Geometric embedding for regularity structures
[Plongement géométrique pour les structures de régularité]
Annales de la Faculté des sciences de Toulouse : Mathématiques, Série 6, Tome 35 (2026) no. 2, pp. 409-436

In this paper, we show how one can view certain models in regularity structures as some form of geometric rough paths. This is performed by identifying the deformed Butcher–Connes–Kreimer Hopf algebra with a quotient of the shuffle Hopf algebra which is the structure underlying the definition of a geometric rough path. This provides an extension of the isomorphism between the Butcher–Connes–Kreimer Hopf algebra and the shuffle Hopf algebra. This new algebraic result relies strongly on the deformation formalism and the post-Lie structures introduced recently in the context of regularity structures.

Dans cet article, on montre comment l’on peut voir certains modèles dans les structures de régularité sous la forme de chemins rugueux géométriques. On réalise cette construction en identifiant l’algèbre de Hopf de Butcher–Connes–Kreimer déformée avec le quotient d’une algèbre de shuffle qui est une structure présente dans la définition d’un chemin rugueux géométrique. Cela procure une extension de l’isomorphisme entre l’algèbre de Hopf de Butcher–Connes–Kreimer et celle de l’algèbre de shuffle. Ce résultat algébrique nouveau repose fortement sur le formalisme de déformation et la structure post-Lie introduite récemment dans le contexte des structures de régularité.

Reçu le :
Accepté le :
Publié le :
DOI : 10.5802/afst.1851
Classification : 60L70, 60H15
Keywords: Hopf algebras, geometric rough paths, regularity structures, singular SPDEs, shuffle algebra
Mots-clés : Algèbres de Hopf, Algèbre de shuffle, Chemins rugueux géométriques, EDPS singulières, Structures de régularité

Yvain Bruned  1   ; Foivos Katsetsiadis  2

1 Universite de Lorraine, CNRS, IECL, 54000 Nancy, France
2 ITI-CERTH, Thermi-Thessaloniki, Greece
Licence : CC-BY 4.0
Droits d'auteur : Les auteurs conservent leurs droits
Yvain Bruned; Foivos Katsetsiadis. Geometric embedding for regularity structures. Annales de la Faculté des sciences de Toulouse : Mathématiques, Série 6, Tome 35 (2026) no. 2, pp. 409-436. doi: 10.5802/afst.1851
@article{AFST_2026_6_35_2_409_0,
     author = {Yvain Bruned and Foivos Katsetsiadis},
     title = {Geometric embedding for regularity structures},
     journal = {Annales de la Facult\'e des sciences de Toulouse : Math\'ematiques},
     pages = {409--436},
     year = {2026},
     publisher = {Universit\'e de Toulouse, Toulouse},
     volume = {Ser. 6, 35},
     number = {2},
     doi = {10.5802/afst.1851},
     language = {en},
     url = {https://afst.centre-mersenne.org/articles/10.5802/afst.1851/}
}
TY  - JOUR
AU  - Yvain Bruned
AU  - Foivos Katsetsiadis
TI  - Geometric embedding for regularity structures
JO  - Annales de la Faculté des sciences de Toulouse : Mathématiques
PY  - 2026
SP  - 409
EP  - 436
VL  - 35
IS  - 2
PB  - Université de Toulouse, Toulouse
UR  - https://afst.centre-mersenne.org/articles/10.5802/afst.1851/
DO  - 10.5802/afst.1851
LA  - en
ID  - AFST_2026_6_35_2_409_0
ER  - 
%0 Journal Article
%A Yvain Bruned
%A Foivos Katsetsiadis
%T Geometric embedding for regularity structures
%J Annales de la Faculté des sciences de Toulouse : Mathématiques
%D 2026
%P 409-436
%V 35
%N 2
%I Université de Toulouse, Toulouse
%U https://afst.centre-mersenne.org/articles/10.5802/afst.1851/
%R 10.5802/afst.1851
%G en
%F AFST_2026_6_35_2_409_0

[1] Ismaël F. Bailleul; Yvain Bruned Parametrization of renormalized models for singular stochastic PDEs, Kyoto J. Math., Volume 64 (2024) no. 4, pp. 829-854 | DOI | Zbl | MR

[2] Ismaël F. Bailleul; Masato Hoshino A tourist’s guide to regularity structures and singular stochastic PDEs, EMS Surv. Math. Sci., Volume 13 (2026) no. 1, pp. 215-354 | DOI | MR | Zbl

