Talks
Upcoming talks, minisymposia, and conferences
 Support Vector Machines and Radon's Theorem, Special Session on Computational Topology and Applications, AMS Western Sectional Meeting, online, May 15, 2022. See also this schedule. [Abstract, Slides, Slides as Notability file]
 GromovHausdorff distances, BorsukUlam theorems, and VietorisRips complexes, 3rd Biennial Meeting of SIAM Pacific Northwest Section, Washington State University, online talk, May 2022, 2022. [Abstract, Slides, Slides as Notability file]
 The unreasonably effective interaction between math and applications: A case study on persistence images, Sorbonne Université, Paris, France, June 9, 2022. [Abstract, Slides, Slides as Notability file]
 An introduction to applied topology, The Euler Circle, Palo Alto, CA, online, June 16, 2022. [Abstract, Slides]
 Applied, Combinatorial and Toric Topology, Institute for Mathematical Sciences, Singapore, online, July 1822, 2022.
 Algebraic Topology and Topological Data Analysis: A conference in honor of Gunnar Carlsson, Institute for Mathematics and its Applications, Minneapolis, MN, Aug 15, 2022.
Research talks
 GromovHausdorff distances, BorsukUlam theorems, and VietorisRips complexes, TU Graz, Austria, May 2022. [Abstract, Slides, Slides as Notability file]
 Topology in Machine Learning, Seminar on TDA and its applications, NTU Singapore, online, May 2022. [Abstract, Slides, Slides as Notability file]
 Bounding GromovHausdorff distances with BorsukUlam theorems and VietorisRips complexes, Oklahoma University Topology and Data Science Seminar, online, Apr 2022. [Abstract, Slides, Slides as Notability file, Video]
 GromovHausdorff distances, BorsukUlam theorems, and VietorisRips complexes, EPFL Applied Topology Seminar, Lausanne, Switzerland, online, Mar 2022. [Abstract, Slides, Slides as Notability file, Video]
 An introduction to VietorisRips complexes, Bilkent Topology Seminar, Turkey, online, Mar 2022. [Abstract, Slides, Slides as Notability file, Video]
 The topology of projective codes, Codes and Expansions (CodEx) Seminar, online, Feb 2022. [Abstract, Slides, Slides as Notability file, Video]
 Topology in machine learning, IST Austria Institute Colloquium, Jan 2022. [Abstract, Slides, Slides as Notability file]
 Bounding GromovHausdorff distances with BorsukUlam theorems and VietorisRips complexes, CopenhagenJerusalem Combinatorics Seminar, Copenhagen, Denmark, Dec 2021. [Abstract, Slides, Slides as Notability file, Video]
 Open questions on clique complexes of graphs, Facets of Complexity, Freie Universität Berlin, Technische Universität Berlin, and HumboldtUniversität zu Berlin, Germany, Nov 2021. [Abstract, Slides, Slides as Notability file]
 GromovHausdorff distances, BorsukUlam theorems, and VietorisRips complexes, Discrete Geometry and Topological Combinatorics research seminar, Freie Universität, Berlin, Germany, Nov 2021. [Abstract, Slides, Slides as Notability file]
 Open problems in need of computer simulation, Computational Persistence Workshop, online, Nov 2021. [Abstract, Slides, Slides as Notability file]
 The unreasonably effective interaction between pure and applied mathematics: A case study on persistence images, Workshop on Topology, Algebra and Geometry in Computer Vision at ICCV 2021, online, Oct 2021. [Abstract, Slides, Slides as Notability file]
 VietorisRips thickenings of spheres, Geometry Seminar, Pennsylvania State University, online, Oct 2021. [Abstract, Slides, Slides as Notability file]
 Relationships between persistent homology, machine learning, and local geometry, MiniConference on Computational Topology and Machine Learning for the Einstein Semester on Geometric and Topological Structure of Materials, online, Sept 2021. [Abstract, Slides, Slides as Notability file]
 VietorisRips thickenings of spheres, Algebraic Geometry and Geometric Topology Seminar, Tulane University, online, Sept 2021. [Abstract, Slides, Slides as Notability file]
