Talks and Presentations

Talks

2023

• Signed graphs as a tool for studying the linear and nonlinear graph eigenvalue problems
  online seminar, School of Mathematical (Zhuhai), Sun Yat-sen University, May 31, 2023.
  
  
• Curvature, diameter and eigenvalues of amply regular graphs
  SEU Yau Center Geometry and PDE Seminar, Shing-Tung Yau Center of Southeast University, May 18, 2023.
  
  
• Discrete gradient estimates and applications to graph theory
  Workshop on Geometric analyis (2023 Spring), School of Mathematics and Statistics, Henan University of Science and Technology, April 9, 2023.
  
  
• Signed graphs as a tool for studying the linear and nonlinear graph eigenvalue problems
  Nonlinear analysis and mathematical physcis seminar, School of Mathematical Sciences, Peking University, March 23, 2023.
  
  
• Curvature, diameter and eigenvalues of amply regular graphs
  山东大学珠峰讲坛第609期, School of Mathematics, Shandong University, March 23, 2023.
  
  
• Curvature, diameter and eigenvalues of amply regular graphs
  Seminars, online talk, Beijing Normal University, January 12, 2023.
  
  

2022

• Nodal domain theorems on signed graphs
  2022 Fudan-USTC Workshop on Spectral Geometry, online talk, December 4, 2022.
  
  
• Signed graphs and Nodal domain theorems for symmetric matrices
  Online seminar talk, Northeast Normal University, November 28, 2022.
  
  
• Curvature, diameter and eigenvalues of amply regular graphs
  Online seminar talk, Guangdong University of Technology, November 25, 2022.
  
  
• Signed graphs and Nodal domain theorems for symmetric matrices
  SCMS Combinatorics Seminar, online talk, Shanghai Center for Mathematical Sciences, September 23, 2022.
  
  
• Signed graphs and Nodal domain theorems for symmetric matrices
  Applied Geometry for Data Sciences, online talk, Mathematical Science Research Center, Chongqing University of Technology, July 27, 2022.
  
  
• Bakry-Émery curvature matrices for discrete magnetic Laplacians
  Future directions in graph curvature 2022, online talk, Newcastle University and Durham University, July 23, 2022
  
  
• p-Laplacians on graphs: basics and problems
  2022几何分析研讨会, Chaohu University, July 23, 2022
  
  
• Geometric and spectral theory of signed graphs
  山东大学数学学院珠峰论坛第518期, online talk, School of Mathematics, Shandong University, June 01, 2022
  
  
• Geometric and spectral theory of signed graphs
  丘成桐中心校庆系列学术报告, online talk, Shing-Tung Yau center of Southeast University, May 26, 2022
  
  
• Geometric and spectral theory of signed graphs
  Mathematical Concepts in the Sciences and Humanities, a conference in honor of Jürgen Jost's 65th Birthday, online talk, MPI MIS Leipzig, May 20, 2022
  
  
• Signed graphs and Nodal domain theorems for symmetric matrices
  走向现代数学学术报告 (No. 501), online talk, Department of Mathematics, Shantou University, April 15, 2022
  
  

2021

• Discrete Ricci curvatures of graphs: The computation side
  北航微分几何讨论班 (Beihang Differential Geometry Seminar), online talk, November 16, 2021
  
  
• Bakry-Émery curvature on graphs as eigenvalue problem
  2021 Differential Goemetry Conference in Shing-Tung Yau center of Southeast University, online talk, Southeast University, Nanjing, October 15, 2021
  
  
• Bakry-Émery curvature on graphs as eigenvalue problem
  黎曼几何中分析与变分问题研讨会, Zhejiang University, Hangzhou, October 11, 2021
  
  
• Bakry-Émery curvature on graphs as eigenvalue problem
  International conference and summer school on applied topology, online talk, Hebei Normal University, Shijiazhuang, August 1, 2021
  
  
• Bakry-Émery curvature on graphs as eigenvalue problem
  2021梅州青年几何分析研讨会, Sun Yat-sen University and Jiaying University, Meizhou, July 30, 2021
  
  
• The computation of discrete Ricci curvatures of amply regular graphs
  Seminar, online talk, Hunan University, June 07, 2021
  
  
• Bakry-Émery curvature on graphs as eigenvalue problem
  2021年武汉大学青年几何分析研讨会 (2021 Workshop of Young geometric analysts at Wuhan University), online talk, Wuhan University, May 16, 2021
  
  
• Bakry-Émery curvature on graphs as eigenvalue problem
  2021组合、代数与几何学术研讨会 (2021 Workshop on combinatorics, algebra and geometry), Center for Combinatorics, Nankai University, April 18, 2021
  
