PhD Applications
PhD Applications
We welcome applications to join the Particle Cosmology Group as a postgraduate student and carry out research for a PhD degree. Details of the Groups' interests can be found in our research and people pages.
All PhD applications must be made centrally, through the Researcher Academy. The deadline for PhD applications is 24th January 2025. You can find further details on how to apply here. Please state your interest in the Particle Cosmology group on your application. Once you have submitted your application, please also send a brief email containing your application ID to the particle cosmology admissions coordinator, David Stefanyszyn.
We particularly welcome applications for PhDs funded by the Bell Burnell Scholarship (beta.iop.org/bellburnellfund) from applicants who are elegible for home/UK fees and belong to a currently under-represented group in Physics. For example students who are female, from a black, asian, or minority ethnic background, or who have experienced other hurdles to their success as a physicist. The deadline for applications for this Scholarship scheme is the 15th of November 2024. Please contact David Stefanyszyn for more details or to express your interest.
Potential supervisors for a PhD are listed on the academic staff page for the Particle Cosmology group. Below are some examples of potential PhD projects to begin in September/October 2025. However, other projects will also be available and can be discussed with applicants. If the projects listed below do not align with your research interests, we still encourage you to apply and ask you to clearly state in your application what your interests are.
The infinity puzzle: from number theory to quantum gravity
In quantum field theory, theoretical physicists have developed a magnificent tool for describing the microscopic world of fundamental fields, its predictions tested to an accuracy of one part in a trillion. But behind this triumph is a dirty secret – the manipulation of infinities. This is manifested in the method of “regularisation” and “renormalisation” which Feynman famously described as “sweeping the infinities under the rug.” This project will look “under the rug” by systematically studying connections between regularisation methods in number theory, quantum field theory, and string theory, the latter providing a window into how Nature might protect us from infinity. This PhD studentship is led by
Antonio Padilla.
Dark energy in fundamental theory
Cosmological observations indicate that the universe is going through a phase of accelerated expansion, driven by a substance dubbed dark energy, whose microscopic energy remains unknown. Deriving a consistent theory of dark energy from fundamental theory, specifically string theory, is an ongoing challenge. This project will seek to develop various ways to achieve that and to better understand the obstacles. Further, it is well known that the scale of dark energy is very low compared to other scales in fundamental physics. This leads to problems of naturalness, and in particular the cosmological constant. This project will also seek to develop a better understanding of, and solutions to, the cosmological constant problem. This PhD studentship is led by
Antonio Padilla.
Cosmic bubble growth in quantum field theory
In the early Universe there is the possibility of phase transitions, with bubbles nucleating and expanding to complete the transition. In the context of gravitational waves, one of the important quantities that determines the strength of the signal is the bubble wall speed, which is affected by interactions with the particles that the bubble sweeps up. In this project we will use techniques from numerical quantum field theory to simulate the bubble's expansion, and so give a direct computation of the wall speed. This PhD studentship is led by
Paul Saffin and
Oliver Gould.
Seeded quantum tunnelling
Tunnelling processes play an important role in many areas of physics, with tunnelling from a homogeneous state being well-studied in relativistic field theories. A key example is the tunnelling of the Higgs field from a metastable to a stable minimum in the early universe. In experimental setups, however, one typically finds that tunnelling is triggered by seeds. Such seeded-tunnelling is less well-developed in realvistic field theory, so this project will seek to compute the effect of soliton seeds on the nucleation rate and dynamics of a tunnelling field. This PhD studentship is led by
Paul Saffin and
Oliver Gould.
Further information on the admissions procedure can be found here. All applications should be made online here where the prospectus can also be found. Once you have submitted your application, please also send a brief email containing your application ID to the particle cosmology admissions coordinator, David Stefanyszyn.