Non-linear relativistic effects on cosmological perturbations
Lead Research Organisation:
University of Portsmouth
Department Name: Institute of Cosmology and Gravitation
Abstract
The growth of cosmological perturbations is usually studied either through perturbation theory or via non-linear simulations. In the former approach, the full effects of general relativity are included, but the calculations are limited to large scales where the perturbations are small. Conversely, simulations are able to follow the evolution on small scales, but the treatment of gravity is usually approximated as Newtonian. The focus of this project is to understand how a fully relativistic treatment affects the non-linear evolution of structure, and how this will impact our interpretation of the next generation of large scale structure data, such as the Square Kilometre Array (SKA).
The student will be building our recent advances in this area, including a consistent second order relativistic code and our understanding of how Newtonian simulations can be interpreted in a relativistic context. They will also work to determine how line-of sight effects, like gravitational lensing, can impact the observations on the largest scales.
The student will be building our recent advances in this area, including a consistent second order relativistic code and our understanding of how Newtonian simulations can be interpreted in a relativistic context. They will also work to determine how line-of sight effects, like gravitational lensing, can impact the observations on the largest scales.
People |
ORCID iD |
Robert Crittenden (Primary Supervisor) | |
Samuel Lawrence (Student) |
Studentship Projects
Project Reference | Relationship | Related To | Start | End | Student Name |
---|---|---|---|---|---|
ST/N504245/1 | 30/09/2015 | 29/09/2021 | |||
1998600 | Studentship | ST/N504245/1 | 30/09/2017 | 29/09/2021 | Samuel Lawrence |
ST/R505018/1 | 30/09/2017 | 29/09/2021 | |||
1998600 | Studentship | ST/R505018/1 | 30/09/2017 | 29/09/2021 | Samuel Lawrence |
Title | Computer Programming |
Description | In the above box there was not a suitable option. All options listed were related to biological sciences. I have learnt how to program in C and Python over the course of my PhD. |
Type Of Material | Improvements to research infrastructure |
Year Produced | 2017 |
Provided To Others? | No |
Impact | A second-order cosmological Boltzmann code will be developed that can simulate large-scale clustering statistics. The simulated data can then be used to compare the results of the next generation of galaxy redshift surveys. This would not be possible if I could not develop this tool. |
Description | Doctor Christian Fidler |
Organisation | RWTH Aachen University |
Country | Germany |
Sector | Academic/University |
PI Contribution | Together we have started to write parts of a module in a code, SONG, he helped develop. |
Collaborator Contribution | He hosted me over the course of a 4-month research visit to RWTH Aachen. |
Impact | Future paper. |
Start Year | 2019 |
Description | Doctor Obinna Umeh |
Organisation | University of Portsmouth |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | Secondary supervisor. |
Collaborator Contribution | Advised me over the course of my PhD. We meet weekly along with primary supervisor. |
Impact | Future paper. |
Start Year | 2017 |
Description | Professor Robert Crittenden |
Organisation | University of Portsmouth |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | Primary supervisor |
Collaborator Contribution | My supervisor has guided me from the onset of my PhD which commenced October 2017. We have met on a weekly basis. |
Impact | Eventually a paper. |
Start Year | 2017 |
Description | Ask a Scientist |
Form Of Engagement Activity | Engagement focused website, blog or social media channel |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Schools |
Results and Impact | School children and scientists were able to communicate on an instant-messaging platform. Students were able to ask questions about science, careers, education etc. |
Year(s) Of Engagement Activity | 2019 |
Description | Croydon Astronomical Society Talk |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Public/other audiences |
Results and Impact | I gave a talk on simulations in cosmology and how scientists can understand the Universe through this process. |
Year(s) Of Engagement Activity | 2019 |
Description | Meet a Physicist |
Form Of Engagement Activity | Participation in an open day or visit at my research institution |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Schools |
Results and Impact | 60 College students visited the University and we did our best to portray our experiences studying and working within physics. |
Year(s) Of Engagement Activity | 2019 |
Description | Stargazing |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Public/other audiences |
Results and Impact | Local Portsmouth residence were about to visit the dockyard where an event was hosted by our department. The evening consisted of expert panels, workshop activities etc. |
Year(s) Of Engagement Activity | 2018 |