  
• The computation of discrete Ricci curvatures of amply regular graphs
  离散几何讨论班 (Seminar on discrete geometry), online talk, March 25, 2021
  
  

2020

• Ricci flatness and discrete curvatures of graphs
  RUC几何分析研讨班第15期 (RUC Seminar on geometric analysis), online talk, Renmin University of China, December 31, 2020
  
  
• Hypercubes, spherical graphs and discrete Ricci curvature
  Online seminar, Shandong University (Weihai), December 22, 2020
  
  
• Hypercubes, spherical graphs and discrete Ricci curvature
  Online seminar, Nankai University, October 29, 2020
  
  
• Ricci flatness and discrete curvatures of graphs
  2020 四川大学代数组合研讨会 (2020 Workshop on Algebraic Combinatorics), online conference, Sichuan University, July 11, 2020
  
  

2019

• Discrete Ricci curvature of Yann Ollivier
  the International conference on "Analysis and PDEs on Manifolds and Fractals", Nankai University, China, September 25, 2019
  
  
• Spherical graphs and discrete curvature notions
  The International Conference and PhD-Master Summer School: Groups and Graphs, Designs and Dynamics (G2D2), China Three Gorges University, Yichang, August 24, 2019.
  
  
• Discrete Ricci curvature and related graph classification problems
  the 8th International Congress of Chinese Mathematicians (ICCM 2019), Tsinghua University, Beijing, June 13, 2019.
  
  
• Discrete Ricci curvature of Yann Ollivier
  Workshop of geometric analysis on graphs, Tsinghua University, Beijing, June 07, 2019.
  
  
• Discrete Ricci curvature of Yann Ollivier
  2019东南大学青年几何分析会议, Southeast University, Nanjing, May 25, 2019.
  
  
• Discrete Lichnerowicz eigenvalue estimates and related rigidity problems
  Workshop on selected topics in Geometric analysis (2019-II), Fujian Normal University, Fuzhou, April 27, 2019.
  
  
• Discrete Ricci curvature of Ollivier
  2019中山大学-中科大微分几何研讨会 (2019 SYSU-USTC Seminar on Differential Geometry), University of Science and Technology of China, Hefei, April 13, 2019.
  
  

2018

• What are discrete spheres?
  几何分析讨论班, Zhejiang University, December 28, 2018.
  
  
• A discrete curvature approach to strongly spherical graphs
  Guangzhou Discrete Mathematics Seminar, Sun Yat-sen University, Guangzhou, December 14, 2018.
  
  
• What are discrete spheres?
  Differential Geometry Youth Forum in Beijing 2018, Beijing Normal University, December 2, 2018.
  
  
• What are discrete spheres?
  ECNU Differential Geometry Seminar , East China Normal University, November 14, 2018.
  
  
• What are discrete spheres?
  微分几何与几何分析讨论班, Nanjing University, October 12, 2018.
  
  
• What are discrete spheres?
  School of Mathematics and Statistics, Wuhan University, September 14, 2018.
  
  
• What are discrete spheres?
  The 4th Workshop on Differential Geometry and Differential Equations, Suzhou Campus, Renmin University of China, September 1, 2018.
  
  
• Classification results for graphs with Ricci curvature restrictions
  School of Mathematical Sciences, Fudan University, May 28, 2018.
  
  
• Discrete Bonnet-Myers Theorem and rigidity properties of hypercubes
  "2018中科大-中山大学微分几何研讨会"(2018 USTC-SYSU Joint Workshop on Differential Geometry), School of Mathematics, Sun Yat-sen University, Guangzhou, Marhc 04, 2018.
  
  
• Discrete Bonnet-Myers Theorem and rigidity properties of hypercubes
  Young Geometric Analysts’ Forum 2018, TSIMF, Sanya, Feburary 02, 2018.
  
  

2017

• Magnetic sparseness and Schrödinger operators on graphs
  Final Conference: Discrete and Continuous Models in the Theory of Networks, ZiF, Bielefel University, November 27-December 1, 2017.
  
  
• Discrete Bonnet-Myers Theorem and rigidity properties of hypercubes
  Seminars, Shandong University, Ji'nan, November 03, 2017.
  
  
• Discrete Bonnet-Myers Theorem and rigidity properties of hypercubes
  TM02 Geometry and Topology, Chinese Mathematical Society 2017 Annual Conference, Xiangtan, October 20-24, 2017.
  
  
• Magnetic sparseness and Schrödinger operators on graphs
  International Conference "Analysis and PDEs on Manifolds", Nankai University, Tianjin, September 21-23, 2017.
  
  
• Random metric partitions and higher order eigenvalue estimates
  The Conference on Harmonic Analysis, 2017, University of Science and Technology of China, Hefei, May 28-June 3, 2017.
  