 VietorisRips complexes of hypercube graphs, Workshop on Beyond TDA  Persistent functions and its applications in data sciences, online, Aug 2021. [Abstract, Slides, Slides as Notability file, Video]
 Applied topology: From global to local, DANGER workshop focused on applications of machine learning to pure mathematics, online, Aug 2021. [Abstract, Slides, Slides as Notability file, Video]
 Topology in Machine Learning, Workshop on Knowledge Guided Machine Learning (KGML), online, Aug 2021. [Abstract, Slides, Slides as Notability file, Video]
 The unreasonably effective interaction between pure and applied mathematics: A case study on persistence images, CIMAT/TRIPODS 2021 Summer Conference, online, Aug 2021. [Abstract, Slides, Slides as Notability file]
 Bridging applied and geometric topology, 38th Annual Workshop in Geometric Topology, online, June 2021. [Abstract, Slides, Slides as Notability file, Video]
 The unreasonably effective interaction between pure and applied mathematics: A case study on persistence images, Minisymposium on Topological Signal Processing at the SIAM conference on Applications of Dynamical Systems, online, May 2021. [Abstract, Slides, Slides as Notability file]
 Representations of energy landscapes by sublevelset persistent homology: An example with nalkanes, Minisymposium on MultiScale Statistical Descriptors of Materials at the SIAM Conference on Mathematics Aspects of Materials Science, online, May 2021. [Abstract, Slides, Slides as Notability file]
 Twotalk workshop on Topology in Data Science at The 54th Spring Topology and Dynamical Systems Conference, online, May 2021. [Abstract, Slides Part I, Slides Part II]
 Bridging applied and quantitative topology at a Virtual Workshop on Topological Data Analysis: Theory and Applications, hosted by the University of Western Ontario and the Tutte Institute, May 2021. [Abstract, Slides, Slides as Notability file]
 Representations of energy landscapes by sublevelset persistent homology: An example with nalkanes, American Chemical Society symposium on Graph theory underpinning new domains of physical chemistry, online, Apr 2021. [Abstract, Slides, Slides as Notability file]
 VietorisRips thickenings: Problems for birds and frogs, VietorisRips Seminar, online, Mar 2021. [Abstract, Slides, Slides as Notability file, Video]
 Minicourse on A visual introduction to geometric data analysis with Lara Kassab at the workshop Geometry: Education, Art, and Research, online, Banff International Research Station, Feb 1921, 2021. [Slides, Slides as Notability file, Video Part 1, Video Part 2]
 Descriptors of Energy Landscapes using Topological Analysis (DELTA) at the AMS Special Session on Combinatorial Approaches to Topological Structures and Applications, Joint Mathematics Meetings, Washington DC, online, Jan 2021. [Abstract, Slides, Slides as Notability file]
 Applied topology: From global to local at the AMS Special Session on Geometry in the Mathematics of Data Science, Joint Mathematics Meetings, Washington DC, online, Jan 2021. [Abstract, Slides, Slides as Notability file]
 Bridging applied and quantitative topology at the Topology and Dynamics Seminar, University of Florida, Gainesville, online, Oct 2020. [Abstract, Slides, Slides with blanks]
 Metric reconstruction via optimal transport, Workshop on Optimal Transport, Topological Data Analysis, and Applications to Shape and Machine Learning, Mathematical Biosciences Institute  The Ohio State University, online conference, July 2020. [Abstract, Slides, Slides with blanks, Video]
 BorsukUlam theorems and VietorisRips complexes, Workshop on Topological Data Analysis, as part of the Thematic Program on Toric Topology and Polyhedral Products, Fields Institute, Toronto, Canada, online conference, June 2020. [Abstract, Slides, Slides with blanks, Video]
 Descriptors of Energy Landscapes using Topological Analysis (DELTA) at the Mathematics of Data Science Virtual Lecture Series, Tufts University, June 2020. [Abstract, Slides, Slides as Notability file, Video]
