The classical balance equations of mechanics can be shown to lead to new equations, which are instructive in defective deformable solids. These new equations, though mere identities along the motion, can be viewed as additional balance laws that govern the behaviour of the defects and are known as configurational balance laws. However, these laws can be perceived as independent primary laws, when it is possible to appeal for their derivation to a nonclassical variational approach, which is based on the inverse deformation and inverse-motion. Both the classical and the nonclassical variational approaches are here extended to electromagnetic bodies by introducing the electromagnetic potentials in a Lagrangian (or material) form. These potentials turn out to play a prominent role, but as in the classical electromagnetic theory they are not uniquely defined and gauge conditions and gauge transformations therefore are required. The implications of the gauges are investigated both for the Lagrangian electromagnetic theory and more generally for the equations and other quantities in the electromechanical theory. Possible applications to nonclassical continua are mentioned.
Configurational Forces and Gauge Conditions in Electromagnetic Bodies.
TRIMARCO, CARMINE
2007-01-01
Abstract
The classical balance equations of mechanics can be shown to lead to new equations, which are instructive in defective deformable solids. These new equations, though mere identities along the motion, can be viewed as additional balance laws that govern the behaviour of the defects and are known as configurational balance laws. However, these laws can be perceived as independent primary laws, when it is possible to appeal for their derivation to a nonclassical variational approach, which is based on the inverse deformation and inverse-motion. Both the classical and the nonclassical variational approaches are here extended to electromagnetic bodies by introducing the electromagnetic potentials in a Lagrangian (or material) form. These potentials turn out to play a prominent role, but as in the classical electromagnetic theory they are not uniquely defined and gauge conditions and gauge transformations therefore are required. The implications of the gauges are investigated both for the Lagrangian electromagnetic theory and more generally for the equations and other quantities in the electromechanical theory. Possible applications to nonclassical continua are mentioned.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
