Research Interests

Analysis and applications

  1. Inverse problems

    • One-dimensional scattering in non-smooth media
    • Acoustic imaging
    • Computational methods
  2. Orthogonal polynomials
  3. Combinatorial and differential geometry
  4. Complex analysis



  • Theorems of Szegö-Verblunsky type in the multivariate and almost periodic settings, 32 pages, 2022 [ArXiv version]


  • Scattering on the line via singular approximation, 87 pages, 2021 [ArXiv version]

Recent Publications


  • with Sophia Bugarija, Peijun Li, Guanghui Hu and Yue Zhao, Inverse scattering for the one-dimensional Helmholtz equation with piecewise constant wave speed, Inverse Problems 36 (2020), no. 7, 075008, 16pp.
    [journal link]


  • Disk polynomials and the one-dimensional wave equation, Journal of Approximation Theory 244 (2019) 37-56. [journal link]


  • Acoustic imaging of layered media, Journal of Computational Physics 372 (2018) 524-545. [journal link]
  • The refined impedance transform for 1D acoustic reflection data, Inverse Problems 34 (2018), no. 7, 075013, 14pp. [journal link]
  • with Guanghui Hu and Yue Zhao, Inverse medium scattering from periodic structures with fixed-direction incoming waves, Inverse Problems 34 (2018), no. 7, 075011, 18pp.
    [journal link]
  • A scattering-based algorithm for wave propagation in one dimension, Numer. Methods Partial Differential Equations, 34 (2018), no. 2, 442-450. [journal link] [ArXiv version]


  • Fourier expansion of disk automorphisms via scattering in layered media, J. Fourier Anal. Appl. 23 (2017), no. 6, 1495-1516. [journal link]
    [ArXiv version].
  • with Larry Bates, A geometry where everything is better than nice, Proc. Amer. Math. Soc. 145 (2017), no. 1, 461-465. [journal link] [ArXiv version]

    Geodesics of the scattering metric are generated by hinged circles rolling in a bigger circle.

  • On the measurement operator for scattering in layered media, Inverse Problems and Imaging 11 (2017), no. 1, 87-97. [journal link]


  • The Pólya-Schur problem on the unit circle, C. R. Math. Acad. Sci. Soc. R. Can. 37 (2015), no. 4, 131-141. MSC 30C15 (47B38). [journal link]
  • with Michael Lamoureux, Constructive solutions to Pólya-Schur problems, J. Funct. Anal. 269 (2015), no. 10, 3264-3281. MSC 47B33 (30C10 30C15 30H10). [ArXiv version]
  • with M. S. Tavalla, The structure of test functions that determine weighted composition operators, Sampling Theory and Applications (SampTA), 2015 International Conference on, Washington, DC, 2015, pp. 201-205. [IEEE Xplore link], [ArXiv version]


  • The combinatorics of scattering in layered media, SIAM J. Appl. Math. 74 (2014), no. 4, 919-938. MSC 74J25 (35A08 35P25 35R30 76Q05 86A15). [ArXiv version]
  • A multivariate interpolation problem arising from the scattering of waves in
    layered media, Dolomites Res. Notes Approx. DRNA, 7:7-15, 2014. [journal link]

Conferences and scholarly presentations

  • Mathematics Colloquium, University of Louisiana Lafayette, USA, March 17, 2022
  • Invited speaker, Fraunhofer Institute IKTS, Dresden, Germany, March 3, 2021
  • Invited speaker, Minisymposium on Recent Developments on Inverse Scattering: Theory and Computation, AIP 2019, Grenoble, France, July 8-13, 2019 [web site]
  • Organizer, Minisymposium on Inverse Problems in Industry, CAIMS Annual Meeting 2019, Whistler, BC, June 9-13, 2019 [web site]
  • Main organizer, Session on Inverse Problems in Mathematical Physics, CMS Winter Meeting, Vancouver, December 7-10, 2018 [web site]
  • Co-organizer, Inverse Problems and Image Analysis Seminar, Fields Institute, Toronto, ongoing [web site]
  • Fields Undergraduate Summer Research Program, Fields Institute, Toronto, July 4-August 31, 2017 [web site]
  • Geophysical Simulation and Inversion, BIRS Workshop 16w2695, Banff, August 19-21, 2016 [web site]
  • Imaging methods in coupled physics models, The 11th AIMS Conference on Dynamical Systems,
    Differential Equations and Applications
    , Orlando, Florida, July 1-5, 2016 [web site]
  • Co-organizer (with Michael Haslam): Recent Advances in Algorithms for Scattering and Inverse Problems, The 10th International Conference on Scientific Computing and Applications, The Fields Institute, Toronto, June 6-10, 2016 [web site]