Jan Vondruška from the Czech Republic looks back on a month filled with new insights, inspiring encounters, and fresh perspectives on his research.

During his stay, we quickly got to know Jan as an open, friendly, and highly motivated young scientist who became an active part of our department almost immediately. It felt as though he had always been part of the team. In the following, he shares his experience and offers a glimpse into what it is like to join the Department of Mathematics at the University of Salzburg as a visiting researcher.

Jan is currently pursuing his PhD in number theory at Masaryk University in Brno. His research field closely aligns with the expertise of Professor Volker Ziegler, which made Salzburg a natural destination for an academic exchange.

“The reason that I chose mathematics for my PhD was simple – out of potential available careers, I felt that research in mathematics was the possibility I was most passionate about. My research over the course of my PhD has focused mainly on finding new units in certain number fields, and the consequences of finding these units on annihilation of the class groups of these fields; however, over the course of my stay in Salzburg, I found that I could branch out and focus my research on other number theoretical problems.”

The connection between Jan and Professor Ziegler was first established at the Central European Number Theory Conference held in Salzburg in September 2025. What began as an academic exchange soon developed into an invitation for a research stay.

“I really enjoyed my time here and the community seemed to be very inviting, and so I felt like it would be natural to ask if I could arrange a stay.”

Jan has always been curious about experiencing new environments and building international connections. He highlights how valuable these exchanges can be, both personally and professionally. In Salzburg, he particularly appreciated the collegial atmosphere and the daily interactions at the department—something quite different from his usual routine in Brno, where he often works remotely.

While his experience was overwhelmingly positive, there were also small challenges. Adjusting to a new daily rhythm and making the most of his evenings sometimes proved difficult. In addition, he noted that the cost of living in Salzburg is somewhat higher than in Brno, which could become a factor during a longer stay. Still, the advantages clearly outweighed the drawbacks: having his own apartment and being able to walk to most places added greatly to his quality of life.

“There are two aspects of my stay that I enjoyed a lot, and I would give them equal importance – one is meeting the people in the mathematics department and spending time with them (whether we talk about mathematics or completely unrelated topics), and the other aspect is the activities one can engage in when staying in Salzburg – whether it’s hiking, skiing, or just walking around downtown, there are many things one can experience in a new location, especially one as nice as Salzburg.”

Looking ahead, Jan is considering gaining experience in the private sector before completing his doctoral studies. This would not only provide financial stability but also help him decide whether his long-term path lies in academia or industry.

For students thinking about spending time abroad, he offers clear and practical advice:

“If able, do it. You can spend some time abroad, meet new people doing work you’re interested in, and just see what life is like outside of what you’re used to.”

Jan’s visit was a valuable addition to our department—both academically and personally. We sincerely hope to welcome him back to Salzburg in the future and look forward to the experiences and stories he will bring with him next time.