Realistic profile evaluation for physics PhD

[Alpha_orionis]

Hi everyone!

Now that my first two applications have been submitted and the wait has begun, I have been having massive impostor syndrome and wracking my nerves about my chances of getting a place and funding. My research interests lie in computational and theoretical aspects of cosmology, mainly related to early-universe physics and modified gravity. I am aware that applying to Oxbridge is a bit of a crapshoot, but I found amazing prospective supervisors and thesis topics there, so I guess it is worth a try... My main fear is that the admission officers won't understand the Swiss grading system: in my country, the main goal is to pass, it is frequent for people to barely get 4/6, and any grade above 5 is considered very good. But compared to students from USA or Canada who arrive with straight As and perfect GPAs, I am afraid my 5.42/6 average won't look impressive... Also, despite having some publications, none of them are both peer-reviewed and directly in my field. Can anyone estimate my chances, so that I know what to expect and don't get too crushed in case of multiple rejections?

Applying to: Cambridge Physics PhD, Oxford Astrophysics DPhil, Manchester Theoretical Physics PhD, McMaster/Perimeter Institute Physics PhD

Previous Institutions: Bsc + Msc at EPFL (Switzerland), exchange year at UBC Vancouver (Canada)

Major: Physics

Years out of school: 0, will finish my master in July 2021

GPA: 5.42/6 at EPFL, 4.24/4.3 during exchange year

GRE: not required, not taken

Relevant Background: Honours thesis in radioastronomy (published online, but not in a peer-reviewed journal), semester projects about gravitational lensing and dark energy (might result in a publication, but waiting for additional data from another group), master project about machine learning applied to gravitational cosmology (in progress). Relevant coursework in general relativity, observational and theoretical cosmology, computational physics, quantum physics. Currently taking PhD-level courses in advanced quantum field theory, gauge theories,  conformal field theory and gravity.

Relevant Work Experience: 3 teaching assistantships, volunteer work as a coach and juror in a Swiss science competition

Other experience: 2 gold and 2 bronze medals after 4 participations in an international physics competition, top 10 placement in a Canadian national physics exam, poster presentation in the Swiss finals of a young researchers contest. 5 outreach conferences, 1 first-author publication in social sciences (related to a project about space debris cleaning), another publication in a Swiss science education journal (related to my volunteer work).

Languages: French (native), English (IELTS 8.5), intermediate German

LOR: unknown strength (haven't seen them), from project supervisors in the 3 labs I have done research with