google-deepmind / google-deepmind/formal-conjectures
Goncharov Conjecture
- Dominant language
- Lean
- Stars
- 1.3k
- Forks
- 485
- Avg merge
- 1d 20h
- Merged PRs (30d)
- 327
Description
### What is the conjecture
For a field $F$, Goncharov's conjecture states that the cohomology of a certain motivic complex $\Gamma(F, n)$ placed in degrees $[1,n]$ is isomorphic to the motivic cohomology groups, providing a description of the algebraic K-groups $K_n(F) \otimes \mathbb{Q}$ in terms of generators and relations that generalize Milnor's K-theory. The conjecture extends Zagier's earlier conjectures on polylogarithms and relates to the Beilinson-Lichtenbaum axioms.
**Sources:**
- https://en.wikipedia.org/wiki/Goncharov_conjecture, https://arxiv.org/abs/2210.11938, https://arxiv.org/abs/2012.05599, https://www.sciencedirect.com/science/article/abs/pii/S000187082400272X, https://gauss.math.yale.edu/~ag727/polylog.pdf
### Prerequisites needed
**Formalizability Rating:** 4/5 (as of 2026-01-20)
The Goncharov conjecture requires significant infrastructure from algebraic K-theory and motivic cohomology. While Mathlib has basic commutative algebra and category theory foundations, it lacks formal definitions of: (1) motivic cohomology groups, (2) Bloch's complex and related constructions, (3) scissors congruence groups, and (4) the full apparatus of Beilinson-Lichtenbaum axioms. Additionally, the formalization would require establishing the connection between multiple polylogarithm constructions and motivic complexes. This represents substantial new theory development beyond what currently exists in Mathlib.
### [AMS categories](https://github.com/google-deepmind/formal-conjectures/labels?q=ams-)
* ams-19
* ams-14
* ams-12
### Choose either option
- [ ] I plan on adding this conjecture to the repository
- [x] This issue is up for grabs: I would like to see this conjecture added by somebody else
Created by AI, reviewed by me.
Contributor guide
Research direction
The issue names no repository files, tests, or entry points; start by reviewing existing formal-conjecture structure and the linked mathematical sources. Determine the prerequisite infrastructure needed before formalizing the conjecture, with completion requiring a formal statement supported by the required motivic and algebraic K-theory definitions.
Written by the indexing model from the issue text.
Assessment
- Domain
- devtools
- Issue type
- Feature
- Difficulty
- 5/5
- Estimated time
- Over a week
- Activity status
- Stale
- Clarity
- Needs clarification
- Newbie friendliness
- 20/100