PhD Position in Mathematics with a Focus on Extremal Combinatorics

The Department of Mathematics and Mathematical Statistics at Umeå University is opening a PhD position in mathematics with a focus on extremal combinatorics. The position covers four years of third-cycle studies, including participation in research and third-cycle courses. The last day to apply is January 31st 2026. Project description and tasks: The successful applicant will study problems in extremal and probabilistic combinatorics, as part of Dr. Maryam Sharifzadeh’s project Induced saturation problems for hypergraphs and partially ordered sets (POSets), funded by the Swedish Research Council. This project is concerned with saturation problems for two classes of combinatorial objects: hypergraphs and posets. For hypergraphs, the aim is to better understand weak saturation, a simpler version of the usual notion of saturation, and to improve what we currently know. On the poset side, the project will involve work on both saturation and non-induced saturation, with the goal of making progress on conjectures about the nature of posets that are hardest to saturate. The work will draw on ideas from extremal combinatorics, set theory and probabilistic methods, and it hopes to clarify how these two settings, hypergraphs and posets, connect through their shared saturation questions. Combinatorics and mathematics in Umeå: The successful applicant will be expected to take part in (and contribute to) the life of the Discrete Mathematics group. Discrete mathematics is one of the five main research areas at the Department of Mathematics and Mathematical Statistics, alongside Computational Mathematics, Mathematical Statistics, and Analysis & Modelling. The Discrete Mathematics group consists of 10 faculty members whose research covers a broad range of modern combinatorics. The group runs a weekly seminar and welcomes many visiting researchers throughout the year. Its areas of expertise include extremal combinatorics, discrete probability, combinatorial optimisation, discrete geometry, and computational combinatorics. The main supervisor for this project will be Dr. Maryam Sharifzadeh, and the successful applicant will also have plenty of opportunities to interact with other group members working in extremal and probabilistic combinatorics, including Dr. Victor Falgas-Ravry, Dr. Eero Räty, Professor Klas Markström, and Dr. Istvan Tomon. More information about Discrete Mathematics at Umeå University can be found on the group’s homepage: https://www.umu.se/en/research/groups/discrete-mathematics/ As a PhD student, you will be part of a lively and welcoming group that stays closely connected with the department’s postdoctoral researchers. The community is active both academically and socially, organizing everything from board-game evenings and sports activities to weekly lunches and informal gatherings. Each year, the department also organizes PhD Days, where students spend a couple of days together away from campus to share their experiences, discuss their research, and get to know one another in a relaxed setting. It is a supportive environment where people naturally mix across research areas and career stages, making it easy to feel included from the very beginning. Umeå provides outstanding working and living conditions. This youthful city is situated beside a large river, surrounded by forests and lakes, and is near the sea. The area offers numerous opportunities for both indoor and outdoor activities.

Last updated: 16 December 2025