Geoffroy Horel

Professeur à Sorbonne Université.

E-mail:

Adresse:

Institut de Mathématiques de Jussieu - Paris Rive Gauche (IMJ-PRG), Sorbonne Université, 4 place Jussieu, 75252 Paris Cedex 5

Preprints

• (with Thomas Willwacher) Automorphisms of framed operads , (last update 28 Septembre 2024).
• Automorphisms of the little disks operad with p-torsion coefficients, (last update, 7 August 2019).

Published papers

• with Joana Cirici, An operadic proof of the BTT theorem, Phil. Trans. R. Soc. A (2026) 384 (2328).
• (with Pedro Boavida de Brito and Joana Cirici) Equivariant formality of the little disks operad . Forum of Math. Pi. Journal version .
• (with Joana Cirici) Formality of hypercommutative algebras of Kähler and Calabi-Yau manifolds. Journal of the European Mathematical Society, Journal version.
• E2 formality via obstruction theory, Annales Henri Lebesgue, Volume 8 (2025), pp. 699-720 Journal version.
• (with Manuel Krannich and Alexander Kupers) Two remarks on spaces of maps between operads of little cubes , Higher structures, vol. 9, no. 1, 2025, pp. 329-339 Journal version.
• Binomial rings and homotopy theory, Journal für die reine und angewandte Mathematik (Crelles Journal), vol. 2024, no. 813, 2024, pp. 283-305 Journal version.
• (with Martin Palmer) Motivic homological stability of configuration spaces, Bull. London Math. Soc. Vol. 55, Issue 2 (2023), pp. 892-913 Journal version.
• (with Joana Cirici) Étale cohomology, purity and formality with torsion coefficients , Journal of Topology, Vol. 15, Issue 4 (2022), pp. 2270-2297, Journal version.
• (with Gabriel Drummond-Cole) Homotopy transfer and formality, Annales de l'Institut Fourier, Vol.71, no.5, pp.2079-2116, Journal version.
• (with Maxime Ramzi) A multiplicative comparison of MacLane homology and topological Hochschild homology, Annals of K-theory, Vol. 6 (2021), No. 3, pp. 571-605 , Journal version.
• (with Pedro Boavida de Brito) On the formality of the little disks operads in positive characateristic, Journal of the London Mathematical Society, Volume 104, Issue 2 (2021), pp. 634-667, Journal version.
• (with Pedro Boavida de Brito) Galois symmetries of knot spaces, Compositio Mathematica , Volume 157 , Issue 5 (2021), pp. 997-1021 , Journal version.
• (with Joana Cirici) Mixed Hodge structures and formality of symmetric monoidal functors, Annales Scientifiques de l'École Normale Supérieure, Vol. 53-4 (2020), pp. 1071-1104, Journal version.
• (with Pedro Boavida de Brito and Marcy Robertson) Operads of genus zero curves and the Grothendieck-Teichmüller group, Geometry & Topology, Vol. 23-1 (2019), pp. 299-346. Journal version.
• (with Clément Dupont) On two chain models for the gravity operad, Proc. Amer. Math. Soc. 146 (2018), pp. 1895-1910. Journal version.
• Profinite completion of operads and the Grothendieck-Teichmüller group, Advances in Math. Vol. 321, (2017), pp. 326-390. Journal version.
• Factorization homology and calculus à la Kontsevich Soibelman, Journal of Noncommutative Geometry, Vol. 11, No. 2 (2017), pp. 703-740. Journal version.
• (with Ilan Barnea and Yonatan Harpaz) Pro-categories in homotopy theory, Algebraic & Geometric Topology, Vol. 17 (2017), pp. 567-643. Journal version
• (with Giovanni Caviglia) Rigidification of higher categorical structures, Algebraic & Geometric Topology, Vol. 16 (2016), pp. 3533–3562. Journal version.
• Brown categories and bicategories, Homology, Homotopy and Applications, Vol. 18 (2016), No. 2, pp. 217-232. Journal version.
• Motivic homological stability for configurations spaces of the line, Bull. London Math. Soc. 48 (2016) pp. 601-616. Journal version. (The main theorem of this paper is incorrect, here is an Erratum)
• Higher Hochschild cohomology of the Lubin-Tate ring spectrum , Algebraic & Geometric Topology, Vol. 15 (2015), pp. 3215-3252. Journal version
• A model structure on internal categories in simplicial sets, Theory and Applications of Categories, Vol. 30, No. 20, 2015, pp. 704-750. Journal version.

Miscellaneous writings

• Algebraic models and motivic structure on homotopy types, (last update, 3 November 2024).
• with Coline Emprin, Weight structures and formality, Higher Structure and Operadic Calculus, Advanced Courses in Mathematics - CRM Barcelona, Springer, 2024.
• Groupe de Galois et espace des noeuds (last update, 14 December 2018) In French, published in Actes du congrès de la SMF 2018.
• A note on p-completion of spectra (last update, 13 April 2016) This is now part of the paper Automorphisms of the little disks operad with p-torsion coefficients.
• The homotopy theory of A-infinity categories (last update, 14 March 2015)

Students

PhD students

• Nicolas Guès
• Coline Emprin

Master students

• Xuanhao Lou
• Rashiqa Dawood
• Alexis Miller
• Jinwen Xu
• Jingyuan Zhu
• Julio Perez Garcia
• Rodrigue Haya Enriquez
• Coline Emprin
• Noé Sotto
• Maxime Ramzi
• Hashem Alsabi
• Iskandar Boucharenc
• Carlos Cortez
• Gédéon Chevallier

Conferences

• Manifolds and Moduli, Lisbon, April 2026.
• Operadic Methods in Geometry II, Paris, October 2024
• Operadic Methods in Geometry I, Barcelona, November 2023
• Moduli and friends, Bucharest, September 2023
• Homotopical Methods in Algebraic Geometry, Paris, March 2023