UFOCLAN (Universal quadratic forms and class numbers) is the number theory research group at Charles UniversityFaculty of Mathematics and Physics, Department of Algebra.

Team members

  • Vita Kala (PI)
PhD students

We regularly have funding for hiring new postdocs and PhD students. Interested very strong candidates are welcome to email Vita with informal inquiries.

In particular, Vita may accept a new Ph.D. student who would start their studies in October 2023 (an earlier start is not possible). The applications for this position will be accepted from January 1 till January 31, 2023; more information will be listed here by the end of October 2022.

We’ll hire a new postdoc with starting date in the first half of 2023 (at latest July 1, 2023), see here. Informal inquiries by strong candidates are welcome (by email to Vita).


Our students Matěj Doležálek and Martin Raška both got the First Prize at the International Mathematics Competition for University Students.

Apply to our new postdoc opening! (Applications should be received ideally by Sep 15.)

Vita will give an invited series of introductory lectures on universal quadratic forms at XXIII International Workshop for Young Mathematicians in Krakow in September.

Giacomo’s and Pavlo’s paper on the potential energy of algebraic integers is accepted by J. Math. Anal. Appl.

The paper by Ester, Jakub, and Martin on Pythagoras numbers in biquadratic fields got accepted by Expositiones Math.

Pavlo will soon start a new postdoc at Aalto University, where he’ll work with Camilla Hollanti.

Our paper on large class numbers of real quadratic fields (by Andrew Granville, Ale, Giacomo, Pavlo, and Vita) got accepted by IMRN! This also gives us Erdős number 2 (thanks to Andrew).

Matěj Doležálek received the Award of The Learned Society of the Czech Republic for his work Quaternions and universal quadratic forms over number fields.


GAČR Junior Star project

from the Czech Science Foundation GAČR, 2021–2025
success rate 9%, total budget 1 000 000 USD

Primus grant

Universal quadratic forms: geometry and analysis
from Charles University, 2020–2022

GAČR Junior grant 

Quadratic forms and numeration systems over number fields
from the Czech Science Foundation GAČR, 2017–2019
outcomes of the grant were evaluated by the grant agency as excellent (top 20%)

University research center UNCE

PI Jan Krajíček
Methods of Algebra and Logic

Our seminars

Number Theory Seminar
Algebra Colloquium
If you want to give a talk in either of these seminars, please let one of the organizers (eg Vita) know!
We have mailing lists for both seminars with weekly talk announcements – if you want to join them, please also let Vita know.

Team publications

See here.

Past team members

  • Alessandro Fazzari (09–12/2021)
    next job: postdoc at American Institute of Mathematics
  • Tomáš Hejda (01/2017–12/2019)
    next job: work for Overleaf
  • Eric Nathan Stucky (08/2021–08/2022)
  • Pavlo Yatsyna (01/2020–07/2022)
    next job: postdoc at Aalto University
  • Tomáš Vávra (01/2017–08/2020)
    next job: postdoc at University of Waterloo
  • Ezra Waxman (08/2018–07/2019)
    next job: postdoc at Dresden University with Minerva Fellowship
  • Magdaléna Tinková (PhD student, 2017–2021)
    next job: tenure-track faculty at Czech Technical University, Prague