We introduce in continuum mechanics the concept of a material manifold
. To describe, in the continuum limit, a crystalline solid containing
an arbitrary distribution of dislocations, we endow the material manif
old with a structure a k in to that of a Lie group. Starting with a st
ate function defined on the space of local thermodynamic equilibrium s
tates, we formulate the dynamics of crystalline continua in accordance
with the least action principle, within the framework of general rela
tivity, in terms of a mapping of the space time manifold into the mate
rial manifold. We include in our formulation electromagnetic effects.
(C) Elsevier, Paris.