My Research

Research interest 

My research is focused on  optimal transport and its applications  on functional inequalities, metric geometry, metric measure spaces etc.,  I am particularly interested in mathematics objects  related to both  metrics and measures.

So far, I have worked mainly on the following topics: 

1. optimal transport, analysis and geometry of Wasserstein space

2. metric measure space with synthetic Ricci curvature bound

3. Sobolev space on metric measure space

4. Bakry-Emery's theory, geometric and functional inequalities

Publications

[0]  (Ph.D thesis) Topics on calculus on metric measure spaces,defense on 23 June 2015 at Paris,  thesis-on-line: archives-ouvertes

[1]  (with N. Gigli) The continuity equation on metric measure spacesCal. Var. PDE. (2015)

[2]  (with N. Gigli) Independence on p of weak upper gradients on RCD spaces,  J. Funct. Anal. (2016)

[3]  (with A. Mondino) Angles between curves in metric measure spaces, Anal. Geom. Metr. Spaces.  (2017)

[4]  Ricci tensor on RCD(K,N) space, J. Geom. Anal. (2018)

[5]  (with N. Gigli)  Sobolev Spaces on Warped ProductsJ. Funct. Anal. (2018)

[6]  Conformal transformation on metric measure spacesPotential. Anal. (2019)

[7]  New characterizations of  Ricci curvature on RCD metric measure spaces Disc. Cont. Dyn. Sist. A (2018)

[8]  Characterizations of monotonicity of vector fields on metric measure space,   Cal. Var. PDE. (2018)

[9]  Sharp  p-Poincaré inequality under Measure Contraction Property,  Manuscripta  Math. (2020) 

[10]  Measure rigidity of synthetic lower Ricci curvature bound on Riemannian manifolds,   Adv. Math. (2020)

Remark: Part of this article, detailed computation for the measure-valued Ricci tension can be found in "Ricci tensor on smooth metric measure space with boundary" at: arxiv

[11]  (with E. Milman) Sharp Poincaré inequality under Measure Contraction Property,   Ann. Scuola Norm. Sup. Pisa Cl. Sci. (2021)

[12]  Rigidity of some functional inequalities on  RCD spaces,   J. Math. Pures Appl. (2021)   

[13]  (with K-T. Sturm) Curvature-dimension conditions  for diffusions under time change, Ann. Math. Pura Appl . (2022)

[14]  (with Z-F. Xu) Sharp uncertainty principles on metric measure spacesCal. Var. PDE. (2024)

[15]  On the asymptotic behaviour of the fractional Sobolev seminorms: A geometric approachJ. Funct. Anal. (2024).

[16]  (with A. Pinamonti, Z-F.Xu, K.Zambanini)  Maz’ya–Shaposhnikova Meet Bishop–Gromov, Potential. Anal. (2025).

Remark:  This is a replacement & improvement of the paper I wrote with  Andrea Pinamonti:  On the asymptotic behaviour of the fractional Sobolev seminorms in metric measure spaces: asymptotic volume ratio, volume entropy and rigidity, preprint at: arxiv



Preprints

12 Oct 2021  (with A. Pinamonti) On the asymptotic behaviour of the fractional Sobolev seminorms in metric measure spaces: Bourgain-Brezis-Mironescu's theorem revisited, preprint at: arxiv

See paper [15] above for a more  simple & direct version, for spaces with nice tangent spaces.

20 Aug 2024 [Update] Sharp and rigid isoperimetric inequality in metric measure spaces with non-negative Ricci curvature,  preprint at: arxiv.  

A new version has been updated on arxiv (08.20.2024),  we find a totally new proof to the rigidity theorem,  and the assumption on the  existence of a needle decomposition has been removed.  Though, the previous version, which includes several quantitative estimate for log-concave measures, has its own interest.

 A short version without the proof of rigidity  is here:   A  sharp isoperimetric inequality in metric measure spaces with non-negative Ricci curvature,  preprint at: arxiv

20 Aug 2024 [New Paper] ABP estimate on metric measure spaces via optimal transport,  preprint at: arxiv.  

We estabish an Alexandroff-Bakelman-Pucci (ABP) type estimate on metric measure spaces,  by dealing with an inverse problem of optimal transport,  and Otto's calculus.

2 Dec 2024  [New Paper] On the geometry of Wasserstein barycenter I,  preprint at: arxiv.  


We study the Wasserstein barycenter problem in the setting of non-compact, non-smooth extended metric measure spaces. We introduce a couple of new concepts and obtain the existence, uniqueness, absolute continuity of the Wasserstein barycenter, and prove Jensen's inequality in an abstract framework. 

This generalized several results on Euclidean space, Riemannian manifolds and Alexandrov spaces, to metric measure spaces satisfying Riemannian Curvature-Dimension condition à la Lott--Sturm--Villani, and some extended metric measure spaces including abstract Wiener spaces and configuration spaces over Riemannian manifolds. 

We also introduce a new curvature-dimesion condition, we call Barycenter-Curvature-Dimension condition BCD. We prove its stability under measured-Gromov-Hausdorff convergence and prove the existence of the Wasserstein barycenter under this new condition. In addition, we get some geometric inequalities including a multi-marginal Brunn-Minkowski inequality and a functional Blaschke-Santaló type inequality.