Thi Xuan Vu

Brief Bio

Since September 2024, I have been an Associate Professor (Maître de Conférences) at the Université de Lille, working in the CRIStAL laboratory as part of the CFHP team.

In December 2020, I obtained my PhDs in Computer Science under a cotutelle from the University of Waterloo, Canada (supervised by Éric Schost and George Labahn) and Sorbonne University, France (supervised by Mohab Safey El Din). After my doctorate, I was a postdoctoral researcher at UiT The Arctic University of Norway until February 2024, working with Cordian Riener, and spent six months at Johannes Kepler University in Linz, Austria, collaborating with Manuel Kauers.

Research

My research interests lie in symbolic computation (computer algebra), computational (real) algebraic geometry, and polynomial system solving.

Preprints

1. The DenefLipshitz Algorithm: Deciding the Existence of Formal Power Series Solutions in Differential Algebra (2025)
   François Boulier, François Lemaire, and Thi Xuan Vu
   HAL
2. Symbolic Computation with Symmetric Polynomials in Real Algebraic Geometry (2025)
   Cordian Riener and Thi Xuan Vu
   arXiv / HAL

Publications

1. Deciding Connectivity in Symmetric Semi-Algebraic Sets
   Cordian Riener, Robin Schabert, and Thi Xuan Vu
   Journal of Symbolic Computation, Volume 138 (2027), Special Issue for ISSAC 2024
   free-access (until August 26, 2026) / DOI / arXiv / HAL
2. A Symbolic Homotopy Algorithm for Solving Composable Polynomial Systems
   Thi Xuan Vu
   Proceedings of ISSAC 2026 (Oldenburg, Germany)
   DOI / arXiv / HAL
3. Computing Polynomial Representation in Subrings of Multivariate Polynomial Rings
   Thi Xuan Vu
   Proceedings of ISSAC 2025 (Guanajuato, Mexico)
   DOI / arXiv / HAL
4. Connectivity in Symmetric Semi-Algebraic Sets
   Cordian Riener, Robin Schabert, and Thi Xuan Vu
   Proceedings of ISSAC 2024 (Raleigh, NC, USA)
   DOI / arXiv
   Robin Schabert received a SIGSAM Distinguished Student Author Award for this paper.
5. Computing Critical Points for Invariant Algebraic Systems
   George Labahn, Mohab Safey El Din, Éric Schost, and Thi Xuan Vu
   Journal of Symbolic Computation, Volume 116 (2023)
   DOI / arXiv
6. Faster Real Root Decision Algorithm for Symmetric Polynomials
   George Labahn, Cordian Riener, Mohab Safey El Din, Éric Schost, and Thi Xuan Vu
   Proceedings of ISSAC 2023 (Tromsø, Norway)
   DOI / arXiv
7. Computing Critical Points for Algebraic Systems Defined by Hyperoctahedral Invariant Polynomials
   Thi Xuan Vu
   Proceedings of ISSAC 2022 (Lille, France)
   DOI / arXiv
8. Rank-sensitive Computation of the Rank Profile of a Polynomial Matrix
   George Labahn, Vincent Neiger, Thi Xuan Vu, and Wei Zhou
   Proceedings of ISSAC 2022 (Lille, France)
   DOI / arXiv
9. Homotopy Techniques for Solving Sparse Column Support Determinantal Polynomial Systems
   George Labahn, Mohab Safey El Din, Éric Schost, and Thi Xuan Vu
   Journal of Complexity, Volume 66 (2021)
   DOI / arXiv
10. Solving Determinantal Systems Using Homotopy Techniques
    Jonathan D. Hauenstein, Mohab Safey El Din, Éric Schost, and Thi Xuan Vu
    Journal of Symbolic Computation, Volume 104 (2021)
    DOI / arXiv
11. Computing Canonical Bases of Modules of Univariate Relations
    Vincent Neiger and Thi Xuan Vu
    Proceedings of ISSAC 2017 (Kaiserslautern, Germany)
    DOI / arXiv
    Received a SIGSAM Distinguished Student Author Award for this paper.

PhD Thesis

Teaching

I teach undergraduate and graduate courses in algorithms and programming at the Université de Lille.

• Fall 2026: Refresher in Computer Science (M2 Scientific Computing-CM); Algorithms and Complexity (M1 Computer Science-CM/TD/TP); Intro Research (M1 Computer Science-TDM); Cryptography (M1 Computer Science-CM/TD/TP);
• 2025-2026 (around 200h): Cryptologie (S6 Polytech Lille-CM/TD/TP); Bases de la Programmation en C (L2-TD/TP); Algorithmes et Programmation (L1-TD/TP); Refresher in Computer Science (M2 Scientific Computing-CM); ODI (L1-TDM); ACT (M1-TD/TP); IIR (M1-TDM)
• 2024-2025 (162h): ODI (L1-TDM); ACT (M1-TD/TP); IIR (M1-TDM); Bases de la Programmation en C (L2-TD/TP); Algorithmes et Programmation (L1-TD/TP)

During my doctorate at the University of Waterloo, I was a teaching assistant for the following courses: CS 466/666 (Algorithm Design and Analysis); CS 475/675 (Computational Linear Algebra); AMATH 242/CS 371 (Introduction to Computational Math); CS 245 (Logic and Computation); CS 136 (Elementary Algorithm Design and Data Abstraction).

Students

Internship

• 2025
  Alexis Evaristo

  1A Polytech Lille. Supervised with François Boulier.

Community Service

• 2026
  Proceedings Editor, ISSAC 2026, Oldenburg, Germany.
• 2026
  Publicity Chair, CASC 2026, Bath, UK.
• 2025
  Software Presentations Chair, ISSAC 2025, Guanajuato, Mexico.
• 2023
  Local Arrangements Committee, ISSAC 2023, Tromsø, Norway.

Talks

• Sept. 2026
  Symbolic Homotopy Techniques for Structured Multivariate Polynomial Systems

  CASC 2026, Bath, UK.
• 2026
  A Symbolic Homotopy Algorithm for Solving Composable Polynomial Systems

  ISSAC 2026, Oldenburg, Germany. ( slides )
• 2026
  On (De)composable Polynomial Systems

  Seminar at Pascaline team, LIP, ENS Lyon, France.
• 2026
  Computing Polynomial Representation in Subrings of Multivariate Polynomial Rings

  JNCF 2026 (Francophone Computer Algebra Days), CIRM, Luminy, France.
• 2025
  Computing Polynomial Representation in Subrings of Multivariate Polynomial Rings

  SCG Seminar, University of Waterloo, Canada.
• 2025
  Computing Polynomial Representation in Subrings of Multivariate Polynomial Rings

  ISSAC 2025, Guanajuato, Mexico.