Ben Forrás’s website

About me

Generalities

These days, I go by the name Ben Forrás, with a Germanised pronunciation [bɛn fo'ʁas]. Feel free to call me Ben. My pronouns are he/him/his in English, er/ihm in German. My full legal name is Bence Forrás, the original pronunciation of which is [ˈbɛnt͡sɛ ˈforːaːʃ].

Here is my curriculum vitæ. My ORCID iD is 0009-0009-4151-6824, and here are links to my genealogy and MathSciNet.

Current affiliation

I am a Walter Benjamin Fellow in the group of Antonio Lei at the University of Ottawa, funded by the German Research Foundation (DFG).

Publications

1. On the Wedderburn decomposition of the total ring of quotients of certain Iwasawa algebras. Preprint. arXiv
2. An equivariant p-adic Artin conjecture. International Mathematics Research Notices, Volume 2026, Issue 4, February 2026. journal arXiv MR
3. On the cohomology of plus/minus Selmer groups of supersingular elliptic curves in weakly ramified base fields. Joint with Katharina Müller. Research in Number Theory, Volume 11 (2025), article number 56. journal arXiv MR
4. Graduated orders over completed group rings and conductor formulæ. Journal of Algebra, Volume 690 (2025), pp. 114–145. journal arXiv MR
5. On the Wedderburn decomposition of the total ring of quotients of certain Iwasawa algebras II. Preprint. arXiv

Contact

• E-mail: due to a relentless barrage of unsolicited spam e-mails, my address is no longer listed here. People who actually want to reach me are probably aware of the standard methods of obtaining mathematicians’ current e-mail addresses.
• Address: University of Ottawa, Department of Mathematics and Statistics, STEM Complex, 150 Louis-Pasteur Pvt, Ottawa, Ontario, Canada K1N 6N5 (OSM)
• Office: STEM 606

Past affiliations

• 2023–2025: postdoc in Andreas Nickel's group at the Universität der Bundeswehr in München
• 2020–2023: doctoral studies at ESAGA, Universität Duisburg-Essen, Germany (as part of RTG 2553)
  Doctoral dissertation: An equivariant p-adic Artin conjecture, advisor: Andreas Nickel
• 2017–2020: MSc in Mathematics at RFWU Bonn, Germany (funded by BIGS)
  Master thesis: Iwasawa Theory, advisor: Dustin Clausen
• 2014–2017: BSc in Pure Mathematics at ELTE, Budapest, Hungary
  Bachelor thesis: Kummer’s Congruences and the p-adic Zeta-Function, advisor: Gergely Zábrádi

Events

• Motives, L-values and Eisenstein series (on the occasion of Guido Kings’s 60th birthday): September 22–26, 2025
• Iwasawa 2025: NCTS, Taiwan, June 30 – July 4, 2025
• Iwasawa Theory Taipei Summer School: National Taiwan University, 25–28 June 2025
• Automorphic forms and the Bloch–Kato conjecture: Bengaluru, 19–30 May 2025 (my poster, playlist)
• ENTR Workshop 24: Essen, 18–20 September 2024
• Algebraic Number Theory – A workshop for young researchers: UniBw München, 2–6 September 2024
• Recent Progress on Hilbert’s 12th Problem: ICMS, Bayes Centre, Edinburgh, 24–28 June 2024 (online)
• Modular Forms, L-functions, and Eigenvarieties: Paris, 18–21 June 2024
• RTG Renewal Meeting: Essen, 12–13 December 2023 (my poster)
• ITCAG Workshop: Iwasawa theory and cohomology of arithmetic groups, 27–28 November 2023
• Kleine AG on Modularity Lifting Theorems: Bonn, 9 September 2023
• QuINGs 2023: West Lexham, Norfolk, UK, 30 August – 1 September 2023
• Iwasawa 2023: in memory of John Coates: University of Cambridge, 17–21 July 2023
• Arithmetic of L-functions: Madrid, 22–26 May 2023
• Spring School on Non-archimedean Geometry and Eigenvarieties: Heidelberg, 6–17 March 2023
• Number theory meets p-adic representations: Münster, 13–17 February 2023
• Seminar on special values of L-functions: Bielefeld, September 21, 2022
• Elliptic curves and modular forms in arithmetic geometry: Milano, September 12–16, 2022
• School on Arithmetic Geometry: Essen, September 5–9, 2022
• Young Researchers in Algebraic Number Theory (Y-RANT): Glasgow, August 23–25, 2022
• Number Theory and Algebraic Geometry: ICM sectional workshop, ETH Zürich, July 11–14, 2022
• Arizona Winter School: Tucson, March 5–9, 2022
• Neubiberger Zahlentheorie-Tage Herbst 2021: Universität der Bundeswehr München, September 30 – October 1, 2021

Research talks

• Graduated orders in equivariant Iwasawa theory, Ottawa/Carleton Number Theory Seminar: Ottawa, November 24, 2025
• Signed Selmer groups of supersingular elliptic curves over weakly ramified base fields: Oberseminar Arithmetische und Algebraische Geometrie, München, January 15, 2025
• A Kida formula for plus/minus Selmer groups of supersingular elliptic curves over weakly ramified base fields, ENTR Workshop 24: Essen, September 2024
• An equivariant p-adic Artin conjecture, QuINGs 2023: West Lexham, Norfolk, UK, 31 August 2023
• Integrality of smoothed p-adic Artin L-functions, Arithmetic of L-functions: Madrid, 24 May 2023
• Integrality of smoothed p-adic Artin L-functions, Seminar des SFB/TRR 326 GAUS: Heidelberg, February 3, 2023
• Integrality of smoothed p-adic Artin L-functions, RTG seminar: Essen, January 12, 2023
• Integrality of smoothed p-adic Artin L-functions, IISc Number theory seminar: Bangalore, November 16, 2022
• Integrality of smoothed p-adic Artin L-functions, Seminar on special values of L-functions: Bielefeld, September 21, 2022
• Integrality of smoothed p-adic Artin L-functions, Young Researchers in Algebraic Number Theory (Y-RANT): Glasgow, August 23–25, 2022
• Integrality of the smoothed p-adic L-function, Neubiberger Zahlentheorie-Tage Herbst 2021: Universität der Bundeswehr München, September 30 – October 1, 2021

Local talks and notes

• Iwasawa Theory: Talk 11, Oberseminar Arithmetische Geometrie, Regensburg, July 1, 2024
• Iwasawa Theory I: Talk 11, Oberseminar Arithmetische Geometrie, Regensburg, February 8, 2024
• The Langlands Correspondence: PhD seminar, June 21, 2023
• Abstract Root Data: PhD seminar, January 25, 2023
• Weakly ramified extensions I and II: Galois module structure seminar, June 22 and 29, 2022
• Deformations of Galois representations II – lifting Galois representations: PhD seminar, July 8, 2022
• Towards the integrality of the p-adic L-function: PhD Days, October 7–8, 2021
• Discrete Adic Spaces (Globalisation I): Forschungsseminar, July 8, 2021
• Affinoid Algebras and Affinoid Spaces: PhD seminar, May 11, 2021
• Some reduction steps and the Ritter–Weiss module: Brumer–Stark seminar (archived link), December 1, 2020
• Divided Powers I: PhD seminar, November 4, 2020

Warning: my notes and slides may contain significant oversimplifications and mistakes. Use them at your own peril, and always consult the original articles and books.

Future events of possible interest