 Applied topology: From global to local at the Mathematics of Data and Decisions at Davis (MADDD) Seminar, UC Davis, online talk, June 2020. [Abstract, Slides, Slides as Notability file, Video]
 From persistent homology to machine learning, for the Minisymposium on Topological Image Analysis of the SIAM Conference on Mathematics of Data Science (MDS20). This event was rescheduled virtually for June, 2020. [Abstract, Slides, Video, Conference Poster]
 VietorisRips complexes and BorsukUlam theorems, Online Algebraic Topology Seminar (OATS), May 2020. [Abstract, Slides, Video]
 Computational topology and energy landscapes, National Meeting of the American Chemical Society, for the Graph Theory Underpinning New Domains of Physical Chemistry symposium, Philadelphia, PA, Mar 2020. Talk changed to an online slide submission due to COVID19. [Abstract, Slides as PDF, Slides on conference webpage]
 Gave a minicourse on Geometric complexes in applied topology at the Winter School on Geometric and Topological Data Analysis at CIMAT, in Guanajuato, Mexico, Jan 2020. [Abstract, Notes]
 VietorisRips thickenings of spheres. AMS Special Session on VietorisBorsukRips Homotopy, Joint Mathematics Meetings, Denver, Jan 2020. [Abstract, Slides]

Metric reconstruction via optimal transport.
[Abstract,
Slides,
Notes]
 Arches Topology Conference, Hurricane, Utah, Apr 2019.
 AMS Special Session on Topological Data Analysis: Theory and Applications, Joint Mathematics Meetings, Baltimore, Jan 2019. [Slides with an application to BorsukUlam theorems]
 Topology Seminar, Texas State University, Nov 2018. [Abstract]
 Upstate New York Topology Seminar (UNYTS), University of Albany, Nov 2018. [Notes]
 LafayetteLehigh GeometryTopology Seminar, Apr 2018. [Notes]
 AATRN Online Seminar, Oct 2017. [Video]
 58th Cascade Topology Seminar, University of British Columbia, May 2017.
 Florida International University Winter Conference on Geometry, Topology, and Applications, Jan 2017. [Abstract, Old Notes]

An introduction to applied topology.
[Abstract]
 Applied Mathematics Colloquium, CU Boulder, Sept 2019. [Abstract, Slides]
 Three talk lecture series, along with a software tutorial on persistent homology, at the Summer School on Data Science for Dynamical Systems, Lorentz Center, Leiden University, Netherlands, July 2019. [Slides]
 The Symposium of Physics and Mathematics FCFMIFM at the University of Michoacan, Morelia, Mexico, Nov 2018. [Abstract, Slides]
 Department Colloquium, Texas State University, Nov 2018. [Abstract, Slides]
 Data Science Seminar, University of Tennessee, Nov 2018. [Slides]
 Undergraduate colloquium at Lafayette College, Apr 2018. [Abstract, Slides]
 Florida International University Winter Conference on Geometry, Topology, and Applications, Jan 2017. [Abstract, Slides]
 CSU Computer Science Colloquium, Oct 2016. [Abstract, Slides, Video]
 An introduction to applied topology software. NSFCBMS Conference and Software Day on Topological Methods in Machine Learning and Artificial Intelligence, College of Charleston, South Carolina, May 2019. Also led a weeklong research conversation group, and an afternoonlong coding sprint on reallife applied topology examples for beginners. [Abstract, Slides, Video]
 Survey: From persistent homology to machine learning feature vectors. TRIPODS Summer Bootcamp on Topology and Machine Learning, ICERM, Aug 2018. [Abstract, Slides]
 Connections between Čech complexes and Carathéodory orbitopes. Special Session on Algebraic, Geometric, and Topological Methods in Combinatorics at the AMS Sectional Meeting, Northeastern University, Boston, Apr 2018. [Slides]

The theory of VietorisRips complexes.
 AMS Special Session on Topological Data Analysis, Joint Mathematics Meetings in San Diego, Jan 2018. [Abstract, Slides]
 Applied Topology Seminar, Brown University, Mar 2017. [Abstract, Notes]
 Minisymposium on Applied and Computational Topology at the SIAM Central States Section Meeting, Oct 2016. [Slides]

VietorisRips complexes of circles, ellipses, and higherdimensional spheres.
