ArXiv (open access)

Key ideas

  • We consider functions defined on an open cover of a domain.
  • The Čech-de Rham complex is obtained by combining
    • differential operators such as the gradient, curl, and divergence.
    • differences of functions on the overlaps.
  • We endow this double complex with a Hilbert space structure to create the $L^2$ Čech-de Rham complex.

Main findings

  • The $L^2$ Čech-de Rham complex is a closed Hilbert complex and a Fredholm complex.
  • In turn, the Hodge-Laplace problems on the Čech-de Rham complex are well-posed.
  • Depending on the choice of open cover, the Hodge-Laplace problem corresponds to certain coupled problems, including:
    • (1D-1D) elastically attached strings.
    • (3D-3D) multi-porosity flow systems.
    • (1D-3D) flow around wells in the subsurface and arteries in biophysical applications.