A quasiharmonic field is a pair $\Cal{F} = [B,E]$ of vector fields satisfying $\operatorname{div} B=0$, $\operatorname{curl} E=0$, and coupled by a distorsion inequality. For a given $\Cal F$, we construct a matrix field $\Cal A=\Cal A[B,E]$ such that ${\Cal A} E=B$. This remark in particular shows that the theory of quasiharmonic fields is equivalent (at least locally) to that of elliptic PDEs. Here we stress some properties of our operator $\Cal A[B,E]$ and find their applications to the study of regularity of solutions to elliptic PDEs, and to some questions of G-convergence.
@article{119326, author = {Claudia Capone}, title = {Quasiharmonic fields and Beltrami operators}, journal = {Commentationes Mathematicae Universitatis Carolinae}, volume = {43}, year = {2002}, pages = {363-377}, zbl = {1069.35024}, mrnumber = {1922134}, language = {en}, url = {http://dml.mathdoc.fr/item/119326} }
Capone, Claudia. Quasiharmonic fields and Beltrami operators. Commentationes Mathematicae Universitatis Carolinae, Tome 43 (2002) pp. 363-377. http://gdmltest.u-ga.fr/item/119326/
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