 Topology, Geometry, and Data Analysis seminar at The Ohio State University, Feb 2017. [Abstract, Notes]
 Joint Mathematics Meetings, AMS Special Session on Applied and Computational Topology, Jan 2016. [Abstract, Slides]
 What is topology, and how is it applied to data analysis? Front Range Computational & Systems Biology Symposium, July 2016.

The VietorisRips complexes of a circle.
[Abstract,
Slides,
Poster]
 University of Rochester Data Science Colloquium, Apr 2015.
 Applied Algebraic Topology Research Network, Online Seminar Series, Mar 2015. [Video]
 Colloquium at Colorado State University, Jan 2015.
 Geometry and Topology Seminar at Tulane University, Nov 2014.
 Applied Topology Seminar at the University of Pennsylvania, Nov 2014.
 Graduate and Faculty Seminar at Duke University, Oct 2014.
 Colloquium at UNC Greensboro, Oct 2014.
 Geometry and Topology Seminar at North Carolina State University, Sept 2014.
 IMA Postdoc Seminar, May 2014.
 IMA Postdoc Seminar, Oct 2013.

Evasion paths in mobile sensor networks.
[Abstract,
Slides,
SlidesForUndergrads,
Poster,
Multimedia]
 AMS Special Session on Applied Topology, Joint Mathematics Meetings, online, Jan 2021. [Abstract, Slides]
 Williams College Colloquium, Mar 2018.
 Topological data analysis of exclusion zones, Edinburgh, Scotland, Dec 2017.
 CSU Pattern Analysis Lab, Oct 2015.
 Duke Graduate & Faculty Seminar, Feb 2015.
 IMA Workshop on Topological Systems: Communication, Sensing, and Actuation, Mar 2014. [Video]
 Rocky Mountain Algebraic Combinatorics Seminar, Nov 2013.
 SIAM Conference on Applied Algebraic Geometry, Aug 2013.
 Applied Topology in Będlewo, July 2013.
 MSRI Workshop on Algebraic Topology, June 2013. [Video]
 Ayasdi Topology Day, June 2013.
 Stanford CompTop Seminar, May 2013.
 Special Session on Applied and Computational Topology at MAA MathFest, Aug 2012.
 Algebraic Topology: Applications and New Directions, July 2012.
 Minisymposium on Applied Algebraic Topology at SIAM Annual Meetings, July 2012. [Video]
 Schloss Dagstuhl Seminar on Applications of Combinatorial Topology to Computer Science, Mar 2012.
 AMS Special Session on Computational and Applied Topology, Joint Meetings, Jan 2012.
 SIAM Conference on Applied Algebraic Geometry, Oct 2011.

Nudged elastic band in topological data analysis.
[Abstract]
 SIAM Conference on Applied Algebraic Geometry, Oct 2011. [Slides]
 Stanford CompTop Seminar, Jan 2010. [Slides]
 AMSSIAM Special Session on Applications of Algebraic Geometry, Joint Meetings, Jan 2010.
 Topological data analysis: Understanding optical flow. IMA Short Course on Applied Algebraic Topology, June 2009. [Slides]
Software talks and demonstrations
 Introduction to Javaplex software for persistent homology. [Abstract]
 Introduction to JPlex software for persistent homology.
Departmental talks and Expository talks
 An introduction to cyclic polytopes, BarvinokNovik orbitopes, and the sparsitypromoting L^{1} norm, VietorisRips  Tight Span Joint CSUOSU Seminar, online, June 2021.
 What could Math+YouTube become?, for the CSU Math Department Who is ... what is ...? seminar, online, Mar 2021. [Abstract, Slides, Video]
 Coffee break chat on data science, Data Science Seminar, Colorado State University, online, Jan 2021.
