• Computing the Interleaving Distance is NP-Hard 

      Bjerkevik, Håvard Bakke; Botnan, Magnus Bakke; Kerber, Michael (Journal article; Peer reviewed, 2019)
      We show that computing the interleaving distance between two multi-graded persistence modules is NP-hard. More precisely, we show that deciding whether two modules are 1-interleaved is NP-complete, already for bigraded, ...
    • Continuity of Formal Power Series Products in Nonlinear Control Theory 

      Gray, W. Steven; Palmstrøm, Mathias; Schmeding, Alexander (Peer reviewed; Journal article, 2022)
      Formal power series products appear in nonlinear control theory when systems modeled by Chen–Fliess series are interconnected to form new systems. In fields like adaptive control and learning systems, the coefficients of ...
    • On Numerical Approximations of Fractional and Nonlocal Mean Field Games 

      Chowdhury, Indranil; Ersland, Olav; Jakobsen, Espen Robstad (Peer reviewed; Journal article, 2022)
      We construct numerical approximations for Mean Field Games with fractional or nonlocal diffusions. The schemes are based on semi-Lagrangian approximations of the underlying control problems/games along with dual approximations ...