I’d wanted to be a physicist ever since I was a kid. Of course, back then I had no real idea what exactly a physicist did. What I did know from books was that the sun was very big, but that there were many stars in our galaxy so much bigger; that all the wildly different things in our world were made from just a few varieties of inconceivably tiny atoms, but that those were made of tinier things still; that time did not just go back further than the building of the pyramids, but further than the birth of my species, my star, my galaxy. To a mildly obsessive youngster, it seemed that learning about these things would be a very fine thing indeed.

Physicists come to the field in all kinds of different ways, but some version of this wonderment is shared by all of us. It is what compels us to go through a decade of formal university education. The original research you do during your PhD prepares you, to some extent, for what’s expected in the next three to 10 years as a postdoctoral researcher at various institutions. These appointments are for a few years at a time, don’t pay a lot, and are exceedingly hard to get. You have to prove your capacity as an independent researcher, basically putting work ahead of everything else. I am a postdoc, and I’m trying to keep my eye on the prize, which only a tiny minority attain: a tenure-track position as a professor. Only once you land one of those do you have a good shot at actually doing this physics thing for the rest of your career.

As a high-energy theorist, I try to think about the most fundamental laws of nature that we could understand. This involves phenomena smaller than an atomic nucleus, which can be experimentally probed by smashing protons or electrons together in huge facilities such as the Large Hadron Collider in Switzerland. Since the universe started out much smaller than this, our theories also touch upon the study of the big bang, traces of which can be discerned using powerful telescopes. Some of the most exciting work has to do with theories or physical scenarios that will be out of experimental reach for a long time, maybe for ever.

In practical terms, there are parts of my job that are roughly in line with my childhood expectations. We think about theories that have been proposed to describe some aspect of the subatomic world, such as dark matter or the Higgs boson, and occasionally come up with new ones. We calculate their predictions, hoping they can be tested soon. This is usually in collaborations of two to five people.

The actual work is done partially on pen and paper, especially to formally understand a mathematical model or physical mechanism. For detailed computations, we often write programs and run them on laptops or supercomputers. There are lots of meetings and Skype calls with collaborators to feel our way forward, and once we figure out something worthwhile, we write a paper together, usually a few per year per person, but this varies significantly.

Other parts of the job have turned out to be a bit more surprising. It’s unbelievably social: we’re all about getting together and chatting in front of a blackboard, around an espresso machine, or during a strenuous hike, where many new ideas are born. This is one of the unexpected pleasures of being a theorist, but it also comes with a gruelling amount of travel to give seminars and attend conferences. Dozens of work trips per year are not unusual and wear you down. Since we spend a lot of time presenting our research to one another, a degree of oratory skill and charisma can play no small role in one’s success. Some see this as a burden; others, including me, enjoy the chance to put on a good show.

It’s a very rich professional experience, but there are significant downsides, and if this wasn’t your dream job, you might absolutely hate it. The work is entirely open-ended and self-motivated. This is a delicious freedom most of us couldn’t do without, but also a source of insecurity we never stop struggling with (look up “imposter syndrome”). The working hours are long and sometimes lonely. Having to move to a new position every few years until you hope to land a faculty job is not exactly a recipe for stability, and it’s asking a lot from your partner or spouse. I’m lucky that my partner puts up with all this, but it doesn’t always work out. The large majority leave academia at one stage or another, usually when they can’t find another job (budgets are shrinking) or the personal cost becomes too high. They typically end up reinventing themselves in finance, analytics or software-related industries. Unlike a chemist or even other kinds of physicists, a high-energy theorist moving into the private sector usually has no choice but to leave their passion behind.

All of this takes its toll. The decade or so spent in low-paying jobs and moving from place to place, the importance of academic pedigree and personal recommendations for getting ahead, and the ultimately very low chance of landing a permanent position, all contribute to a deplorable lack of women and ethnic minorities in the field. This is apart from the usual overt or covert biases that make it difficult to break into the old boys’ club. I sincerely hope that we can overcome these institutional barriers and make it more welcoming to everyone, because I couldn’t be happier doing what I do, and everyone with the talent and passion deserves a fair shot at doing the same thing. This field and its rarefied pool of individuals rapidly disabuses you of any ill-conceived notion that the intellectual gifts that propelled you through school and university are anything of real significance. It’s a humbling perspective for anyone who fancies themselves a bit of a smarty-pants.

At its best, the job allows us to experience moments of sublime joy: every now and then, you feel like you are uncovering nuggets of universal, objective truth about the cosmos. These moments of transcendence are predicated by months and years of confusion, obsession, mistakes and incremental work. Even if a particular discovery or insight isn’t your own, being able to understand it and grasp its significance inspires awe. Almost all of us are atheists, but we worship at the altar of nature.

I know our work is important in its own right, but like most of us, I selfishly do what I do because I can’t imagine doing anything else. Given all of its flaws, it is incredible that society recognises the value of basic research, and lends its support. We serve at its pleasure and owe it our gratitude.

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