@article {10.3844/ajassp.2004.248.254, article_type = {journal}, title = {Links between Dynamic Physical Systems and Operator Theory Issues Concerning Energy Balances and Stability}, author = {Sen, M. D.L.}, volume = {1}, year = {2004}, month = {Sep}, pages = {248-254}, doi = {10.3844/ajassp.2004.248.254}, url = {https://thescipub.com/abstract/ajassp.2004.248.254}, abstract = {This study relates the properties of operators with the well- known concepts of positive realness and passivity properties in dynamic systems and their associate transfer functions. Those concepts together with very close related ones are first examined from a physical point of view. Then, they are related to hyper-stability and properties of transfer functions while the hyper-stability theorem is revisited and interpreted. Finally, the above concepts are compared to the mathematical concepts of positivity and closely related ones in operator theory in Hilbert spaces.}, journal = {American Journal of Applied Sciences}, publisher = {Science Publications} }