 Fair Division, for the Data Science Seminar, Colorado State University, Sept 2020. [Abstract, Notes, Video]
 BorsukUlam theorems into higherdimensional codomains, for the Rocky Mountain Algebraic Combinatorics Seminar, May 2020. [Abstract, Slides, Slides with blanks, Video]
 Applying for jobs after math graduate school, Student Chapter of the AMS at CSU, Apr 2020. [Abstract]
 Persistent homology, zigzag persistence, and quiver representations, CSU Topology Seminar, Feb 2020. [Abstract]
 Neighborly polytopes and the sparsitypromoting L^{1} norm, CSU Data Science Seminar, Feb 2020. [Abstract, Notes]
 An introduction to persistent homology. Descriptors of Energy Landscape by Topological Analysis (DELTA), Online Seminar, Jan 2020. [Abstract, Slides, Video]
 An introduction to applied topology. CSU DSCI 100: First Year Seminar in Data Science, Nov 2019. [Slides]
 An introduction to Morse theory. Descriptors of Energy Landscape by Topological Analysis (DELTA), Online Seminar, Nov 2019. [Abstract, Video]
 An introduction to applied topology. CSU Data Science Seminar, Oct 2019. [Slides]
 An introduction to matroids. CSU Topology Seminar, Sept 2019. [Notes]
 Applying to academic jobs. CSU Math Department, Sept 2019.
 An introduction to applied topology. Talk for an REU at CU Boulder, June 2019. [Slides]
 The waist inequality. CSU Topology Seminar, Mar 2019. [Notes/Slides, Reference]
 An introduction to applied topology. CSU DSCI 100: First Year Seminar in Data Science, Dec 2018. [Slides]
 Lovász' proof of the Kneser conjecture. CSU Topology Seminar, Nov 2018.
 Using homotopy colimits to understand infinite simplicial complexes. CSU Topology Seminar, May 2018. [Abstract, Notes]
 An introduction to homotopy colimits. CSU Topology Seminar, Apr 2018. [Abstract, Notes]
 VietorisRips complexes of the circle. CSU Topology Seminar, Oct 2017.
 Sperner's lemma and fair division. CSU Math Club, Oct 2017. [Abstract, Notes]
 An introduction to VietorisRips complexes. CSU Topology Seminar, Sept 2017.
 Cyclic polytopes and nerve complexes. Rocky Mountain Algebraic Combinatorics Seminar, Oct 2016. [Abstract, Notes]
 Random cyclic dynamical systems. Rocky Mountain Algebraic Combinatorics Seminar, Sept 2015. [Abstract]
 Introduction to discrete Morse theory. University of Minnesota Student Topology Seminar, Dec 2013. [Notes]
 Applied topology. Stanford University Mathematics Camp Guest Lecture Series, July 2013. [Slides]
 Applied topology. Stanford University Mathematics Camp Guest Lecture Series, July 2011.
 Coverage problems in sensor networks. Stanford Undergraduate Mathematical Organization Speaker Series, May 2010. [Abstract]
Talks for undergraduate students
It's important that mathematicians target some of our talks at a level appropriate for undergraduate audiences. This is perhaps especially true in applied topology, since it is an attractive area for introducing students to research. The slides for two talks that I like to give for undergraduates, in which I try to focus on pictures and deemphasize formulas, are available here and here.Conferences organized
 With Johnathan Bush, Sunhyuk Lim, Facundo Mémoli, coorganized the Bridging applied and quantitative topology workshop, online, May 913, 2022.
 With Maria D'Orsogna, Rachel Neville, Jose Perea, and Chad Topaz, coorganized an ICERM Topical Workshop on Applied mathematical modeling with topological techniques, Aug 59, 2019. [Poster]
 With Jeffrey Brock, Melissa McGuirl, Bjorn Sandstede, and Yitzchak Solomon, coorganized an ICERM TRIPODS Summer Bootcamp on Topology and Machine Learning, Aug 610, 2018. Software tutorial available. [Photo]
Minisymposia organized
 With Sara Kalisnik and Elchanan Solomon, coorganizing the AATRN Interview Series, online, 2020present.
 With Facundo Mémoli, coorganizing the AATRN VietorisRips Seminar, online, 2021present.
