"Doing research is a bit like solving a jigsaw puzzle", says Victor Lagerkvist. He received his PhD in theoretical computer science in 2016. After a two-year research stint in Germany, he returned to Linköping University to work at the Department of Computer and Information Science (IDA).
Please tell us about your research.
My research area is theoretical computer science, which can be understood as a type of mathematics. I work with theoretical models of computers. For example, I study the complexity of problems – that is, I’m trying to understand the number of steps required to solve a problem. I conduct basic research, which means that my research is theoretical. At some later point you might find practical applications for my results – often, the applications have to do with optimisation, making computers calculate more efficiently
But when I do research, I don't think about that. What is interesting to me are the theoretical aspects.
Tell us a bit about your background.
I did the bachelor's programme in computer science here at Linköping University. After that, I continued to do a master's in computer science. I did my degree project here at the Department of Computer and Information Science.
Why did you decide to become a PhD?
Computer science consists of many different subjects: cognitive psychology, artificial intelligence, programming, theoretical computer science and so on. When I started to take theoretical courses, I found them fascinating, and I wanted to learn more. When I chose the topic for my degree project, I made sure it would be suitable for a PhD.
What's most exciting about conducting research?
It's exciting when I manage to prove that something is true. To do research is a bit like solving a jigsaw puzzle. You have certain definitions, and in the end, it must all work out. Sometimes you won't manage to find a solution, and you'll have to go back to the drawing table. But sometimes everything falls into place – surprisingly often, actually.
Please describe a typical day for you as a PhD student.
When I do research, I don't use computers, I use pen and paper to conduct proofs. When I was a PhD student, I tried to work from home until lunch if it was possible. I live in Norrköping, and the Department of Computer and Information Science is located in Linköping. I preferred to take a later bus. How my days were structured depended on my teaching assignment and which courses I took. For your teaching and the mandatory courses, you need to be at the university, but apart from that I had no obligations. You don't clock in and out, but you are responsible for your own work. It's essential to learn to manage this freedom. You need to set goals, and you need to learn how to work, without making much progress. It can be frustrating. You work hard for several weeks, in the worst case for months, without much happening, but then, suddenly, things fall into place.
If you are a student and want to do a PhD, how do you go about it?
One way is through your degree project. Make it clear to your supervisor from the start that you intend to do a PhD. After I finished my degree project, the Department of Computer and Information Science hired me as a research assistant. When the lab where I was working advertised a PhD position, I applied. These advertisements are public, so it's not certain that you will get the job, but it’s likely that there's a good chance.
What should you consider when you choose a university for your PhD?
The university itself is not that important; it's more about the research group. That is what you should examine. A less well-known university might have excellent research groups.
You mentioned that conferences are important.
Yes, you present your research at conferences. They are of great importance in computer science in general, not only in theoretical computer science. For mathematical research scientific journals are more important. The conferences are international and are a place where researchers from all over the world gather. It's an excellent place to meet like-minded people.
What qualities are good to have when you want to do a PhD?
Curiosity and the ability to gather information from different sources and evaluate it in a critical manner. Independence is also essential.
What is most challenging about doing a PhD?
Sometimes you'll get stuck, and that is annoying.
If you could give one piece of advice to yourself before you started your PhD, what would that be?
Don't worry too much. You will get results.
You are now working at Linköping University. Why did you choose to do that?
I wanted to continue in academia. After I'd gotten my PhD, I went, like many others, on a postdoc. I did research for two years in Dresden. It was inspiring. Since 2018 I have been back at the Department of Computer and Information Science. I am a research fellow. The reason I chose to do my PhD and now work here at IDA is that I like it. Our research group is strong, and I have great colleagues. One crucial difference from being a PhD student is that I'm now in charge of examinations for the courses that I teach, but my job still constitutes a lot of research. The next big step for me is to receive my lectureship. I'm waiting for that now. Then I can start to supervise my own students, who will work on my research project. I want to continue to work at the university. I like the environment – there's flexibility, and you are responsible for your projects. You can work at your own pace. It suits me.
