Ruoyuan Liu


E-mail: ruoyuan.liu (at) ed (dot) ac (dot) uk




Mailing Address:
School of Mathematics
The University of Edinburgh
James Clerk Maxwell Building
The King's Buildings, Peter Guthrie Tait Road
Edinburgh, EH9 3FD, United Kingdom

    Please see my new webpage here.


    Research Interests:

    Nonlinear partial differential equations and (singular) stochastic PDEs. In particular, study of (deterministic and probabilistic) nonlinear dispersive PDEs, using the techniques from PDEs, harmonic analysis, and probability.





    Papers:

    1. (with A. Chapouto and G. Li) Global dynamics for the stochastic nonlinear beam equations on the four-dimensional torus, submitted (2023). arXiv link.
    2. (with E. Brun, G. Li, and Y. Zine) Global well-posedness of one-dimensional fractional cubic nonlinear Schrödinger equations in negative Sobolev spaces, submitted (2023). arXiv link.
    3. (with N. Tzvetkov and Y. Wang) Existence, uniqueness, and universality of global dynamics for the fractional hyperbolic Φ43-model, submitted (2023). arXiv link.
    4. (with E. Brun and G. Li) Global well-posedness of the energy-critical stochastic nonlinear wave equations, J. Differential Equations 397 (2024), 316-348. arXiv link.
    5. (with A. Debussche, N. Tzvetkov, and N. Visciglia) Global well-posedness of the 2D nonlinear Schrödinger equation with multiplicative spatial white noise on the full space, Probab. Theory Related Fields 189 (2024), no. 3-4, 1161-1218. arXiv link
    6. (with T. Oh) Sharp local well-posedness of the two-dimensional periodic nonlinear Schrödinger equation with a quadratic nonlinearity |u|2, to appear in Math. Res. Lett. arXiv link
    7. Local well-posedness of the periodic nonlinear Schrödinger equation with a quadratic nonlinearity u2 in negative Sobolev spaces, to appear in J. Dyn. Diff. Equat. arXiv link
    8. Global well-posedness of the two-dimensional stochastic viscous nonlinear wave equations, Stoch. Partial Differ. Equ. Anal. Comput. 12 (2024), no. 2, 898-931. arXiv link
    9. On the probabilistic well-posedness of the two-dimensional periodic nonlinear Schrödinger equation with the quadratic nonlinearity |u|2, J. Math. Pures Appl. 171 (2023), 75-101. arXiv link
    10. (with T. Oh) On the two-dimensional singular stochastic viscous nonlinear wave equations, C. R. Math. Acad. Sci. Paris 360 (2022), 1227-1248. arXiv link
    11. (with G. Chasapis and T. Tkocz) Rademacher-Gaussian tail comparison for complex coefficients and related problems, Proc. Amer. Math. Soc. 150 (2022), no. 3, 1339-1349. arXiv link
    12. (with T. Tkocz) A note on the extremal non-central sections of the cross-polytope, Adv. in Appl. Math. 118 (2020), 102031, 17pp. arXiv link


    Notes:

    • Invariant Gibbs measures for the three dimensional cubic nonlinear wave equation, Edinburgh, Fall 2022. Notes





    The University of Edinburgh, UK

    • Tutor for "Honours Analysis", Fall 2023
    • Tutor for "Calculus and its Applications", Spring 2023
    • Tutor for "Honours Complex Variables - Skills", Spring 2023
    • Tutor for "Honours Analysis", Fall 2022
    • Tutor for "Honours Analysis - Skills", Fall 2022
    • Tutor for "Maths Base Semester 1", Fall 2022
    • Tutor for "Fundamentals of Pure Mathematics", Spring 2022
    • Tutor for "Maths Base Semester 2", Spring 2022

    Carnegie Mellon University, US

    • Teaching assistant for "Multidimensional Calculus", Spring 2020
    • Teaching assistant for "Concepts of Mathematics", Spring 2018
    • Teaching assistant for "Differential and Integral Calculus", Fall 2017




    Education:

    • Sep. 2021 - present
      • Ph.D. candidate, The University of Edinburgh, Edinburgh, UK
    • Jan. 2019 - May 2020
      • M.S. in Mathematical Science, Carnegie Mellon University, Pittsburgh, PA, US
    • Sep. 2016 - May 2020
      • B.S. in Mathematical Science (with University Honors and College Honors), Carnegie Mellon University, Pittsburgh, PA, US
    • Sep. 2016 - May 2020
      • B.S. in Computer Science (with University Honors), Carnegie Mellon University, Pittsburgh, PA, US

    Awards:

    The University of Edinburgh, UK
    • Aug. 2023
      • Sir William Darling Memorial Prize 2023 (a university-wide prize for pre-eminence in sport and academia)
    • Mar. 2023
      • Laura Wisewell travel fund




    Besides mathematics, I like playing billiards games, especially snooker. I play competitively as an amateur player. Below are some of my achievements.

    Snooker

    American pool

    • 9th place and winner of Men's Sportsmanship Award, ACUI Collegiate 9-Ball National Championships, Champaign, IL, US, Jun. 2019.
    • 7th place, ACUI Collegiate 9-Ball National Championships, West Lafayette, IN, US, Jun. 2018.