 With Justin O'Connor, Brittany Story, Kyle Salois, and Ciera Street, coorganized an AMS Special Session on Presenting Research Mathematics Through Visual Storytelling: Slides Without Words and Equations, Joint Mathematics Meetings, online, Apr 2022.
 With Hana Dal Poz Kouřimská, Teresa Heiss, and Antonio Rieser, coorganized the inaugural AATRN Poster Session, online, Oct 2021.
 With Hana Dal Poz Kouřimská, Teresa Heiss, Sarah Percival, Lori Ziegelmeier, coorganized the inaugural AATRN+WinCompTop Tutorialathons, online, Mar 2021 and Nov 2021.
 With Mikael VejdemoJohansson, coorganized an AMS Special Session on Applied Topology, Joint Mathematics Meetings, Denver, CO, Jan 17, 2020.
 With Mehmet Aktas, Wenwen Li, Murad Ozaydin, coorganized a minisymposium on Applied and Computational Topology at the SIAM Central States Section Meeting, University of Oklahoma, Oct 57, 2018
 With Ellen Gasparovic and Katharine Turner, coorganized the 7th Annual Minisymposium on Computational Topology at Computational Geometry Week, Budapest, June 2018.
 With Mikael VejdemoJohansson, coorganized an AMS Special Session on Topological Data Analysis at the Joint Mathematics Meetings in San Diego, Jan 2018.
 With Florian Frick, coorganized a session on Symmetric Simplicial Complexes and Polytopes at the SIAM Conference on Applied Algebraic Geometry, Georgia Institute of Technology, JulAug 2017.
 With Bala Krishnamoorthy, coorganized a session on Recent Advances in Applied Algebraic Topology at the AMS Western Sectional Meeting, Washington State University, Apr 2017.
 With Patrick Shipman, coorganized a minisymposium on Applied and Computational Topology at the SIAM Central States Section Meeting, University of Arkansas at Little Rock, Oct 2016.
Conference program committees
 Spring Topology and Dynamical Systems Conferences, Steering Committee Member, 20222025.
 Symposium on Computational Geometry (SoCG), Program Committee Member, Berlin, Germany, June 2022.
 Symposium on Computational Geometry (SoCG), Multimedia Exposition Track Committee Member, Zürich, Switzerland, June 2020.
 Program committee member for the IEEE ICMLA Special Session on Topological Data Analysis in Machine Learning, Boca Raton, Florida, Dec 2019.
Panels
 Panelist for the Virtual Department of Energy (DOE) Basic Energy Sciences (BES) Chemical Sciences, Geosciences, and Biosciences (CGSB) Data Science Workshop. On Panel 3: Understanding Topology of Chemical Data, Sept 2020.
 Panelist for Next Steps: Mathematics Departments and the Explosive Growth of Computational and Quantitative Offerings in Higher Education, AMS Committee on Education Panel, Joint Mathematics Meetings, Denver, CO, Jan 2020.
YouTube tutorials
I sometimes make YouTube tutorials, such as the following.What is the difference between VietorisRips and Čech complexes?
(See Section VI at my research page to download this Mathematica demo.)
Paper introduction: "Computing persistent homology" by Afra Zomorodian and Gunnar Carlsson [Notes, Notes with blanks]
Poster presentations
 Metric reconstruction via optimal transport. SIAM Conference on Applied Algebraic Geometry, July 2017. [Poster]
 The VietorisRips complexes of a circle. ICERM Workshop on Topology and Geometry in a Discrete Setting, Nov 2016. [Poster]
 The VietorisRips complex of the circle. IMA Workshop on Topology and Geometry of Networks and Discrete Metric Spaces, Apr 2014. [Poster]
 VietorisRips and restricted Čech complexes of circular points. IMA Workshop on Topological Systems: Communication, Sensing, and Actuation, Mar 2014. [Poster]
 Evasion paths in mobile sensor networks. [Poster]
 Mobile sensors and pursuitevasion: Can directed algebraic toplogy help? Aalborg GETCO Workshop, Jan 2010. [Poster]