Lower bounds of Cheeger-Osserman type for the first eigenvalue of then-dimensional fixed membrane problem

A Unified Approach to Estimation of Lowe

A Unified Approach to Estimation of Lower Bounds for the First Eigenvalue of Several Elliptic Boundary Value Problems

✍ Klaus Gürlebeck; Wolfgang Sprössig 📂 Article 📅 1987 🏛 John Wiley and Sons 🌐 English ⚖ 729 KB

## History of the problem While it is relatively easy to get estimations of upper bounds for eigerivalues of elliptic differential operators with the well-known methods of J. W. S. RAYLEIGH and W. RITZ, the estimation of lower bounds is much more complicated. Estimations of lower bounds for eigenv