How long have I been a postdoc? It’s a little difficult to quantify.

I finished my PhD thesis in December 2020, and submitted it in January 2021. I passed my viva in February 2021. I spent a few months climbing the walls waiting for my Spanish visa, and trying to do research at the same time. I signed my contract and officially started my job at the IFT in June 2021. I took nearly a month of holiday starting in mid-July 2021. And here we are in October and I feel like I’m only just finding my postdoctoral feet.

My transition from PhD student to postdoc has been difficult and emotionally draining. I imagine it’s similar for many people, especially with all the restrictions of Covid. It’s very hard to move to a new country (or even just a new city) and build a new social network while everyone is working from home, like cloistered monks scrivening away in their own private cells.

Accordingly, while 2020 was for me something of an annus mirabilis in terms of research, 2021 has been decidedly the opposite. I finally finished a paper that has been in the works since summer 2020, on a new flavour of interacting dark energy which we called the Shan–Chen interacting vacuum. You can find it on arXiv here: arxiv.org/abs/2109.08676 (soon to appear in MNRAS).

I also started two projects directly concerned with my postdoc, and one which is separate. The first project is building tangentially on my paper from last year where we studied the ability of standard sirens to constrain deviations from the distance duality relation. We’re investigating if a future gravitational wave detector such as the Einstein Telescope will be able to detect primordial black hole mergers and distinguish them from astrophysical ones. I say we — my involvement in this project has been steadily diminishing as time has gone on. Some of the crucial work for the project took place between June and September, and I was very much detached from work then. I was struggling with my mental health* in a way which I haven’t for many years, clearly a direct result of the stress of the past eighteen months or so, as well as a double whammy of culture shock and homesickness.

Anyway, the result of this is that my contribution to this project has been minimal. I desperately want to do something but so far I have not been able to identify a particular task which will be of any use.

I’m having more success (and accordingly, enjoying a lot more) my second project. This is on a totally new topic (to me): strong gravitational lensing. I spent a good couple of months before the summer studying the theoretical background, and now I’m having a lot of fun implementing a new strong lensing formalism in the public code lenstronomy. I’m starting to realise that one of my strengths in research is messing about with other peoples’ code. I don’t know how useful that will be down the line, but it’s served me well enough so far. I was also pleasantly surprised at how quickly I began to understand the theory of strong lensing, and especially how quickly I was able to learn and modify the code.

Finally, the third project I’m working on is something a little more relaxed and a little more low scale. We’re investigating the degeneracy between the H0 tension and violations of the distance duality relation, and we may end up using some gravitational wave mock data for that too.

Apart from these different projects, I’m making an effort to contribute regularly to the cosmology journal club at the IFT, something which I find is getting easier and less stressful the more I do it (who’d’ve thought…). I’ve given a couple of Zoom seminars recently, one at Leiden and one at Nottingham. I want to shop myself around a bit more in the coming months, especially at UK departments, considering that I will be on the job market again next year.

So what have I learnt in the first N months of my postdoc? That I am fairly comfortable with working on two projects at once; three becomes difficult if I need to make big contributions to all of them; and four is extremely stressful. That I need to remember that I have a PhD and actually do know stuff (and can learn new stuff quite easily), as this is a quick and easy confidence boost. That it takes on the order of two months to settle into a new place and get into a routine.

And what do I want to learn? Primarily how to become more self-directed in research. I have a really hard time knowing what to do next in a project. For some people, the next step to take or the next idea to try or the next thing to test seem incredibly obvious, while to me they are almost invariably opaque. I’m not sure if there is anything I can actively do to improve this, or whether it will just come with time and experience (neither of which I have much of before the next round of applications).

But for now, I’m taking it one day at a time.

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* When I committed to updating this blog more regularly in January 2020, I made a conscious decision not to talk too much about my own personal feelings and in particular my own mental health. However, it does no one any good to brush this topic under the carpet. My mental health over the period June — September 2021 was at its lowest ebb in about five years. I’m trying to be kind to myself when judging the impact this has had on my work. Now that I’m more settled in my job and life, things are improving. I am hopeful that my next move, to Paris in three months, does not result in such a big disruption.