[3] Horatio Boedihardjo; Ilya Chevyrev An isomorphism between branched and geometric rough paths, Ann. Inst. Henri Poincaré, Probab. Stat., Volume 55 (2019) no. 2, pp. 1131-1148 | DOI | Zbl | MR

[4] Nikolaĭ N. Bogoliubow; Ostap S. Parasiuk Über die Multiplikation der Kausalfunktionen in der Quantentheorie der Felder, Acta Math., Volume 97 (1957), pp. 227-266 | DOI | Zbl | MR

[5] Yvain Bruned Renormalisation from non-geometric to geometric rough paths, Ann. Inst. Henri Poincaré, Probab. Stat., Volume 58 (2022) no. 2, pp. 1078-1090 | DOI | Zbl | MR

[6] Yvain Bruned; Ajay Chandra; Ilya Chevyrev; Martin Hairer Renormalising SPDEs in regularity structures, J. Eur. Math. Soc., Volume 23 (2021) no. 3, pp. 869-947 | DOI | Zbl | MR

[7] Yvain Bruned; Ilya Chevyrev; Peter K. Friz Examples of renormalized sdes, Stochastic Partial Differential Equations and Related Fields (Springer Proceedings in Mathematics & Statistics), Volume 229, Springer, 2018, pp. 303-317 | DOI | Zbl

[8] Yvain Bruned; Ilya Chevyrev; Peter K. Friz; Rosa Preiß A rough path perspective on renormalization, J. Funct. Anal., Volume 277 (2019) no. 11, 108283, 60 pages | DOI | Zbl | MR

[9] Yvain Bruned; Charles Curry; Kurusch Ebrahimi-Fard Quasi-shuffle algebras and renormalisation of rough differential equations, Bull. Lond. Math. Soc., Volume 52 (2020) no. 1, pp. 43-63 | DOI | Zbl | MR

[10] Yvain Bruned; Martin Hairer; Lorenzo Zambotti Algebraic renormalisation of regularity structures, Invent. Math., Volume 215 (2019) no. 3, pp. 1039-1156 | DOI | Zbl | MR

[11] Yvain Bruned; Martin Hairer; Lorenzo Zambotti Renormalisation of Stochastic Partial Differential Equations, Eur. Math. Soc. Newsl., Volume 115 (2020) no. 3, pp. 7-11 | DOI | Zbl | MR

[12] Yvain Bruned; Foivos Katsetsiadis Post-Lie algebras in Regularity Structures, Forum Math. Sigma, Volume 11 (2023), e98, 20 pages | DOI | Zbl | MR

[13] Yvain Bruned; Foivos Katsetsiadis Ramification of Volterra-type Rough Paths, Electron. J. Probab., Volume 28 (2023), 7, 25 pages | DOI | Zbl | MR

[14] Yvain Bruned; Dominique Manchon Algebraic deformation for (S)PDEs, J. Math. Soc. Japan, Volume 75 (2023) no. 2, pp. 485-526 | DOI | Zbl | MR

[15] Yvain Bruned; Katharina Schratz Resonance based schemes for dispersive equations via decorated trees, Forum Math. Pi, Volume 10 (2022), E2, 76 pages | DOI | Zbl | MR

[16] John C. Butcher An algebraic theory of integration methods, Math. Comput., Volume 26 (1972), pp. 79-106 | DOI | Zbl | MR

[17] Ajay Chandra; Martin Hairer An analytic BPHZ theorem for regularity structures (2018) | arXiv | Zbl

[18] Frédéric Chapoton Free pre-Lie algebras are free as Lie algebras, Can. Math. Bull., Volume 53 (2010) no. 3, pp. 425-437 | DOI | Zbl | MR

[19] Alain Connes; Dirk Kreimer Hopf algebras, renormalization and noncommutative geometry, Commun. Math. Phys., Volume 199 (1998) no. 1, pp. 203-242 | DOI | Zbl | MR

[20] Alain Connes; Dirk Kreimer Renormalization in quantum field theory and the Riemann–Hilbert problem I: the Hopf algebra structure of graphs and the main theorem, Commun. Math. Phys., Volume 210 (2000) no. 1, p. 249-73 | DOI | Zbl | MR

[21] Kurusch Ebrahimi-Fard; Alexander Lundervold; Hans Z. Munthe-Kaas On the Lie enveloping algebra of a post-Lie algebra, J. Lie Theory, Volume 25 (2015) no. 4, pp. 1139-1165 | Zbl | DOI | MR

