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 establish a variant of the symmetric quasi linear first order systemgiven by H. Friedrich for the evolution equations of gravitating fluidbodies in General Relativity which can be important to solve realisticproblems. Our version has the advantage of introducing only physicalcharacteristics. We state explicitly the conditions under which the systemis hyperbolic and admits a well posed Cauchy problem.

On H. Friedrich's formulation of the Einstein equations with fluid sources