This contribution presents a general numerical method for computing lower and upper bound of the optimal constant in Friedrichs’ inequality. The standard Rayleigh-Ritz method is used for the lower bound and the method of is employed for the upper bound. Several numerical experiments show applicability and accuracy of this approach.
@article{702727, title = {Guaranteed and fully computable two-sided bounds of Friedrichs' constant}, booktitle = {Programs and Algorithms of Numerical Mathematics}, series = {GDML\_Books}, publisher = {Institute of Mathematics AS CR}, address = {Prague}, year = {2013}, pages = {195-201}, url = {http://dml.mathdoc.fr/item/702727} }
Vejchodský, Tomáš. Guaranteed and fully computable two-sided bounds of Friedrichs’ constant, dans Programs and Algorithms of Numerical Mathematics, GDML_Books, (2013), pp. 195-201. http://gdmltest.u-ga.fr/item/702727/