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arXiv · 2505.12933

Formalising the Bruhat-Tits Tree

Judith Ludwig·Christian Merten
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Abstract

In this article we describe the formalisation of the Bruhat-Tits tree - an important tool in modern number theory - in the Lean Theorem Prover. Motivated by the goal of connecting to ongoing research, we apply our formalisation to verify a result about harmonic cochains on the tree.

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Judith Ludwig, Christian Merten. 2025-05-19. Formalising the Bruhat-Tits Tree. https://doi.org/10.46298/afm.15738

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