  
• Discrete Bonnet-Myers Theorem
  Workshop on Geometry, Analysis and Quantum information, Shanghai Jiao Tong University, April 22-23, 2017.
  
  
• Bakry-Émery curvature functions of graphs
  Workshop on Curvatures of Graphs, Simplicial Complexes and Metric Spaces, Tsinghua Sanya International Mathematics Forum, Sanya, Hainan, China, March 13-17, 2017.
  
  
• Bakry-Émery curvature functions of graphs (two 1.5hr lectures)
  Workshop on aspects of graph theory, Fudan University, Shanghai, China, Feburary 13-18, 2017.
  
  
• Discrete Cheeger inequalities and their applications
  “2016中山大学-中科大微分几何研讨会” （USTC-SYSU Joint Workshop on Differential Geometry) USTC, Hefei, January 06, 2017.
  
  

2016

• Ricci curvature and eigenvalue estimates for discrete and continuous magnetic Laplacian
  “第四次青年几何分析小组会议” （The Fourth workshop of Young geometric analysts), Renmin University of China, Beijing, December 31, 2016.
  
  
• Ricci curvature and eigenvalues estimates for discrete and continuous magnetic Laplacian
  Workshop on spectral geometry, Fudan University, Shanghai, China, December 22-23, 2016.
  
  
• Structural balance theory and Cheeger inequalities of signed graphs
  The 8th AHU-USTC Joint Seminar on Algebraic Combinatorics, Anhui University, Hefei, China, December 10, 2016.
  
  
• Cheeger constant, spectral clustering and eigenvalue ratios of Laplacian
  Workshop on Geometric analysis, Wuhan University, Wuhan, China, December 5, 2016.
  
  
• Ricci curvature and eigenvalue estimates for magnetic Laplacian
  Mini-Workshop on Geometry & PDE, Xiamen University, Xiamen, China, November 13, 2016.
  
  
• Buser inequalities for graph connection Laplacian
  Center for Combinatorics, Nankai University, Tianjin, China, November 05, 2016.
  
  
• Cheeger inequalities on signed graphs
  School of Mathematical Sciences, Nanjing Normal University, Nanjing, China, November 03, 2016.
  
  
• Multiway dual Cheeger constants and spectral bounds of graphs
  School of Mathematics and Statistics, Nanjing University of Information Science and Technology, Nanjing, China, November 02, 2016.
  
  
• Frustration index of magnetic graphs and spectral clustering for oriented graphs
  Workshop on discrete analysis, Fudan University, Shanghai, China, August 13-14, 2016.
  
  
• Bakry-Émery curvature functions of graphs (video)
  BIRS workshop Algebraic and Spectral Graph Theory, Banff, Albert, Canada, July 31-August 5, 2016.
  
  
• Higher order Buser inequalities for the graph connection Laplacian
  7ECM satellite event Heat Kernels and Analysis on Manifolds and Fractals, Bielefeld University, July 15, 2016.
  
  
• Ricci curvature and eigenvalue estimate for the magnetic Laplacian on manifolds
  Forschungsseminar Diskrete Spektraltheorie, Institute für Mathematik, Der Universität Potsdam, July 5, 2016.
  
  
• Higher order Buser inequalities for the graph connection Laplacian
  EPSRC Workshop Geometry and Computation on Groups and Complexes, Newcastle University, June 6, 2016.
  
  

2015

• Cheeger inequalities for magnetic Laplacians on graphs and manifolds
  FUDAN-USTC Joint Workshop on Spectral Geometry, Fudan University, Shanghai, and University of Science and Technology of China, Hefei, China, December 12, 2015.
  
  
• Cheeger inequalities for signed Laplacians
  Seminar & Colloquia (hosted by Prof. Yaokun Wu), Department of Mathematics, Shanghai Jiao Tong University, Shanghai, China, December 8, 2015.
  
  
• Cheeger constants and Eigenvalue ratios of the Laplacian
  Differential Geometry Seminar, Graduate Center, City University of New York, November 5, 2015.
  
  
• Signed Laplacians and Spectral Clustering Via Quotient Space Metrics
  MS6: Recent Spectral Approaches for Graph Clustering, SIAM Conference on Applied Linear Algebra, Hyatt Regency Atlanta, Atlanta, Georgia, USA, October 26, 2015.
  
  
• Cheeger constant, spectral clustering and eigenvalue ratios of Laplacian
  Non-Combinatorial Combinatorics, Mathematics Institute, University of Warwick, September 16, 2015.
  
  
• Higher order Cheeger inequalities for discrete magnetic Laplacians
  Vortragsreihe Seminar über Mathematische Physik und Funktionalanalysis , FernUniversität in Hagen, Germnay, July 15, 2015.
  
