Fukuhiro Ueda

Research Institute for Mathematical Sciences (RIMS), Kyoto University

Research

My research is in arithmetic geometry and number theory. I work on p-adic Hodge theory, Galois representations, and Langlands Correspondence.

Preprints

Formalization of Langlands’s Second Main Lemma for Local Epsilon Factors

Fukuhiro Ueda · 2026

A Lean 4 formalization of Langlands’s Second Main Lemma following the companion local proof. The First Main Lemma gives only a power relation; the formalization verifies the further ramification analysis, including the mathematically new wild dyadic case.

A Local Proof of Langlands’s Second Main Lemma for Local Epsilon Factors over Nonarchimedean Local Fields

Fukuhiro Ueda · 2026

A local proof of Langlands’s Second Main Lemma in mixed and equal characteristic. The new point is the wild dyadic case, where the remaining sign is determined by comparing the finite sums in Lamprecht’s formula.

Formalization of Langlands’s First Main Lemma for Local Epsilon Factors

Fukuhiro Ueda · 2026

A Lean 4 formalization of the First Main Lemma following the companion local proof, including local constants, ramification and finite-field identities, stationary classes, and the full case analysis.

A Local Proof of Langlands’s First Main Lemma for Local Epsilon Factors over Nonarchimedean Local Fields

Fukuhiro Ueda · 2026

A complete purely local proof of Langlands’s First Main Lemma in both mixed and equal characteristic, reconstructing the Dwork–Langlands method and completing the missing endpoint, non-stable wild, and quadratic calculations.

Published papers

Crystalline comparison isomorphisms in p-adic Hodge theory: the absolutely unramified case

with Jilong Tong · Algebra & Number Theory 13 (2019), no. 7, 1509–1581

Constructs crystalline comparison isomorphisms for proper smooth formal schemes over an absolutely unramified base, allowing nontrivial coefficients and a relative version, using the pro-étale site.

The Breuil–Mézard conjecture for non-scalar split residual representations

with Yongquan Hu · Annales Scientifiques de l’École Normale Supérieure 48 (2015), no. 6, 1383–1421

Proves the Breuil–Mézard conjecture for split non-scalar residual representations of the local Galois group by local methods; together with earlier cases this completes the conjecture for p ≥ 5. As a consequence, it removes the remaining local restriction in Kisin’s proof of the Fontaine–Mazur conjecture, yielding the corresponding two-dimensional modularity theorem.

Overconvergent Families of Siegel–Hilbert Modular Forms

with Chung Pang Mok · Canadian Journal of Mathematics 67 (2015), no. 4, 893–922

Constructs one-parameter families of overconvergent Siegel–Hilbert modular forms, with applications to Galois representations attached to automorphic forms of non-cohomological weights.

Modularity of Calabi–Yau varieties and conformal field theory

Science in China Series A: Mathematics 51 (2008), no. 6, 1135–1146

Studies modularity of Calabi–Yau varieties from the viewpoint of conformal field theory, expressing the modular forms of one-dimensional Calabi–Yau orbifolds as products of Dedekind eta functions.

Thesis

Families of p-adic Galois Representations

Ph.D. thesis, Massachusetts Institute of Technology, 2011 · advisor: Barry Mazur

Generalizes Kisin’s theory of finite-slope subspaces to arbitrary p-adic fields and studies finite-slope deformation rings, local Galois eigenvarieties, their geometry near de Rham points, and an infinite fern in local Galois deformation space.