[22] Loïc Foissy Finite dimensional comodules over the hopf algebra of rooted trees, J. Algebra, Volume 255 (2002) no. 1, pp. 89-120 | DOI | Zbl | MR

[23] Loïc Foissy Algebraic structures on typed decorated rooted trees, SIGMA, Symmetry Integrability Geom. Methods Appl., Volume 17 (2021), 86, 28 pages | DOI | Zbl | MR

[24] Peter K. Friz; Martin Hairer A Course on Rough Paths. With an introduction to regularity structures, Universitext, Springer, 2020 | DOI | Zbl | MR

[25] Robert Grossman; Richard G. Larson Hopf algebraic structure of families of trees, J. Algebra, Volume 126 (1989) no. 1, pp. 184-210 | DOI | Zbl | MR

[26] Massimiliano Gubinelli Controlling rough paths, J. Funct. Anal., Volume 216 (2004) no. 1, pp. 86-140 | DOI | Zbl | MR

[27] Massimiliano Gubinelli Ramification of rough paths, J. Differ. Equations, Volume 248 (2010) no. 4, pp. 693-721 | DOI | Zbl | MR

[28] Daniel Guin; Jean-Michel Oudom On the Lie enveloping algebra of a pre-Lie algebra, J. K-Theory, Volume 2 (2008) no. 1, pp. 147-167 | DOI | Zbl

[29] Martin Hairer A theory of regularity structures, Invent. Math., Volume 198 (2014) no. 2, pp. 269-504 | DOI | Zbl | MR

[30] Martin Hairer; David Kelly Geometric versus non-geometric rough paths, Ann. Inst. Henri Poincaré, Probab. Stat., Volume 51 (2015) no. 1, pp. 207-251 | DOI | Zbl | Numdam | MR

[31] Klaus Hepp On the equivalence of additive and analytic renormalization, Commun. Math. Phys., Volume 14 (1969), pp. 67-69 | DOI | Zbl | MR

[32] Pablo Linares; Felix Otto; Markus Tempelmayr The structure group for quasi-linear equations via universal enveloping algebras, Commun. Am. Math. Soc., Volume 3 (2023), pp. 1-64 | DOI | Zbl | MR

[33] Jean-Louis Loday; María Ronco Combinatorial Hopf algebras, Quanta of maths (Clay Mathematics Proceedings), Volume 11, American Mathematical Society, 2010, pp. 347-383 | Zbl

[34] Terry J. Lyons Differential equations driven by rough signals, Rev. Mat. Iberoam., Volume 14 (1998) no. 2, pp. 215-310 | DOI | Zbl | MR

[35] Terry J. Lyons; Nicolas Victoir An extension theorem to rough paths, Ann. Inst. Henri Poincaré, Anal. Non Linéaire, Volume 24 (2007) no. 5, pp. 835-847 | DOI | Zbl | Numdam | MR

[36] Ander Murua The Hopf Algebra of Rooted Trees, Free Lie Algebras, and Lie Series, Found. Comput. Math., Volume 6 (2006) no. 4, pp. 387-426 | DOI | Zbl | MR

[37] Ander Murua; Jesús M. Sanz-Serna Word series for dynamical systems and their numerical integrators, Found. Comput. Math., Volume 17 (2017) no. 3, pp. 675-712 | DOI | Zbl | MR

[38] Felix Otto; Jonas Sauer; Scott A. Smith; Hendrik Weber A priori bounds for quasi-linear SPDEs in the full sub-critical regime, J. Eur. Math. Soc., Volume 27 (2025) no. 1, pp. 71-118 | DOI | Zbl | MR

[39] Jean-Michel Oudom; Daniel Guin Sur l’algèbre enveloppante d’une algèbre pré-Lie, Comptes Rendus. Mathématique, Volume 340 (2005) no. 5, pp. 331-336 | DOI | Zbl | Numdam

[40] Nikolas Tapia; Lorenzo Zambotti The geometry of the space of branched rough paths, Proc. Lond. Math. Soc. (3), Volume 121 (2020) no. 2, pp. 220-251 | DOI | Zbl | MR

[41] Wolfhart Zimmermann Convergence of Bogoliubov’s method of renormalization in momentum space, Commun. Math. Phys., Volume 15 (1969), pp. 208-234 | DOI | Zbl | MR

Cité par Sources :