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FormalizedGeometry & formalization

Sphere packing: the proof, the code, and the people

Gauss completes major formalization work built on a community project.

Maryna Viazovska · sphere-packing community · Math, Inc. / Gauss

Start with the question

The problem

How densely can identical non-overlapping balls fill space? Viazovska solved the eight-dimensional problem in 2016; with Cohn, Kumar, Miller, and Radchenko, she also settled dimension 24. Formalizing these proofs requires geometry, harmonic analysis, and modular forms.

Dimension 8: E₈ lattice · Dimension 24: Leech lattice

01

Before the automated finish

The community project began in 2024. Its contributors built definitions, modular-form infrastructure, and a blueprint for the argument. Their own history describes contributions from many mathematicians and experiments with more than one AI tool. This groundwork is part of the achievement. [2]

02

What Gauss contributed

Math, Inc. reports that Gauss completed the remaining eight-dimensional work in five days and formalized the 24-dimensional case over two weeks. It released a roughly 200,000-line development. These are formalizations of known human theorems, rather than new discoveries of the optimal lattices. [1][3]

03

The project continues after compilation

The community describes reviewing the generated code and preparing it for integration. The project’s research paper treats the February milestone as one stage in a continuing collaboration. Maintainable definitions and reusable library results matter alongside the existence of a checked final theorem. [4][5]

Inspect the evidence

The Lean formalization

Released Lean artifact; community integration continues

Math, Inc.’s repository contains the 8- and 24-dimensional formalizations. The community project has its own maintenance and review process. A complete artifact in a company fork does not imply that all of its code has been merged into the community library.

Open the Lean project ↗

Sources & further reading

Reviewed 9 Sept 2026. X permalinks were recovered from indexed posts and linked discussions; direct X pages were not consistently accessible. They document the conversation, not proof correctness.

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