• A Nonlinear Partial Differential Equation and Its Viscosity Solutions 

      Reigstad, Audun (Master thesis, 2016)
      We study a nonlinear partial differential equation with Lipschitz continuous coefficient functions. Existence and uniqueness of viscosity solutions is proved by approximating with minimizers of variational integrals. The ...
    • Competition models for plant stems 

      Bressan, Alberto; Galtung, Sondre Tesdal; Reigstad, Audun; Ridder, Johanna (Peer reviewed; Journal article, 2020)
      The models introduced in this paper describe a uniform distribution of plant stems competing for sunlight. The shape of each stem, and the density of leaves, are designed in order to maximize the captured sunlight, subject ...
    • A Regularized System for the Nonlinear Variational Wave Equation 

      Reigstad, Audun (Doctoral theses at NTNU;2021:21, Doctoral thesis, 2021)
    • Traveling waves for the nonlinear variational wave equation 

      Grunert, Katrin; Reigstad, Audun (Peer reviewed; Journal article, 2021)
      We study traveling wave solutions of the nonlinear variational wave equation. In particular, we show how to obtain global, bounded, weak traveling wave solutions from local, classical ones. The resulting waves consist of ...