code. |
Impact | GRCHOMBO, a multi-purpose numerical relativity code, is now open sourced and available. |
Start Year | 2011 |
Description | GRCHOMBO Code Collaboration |
Organisation | University of Oxford |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | I am one of the three co-founders of the GRCHOMBO code collaboration. The code is a state of the art numerical relativity code that is publicly available. My research group is very active in maintaining and contributing to the code. |
Collaborator Contribution | They contribute to the development of the code. |
Impact | GRCHOMBO, a multi-purpose numerical relativity code, is now open sourced and available. |
Start Year | 2011 |
Title | GRChombo Numerical Relativity Code |
Description | Full Adaptive Mesh Refinement capable Numerical Relativity code. |
Type Of Technology | Software |
Year Produced | 2018 |
Open Source License? | Yes |
Impact | Code is now in production phase with science output forthcoming by the beginning of 2015. Code is released under BSD-3 License in 2018. |
URL | http://www.grchombo.org |
Description | Article for New Scientist |
Form Of Engagement Activity | A magazine, newsletter or online publication |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Media (as a channel to the public) |
Results and Impact | Wrote an article on general relativity and quantum mechanics for the popular science magazine New Scientist. |
Year(s) Of Engagement Activity | 2015 |
Description | Interviewed by BBC4 as part of Science Program |
Form Of Engagement Activity | A press release, press conference or response to a media enquiry/interview |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Media (as a channel to the public) |
Results and Impact | I was filmed by BBC4 as part of a science special hosted by Prof Jim Al-Khalili. |
Year(s) Of Engagement Activity | 2016 |
Description | Interviewed by ITV. |
Form Of Engagement Activity | A press release, press conference or response to a media enquiry/interview |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Public/other audiences |
Results and Impact | Interviewed by ITV for 6 o'clock news for Big Ben clock "anomaly". |
Year(s) Of Engagement Activity | 2015 |
Description | Interviewed on Radio by US based National Public Radio |
Form Of Engagement Activity | A press release, press conference or response to a media enquiry/interview |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Media (as a channel to the public) |
Results and Impact | I was interviewed on live radio (US National Public Radio) on the Colin McEnroe show. |
Year(s) Of Engagement Activity | 2016 |
URL | http://wnpr.org/post/multiplicity-multiverse |
Description | Public Talk |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Public/other audiences |
Results and Impact | Public talk in a New Scientist event. |
Year(s) Of Engagement Activity | 2016 |
Description | Public Talk at British Library |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Regional |
Primary Audience | Public/other audiences |
Results and Impact | Gave public science talk at British Library |
Year(s) Of Engagement Activity | 2015 |