  
• Eigenvalues of magnetic Laplacians on graphs and manifolds: Cheeger inequalities and Ramanujan property
  Oberseminar Differentialgeometrie, Max Planck Institute for Mathematics, Bonn, Germnay, July 9, 2015.
  
  
• Cheeger inequalities for magnetic Laplacians
  Oberseminar Geometric Analysis, University of Bielefeld, Germany, June 2, 2015.
  
  
• Cheeger constant, spectral clustering and eigenvalue ratios of Laplacian
  Seminar (Dr. Han Xiaoli), Department of Mathematical Sciences, Tsinghua University, China, March 1, 2015
  
  
• Cheeger constants with signatures and spectral clustering via quotient space metrics
  Mini-workshop: Discrete p-Laplacians: Spectral Theory and Variantional Methods in Mathematics and Computer Science, MFO, Oberwolfach, Germany, Februrary 8-14, 2015
  
  

2014

• Eigenvalue ratios on closed Riemannian manifolds with nonnegative Ricci curvature
  Oberseminar Geometric Analysis, University of Bielefeld, Germany, November 18, 2014.
  
  
• Cheeger constant, spectral clustering and eigenvalue ratios of Laplacian (slides)
  Algebra-Geometry seminar, School of Mathematics & Statistics, Newcastle University, October 21, 2014
  
  
• Spectral clustering via metrics of projective spaces
  Summer Session 2014 ZiF cooperation group "Discrete and Continuous Models in the Theory of Networks",
  ZiF, University of Bielefeld, Germany, July 29, 2014
  
  
• Multiway dual Cheeger constant and spectral clustering of graphs
  Forschungsseminar Diskrete Geometrie, TU Chemnitz, Germany, July 15, 2014
  
  
• Cheeger constant, spectral clustering and eigenvalue ratios of Laplacian
  Oberseminar Analysis, Geometrie und Stochastik, Friedrich-Schiller-Universit?t Jena, Germany, July 9, 2014
  
  
• Cheeger constant, spectral clustering and eigenvalue ratios of Laplacian
  Oberseminar GEOMETRIE, MPI MiS, Leipzig, Germany, June 23, 2014
  
  

2013

• Kendall-type theorem for generalized harmonic maps
  Geometry and Topology Seminar, Durham University, November 21, 2013
  
  
• Ricci curvature and spectra estimates on graphs (slides, video)
  LMS-EPSRC Durham Symposium Graph theory and interactions, Durham University, July 16, 2013
  
  
• Eigenvalues and number of common neighbors of finite graphs
  Workshop 1 ZiF cooperation group "Discrete and Continuous Models in the Theory of Networks",
  ZiF, University of Bielefeld, Germany, June 26, 2013
  
  

2012

• Ricci curvature, local clustering and spectrum of finite graphs
  Strukturtheorie-Seminar, Department of Mathematical Structure Theory, TU Graz, Austria, September 18, 2012
  
  
• Harmonic functions on infinite semiplanar graphs
  Conference on Applications of Graph Spectra in Computer Science, CRM, Bellaterra (Barcelona), Spain, July 16-20, 2012
  
  
• Ollivier's Ricci curvature and neighborhood graphs
  Arbeitsgruppenseminar Sturm, Institut für Angewandte Mathematik, Universität Bonn, Germany, June 27, 2012
  
  
• Infinite semiplanar graphs with nonnegative combinatorial curvature
  Symposia, School of Mathematics and Statistics, Wuhan University, China, March 17, 2012
  
  

2011

• Ollivier-Ricci curvature on neighborhood graphs
  Oberseminar Analysis, Geometrie und Stochastik, Friedrich-Schiller-Universität Jena, Germany, November 16, 2011
  
  
• Ricci curvature and local clustering of graphs (slides)
  Graduate student symposium within the International Summer School on "Graphs and Spectra", TU Chemnitz, Germany, July 18-23, 2011
  
  
• Curvature, random walks, and the spectrum of the graph Laplace operator (jointly with Dr. Frank Bauer)
  Spring Scool on Limits of finite graphs, Leipzig, Germany, April 26-30, 2011
  
  

2009

• Reading seminar talk Formal Riemannian structure for space of probabiliy measures, its sectional curvature
  Arbeitsgmeinschaft: Optimal Transport and Geometry, MFO, Oberwolfach, Germany, March 29-April 4, 2009
  
  

Poster Presentation

• Multi-way dual Cheeger constants and hostile spectral clustering (pdf)
  Electrical Flows, Graph Laplacians, and Algorithms: Spectral Graph Theory and Beyond, ICERM, Brown University, April 7-11, 2014