English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We introduce a systematic way to obtain expressions for computing the amountof fundamental quantities such as helicity and angular momentum contained instatic matter, given its charge and magnetization densities. The method isbased on a scalar product that we put forward, which is invariant under theten-parameter conformal group in three-dimensional Euclidean space. Such groupis obtained as the static restriction (frequency $\omega=0$) of the symmetrygroup of Maxwell equations: The fifteen-parameter conformal group in 3+1Minkowski spacetime. In an exemplary application, we compute the helicity andangular momentum squared stored in a magnetic Hopfion.

A scalar product for computing fundamental quantities in matter