Optimal estimates from below for Green functions of higher order elliptic operators with variable leading coefficients

  title={Optimal estimates from below for Green functions of higher order elliptic operators with variable leading coefficients},
  author={Hans-Christoph Grunau},
  journal={Archiv der Mathematik},
  • H. Grunau
  • Published 2021
  • Mathematics
  • Archiv der Mathematik
Estimates from above and below by the same positive prototype function for suitably modified Green functions in bounded smooth domains under Dirichlet boundary conditions for elliptic operators L of higher order $$2m\ge 4$$ 2 m ≥ 4 have been shown so far only when the principal part of L is the polyharmonic operator $$(-\Delta )^m$$ ( - Δ ) m . In the present note, it is shown that such kind of result still holds when the Laplacian is replaced by any second order… Expand
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