A lower bound of a sub-quotient of the Lie algebra associated to Grothendieck-Teichmüller group

A lower bound of a sub-quotient of the Lie algebra associated to Grothendieck-Teichmüller group

Formal & Physical Sciences Mathematics PBMathematicsPBFAlgebra
🎙 Prof. Benjamin Enriquez 👥 2K 📅 December 15, 2025 ⏱ 89 min 👁 112 📄 original study 🧭 2026-08-15
Available in: English (current) Français

Keywords

Grothendieck-Teichmüller groupLie algebradepth filtrationdouble shufflemodular homology

Summary

The talk by Prof. Benjamin Enriquez presents recent work on a lower bound for a sub-quotient of the Lie algebra associated to the Grothendieck-Teichmüller group. The speaker introduces the context: the sequence of embeddings of Lie algebras (double shuffle, K, GRT) and the depth filtration. He recalls the conjectural equality of these algebras and the known results on the dimensions of graded pieces. The main result is the construction of an upper bound space for the depth-graded pieces of GRT, defined via conditions on polynomials. The speaker explains the strategy: using the kernel of a map from the free Lie algebra to an infinitesimal braid algebra, and relating it to modular homology. He gives explicit examples for depths 2 and 3, and discusses the relation with linear double shuffle spaces. The talk concludes with open questions about the equality of these spaces.

142 words

Critical Evaluation

Value of the Information & Strength of the Argument

The talk presents original research with a clear logical structure. The speaker builds the argument step by step, starting from known results and conjectures, then introducing the new construction. The use of examples and explicit formulas strengthens the presentation. The discussion with the audience clarifies technical points and highlights open questions, showing the depth of the subject. The argumentation is solid, relying on established results and computational evidence.

Scientific Rigor, Source Quality, Title Accuracy

The talk is scientifically rigorous, with careful definitions and proofs sketched. The speaker cites several works, including those by Goncharov, Brown, and others, but does not provide explicit references in the video. The title accurately reflects the content. The talk is part of a workshop at the Newton Institute, indicating a high level of expertise. The audience interaction shows engagement with the material, but no comments are provided for analysis.

153 words

Title / Content Match

The title accurately describes the content: the talk focuses on a lower bound for a sub-quotient of the Lie algebra associated to the Grothendieck-Teichmüller group.

Quality & Reliability

8/10

Talk by a leading expert in the field, presenting recent research with detailed technical content. The discussion includes conjectures and known results, but the presentation is rigorous and the methods are clearly explained. The video is a seminar recording, so the quality is high, though the technical level limits accessibility.

Key Moments

Cited Sources

Concurring Sources

Contribution & Novelties

The talk presents a new upper bound for the depth-graded pieces of the Grothendieck-Teichmüller Lie algebra, constructed via conditions on polynomials. This provides a concrete space that conjecturally coincides with the linear double shuffle space, offering a new approach to studying the depth filtration. The method uses the kernel of a map to an infinitesimal braid algebra and relates to modular homology.

Pour aller plus loin :

97 words

Radar Profile

The radar profile shows high scores in technical level and information quality, reflecting the advanced nature of the talk. The lower score in quantity of information is due to the specialized topic and limited accessibility. Overall, the talk is highly rigorous and informative for experts.

Reliability 8/10