On a weighted version of the BBM formula
Giorgio Stefani
TL;DR
The paper develops a weighted extension of the BBM formula, proving pointwise and Γ-convergence for weighted nonlocal energies under mild kernel and weight convergence assumptions. It establishes a robust compactness criterion, a weighted Poincaré inequality, and spectral stability results for the first eigenvalue and eigenfunction relative to the weighted energies. A non-local analogue of the weighted BBM formula is also derived, broadening applicability to weighted and anisotropic interactions. Together, these results provide a variational toolkit for analyzing weighted, nonlocal functionals in Sobolev and BV settings with potential applications to fractional operators and spectral problems.
Abstract
We prove a weighted version of the Bourgain-Brezis-Mironescu (BBM) formula, both in the pointwise and $Γ$-convergence sense, together with a compactness criterion for energy-bounded sequences. The non-negative weights need only be $L^\infty$ convergent to a bounded and uniformly continuous limit. We apply the BBM formula to show a Poincaré-type inequality and the stability of the first eigenvalues relative to the energies. Finally, we discuss a non-local analogue of the weighted BBM formula.
