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Related papers: Formalising the Bruhat-Tits Tree

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To obtain the highest confidence on the correction of numerical simulation programs for the resolution of Partial Differential Equations (PDEs), one has to formalize the mathematical notions and results that allow to establish the soundness…

Logic in Computer Science · Computer Science 2024-10-03 François Clément , Vincent Martin

The first-order theory of finite and infinite trees has been studied since the eighties, especially by the logic programming community. Following Djelloul, Dao and Fr\"uhwirth, we consider an extension of this theory with an additional…

Logic in Computer Science · Computer Science 2020-08-10 Fabian Zaiser , C. -H. Luke Ong

Lie algebras are an important class of algebras which arise throughout mathematics and physics. We report on the formalisation of Lie algebras in Lean's Mathlib library. Although basic knowledge of Lie theory will benefit the reader, none…

Logic in Computer Science · Computer Science 2021-12-10 Oliver Nash

Trees are partial orders in which every element has a linearly ordered set of predecessors. Here we initiate the exploration of the structural theory of trees with the study of different notions of \emph{branching in trees} and of…

Combinatorics · Mathematics 2023-01-18 Valentin Goranko , Ruaan Kellerman , Alberto Zanardo

We formalize the multi-graded Proj construction in Lean4, illustrating mechanized mathematics and formalization.

Logic in Computer Science · Computer Science 2025-09-19 Arnaud Mayeux , Jujian Zhang

Determinisation and completion of finite tree automata are important operations with applications in program analysis and verification. However, the complexity of the classical procedures for determinisation and completion is high. They are…

Formal Languages and Automata Theory · Computer Science 2017-11-02 John P. Gallagher , Mai Ajspur , Bishoksan Kafle

The relevance of the BRST cohomology of the extended antifield formalism is briefly discussed along with standard homological tools needed for its computation.

High Energy Physics - Theory · Physics 2007-05-23 Glenn Barnich

This paper provides an overview of the theory of Bruhat-Tits buildings. Besides, we explain how Bruhat-Tits buildings can be realized inside Berkovich spaces. In this way, Berkovich analytic geometry canbe used to compactify buildings. We…

Group Theory · Mathematics 2015-03-25 Bertrand Remy , Amaury Thuillier , Annette Werner

Large-scale formalization projects in Lean rely on blueprints: structured dependency graphs linking informal mathematical exposition to formal declarations. While blueprints are central to human collaboration, existing tooling treats the…

Logic in Computer Science · Computer Science 2026-02-02 Thomas Zhu , Pietro Monticone , Jeremy Avigad , Sean Welleck

Fractional calculus is a generalization of classical theories of integration and differentiation to arbitrary order (i.e., real or complex numbers). In the last two decades, this new mathematical modeling approach has been widely used to…

Logic in Computer Science · Computer Science 2016-08-10 Umair Siddique , Osman Hasan , Sofiène Tahar

Automated theorem proving is essential for the formal verification of safety-critical systems. As the corpus of formal proofs grows, a natural paradigm is to learn from existing proofs. However, current learning-based approaches…

Software Engineering · Computer Science 2026-05-12 Jian Fang , Yixun Yao , Yingfei Xiong

Technological advancement allows information to be shared in just a single click, which has enabled the rapid spread of false information. This makes automated fact-checking system necessary to ensure the safety and integrity of our online…

Artificial Intelligence · Computer Science 2025-12-02 Anab Maulana Barik , Shou Ziyi , Yang Kaiwen , Yang Qi , Shen Xin

The purpose of this paper is to present a ``Cech-De Rham'' model for the cohomology of leaf spaces. This model lends itself to the construction of characteristic classes (in the cohomology of classifying spaces) by explicit geometrical…

Differential Geometry · Mathematics 2007-05-23 Marius Crainic , Ieke Moerdijk

We review the recent developments of the Loop-Tree Duality method, focussing our discussion on the first numerical implementation and its use in the direct numerical computation of multi-leg Feynman integrals. Non-trivial examples are…

High Energy Physics - Phenomenology · Physics 2017-09-11 G. Chachamis , G. Rodrigo

Consider matrices of order $k+N$ over $p$-adic field determined up to conjugations by elements of $GL$ over $p$-adic integers. We define a product of such conjugacy classes and construct the analog of characteristic functions (transfer…

Algebraic Geometry · Mathematics 2017-08-08 Yury A. Neretin

Let $\wh K$ be the field of formal Laurent series in $X^{-1}$ over the finite field $k$, and let $A$ be the ring of polynomials in $X$ over $k$. One of the main results of the paper is to give a particularly nice coding of the geodesic flow…

Group Theory · Mathematics 2016-08-16 Anne Broise , Frédéric Paulin

Python's typing system has evolved pragmatically into a powerful but theoretically fragmented system, with scattered specifications. This paper proposes a formalization to address this fragmentation. The central contribution is a formal…

Programming Languages · Computer Science 2025-09-17 Andrei Nacu , Dorel Lucanu

We introduce the notion of ideal triangle in the Bruhat-Tits building associated to a split group -- it is analogous to the usual notion of triangle, but one vertex is "at infinity" in a certain direction. We prove that the algebraic…

Representation Theory · Mathematics 2010-12-01 Thomas J. Haines , Michael Kapovich , John J. Millson

We describe the formalization of the existence and uniqueness of Haar measure in the Lean theorem prover. The Haar measure is an invariant regular measure on locally compact groups, and it has not been formalized in a proof assistant…

Logic in Computer Science · Computer Science 2021-02-16 Floris van Doorn

The goal of this paper is to refine some aspects of the cohomological study of Bruhat-Tits subgroups. It aims to complement the work done in the 1987 article. As an application, we obtain a result "\`a la Grothendieck-Serre" for Bruhat-Tits…

Group Theory · Mathematics 2025-09-23 Anis Zidani