Quantitative Kröger inequalities for Neumann eigenvalues of convex domains

Dorin Bucur, Andrea Gentile, Antoine Henrot

Refining the sharp upper bounds $\hat{I}{¼}_{k,d}^{\ast }$ obtained by Kröger (1999) for the $k$-th Neumann eigenvalue of a convex domain $\hat{I}\text{c◯}\subset {\mathbb{R}}^d$, we prove the following inequ…