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

Linearized gravitational waves in de Sitter space-time are analyzed in detailto obtain guidance for constructing the theory of gravitational radiation inpresence of a positive cosmological constant in full, nonlinear generalrelativity. Specifically: i) In the exact theory, the intrinsic geometry of$\scri$ is often assumed to be conformally flat in order to reduce theasymptotic symmetry group from $\Diff$ to the de Sitter group. Our {resultsshow explicitly} that this condition is physically unreasonable; ii) We obtainexpressions of energy-momentum and angular momentum fluxes carried bygravitational waves in terms of fields defined at $\scrip$; iii) We argue that,although energy of linearized gravitational waves can be arbitrarily negativein general, gravitational waves emitted by physically reasonable sources carrypositive energy; and, finally iv) We demonstrate that the flux formulas reduceto the familiar ones in Minkowski space-time in spite of the fact that thelimit $\Lambda \to 0$ is discontinuous (since, in particular, $\scri$ changesits space-like character to null in the limit).

Asymptotics with a positive cosmological constant: II. Linear fields on de Sitter space-time