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 Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

In this PhD thesis I make use of the "Effective Field Theory of Gravity forExtended Objects" by Goldberger and Rothstein in order to investigate theoriesof gravity and to take a different point of view on the physical informationthat can be extracted from experiments. In the first work I present, I study ascalar-tensor theory of gravity and I address the renormalization of theenergy-momentum tensor for point-like and string-like sources. The second andthird study I report are set in the context of testing gravity. So farexperiments have probed dynamical regimes only up to order (v/c)^5 in thepost-Newtonian expansion, which corresponds to the very first term of theradiative sector in General Relativity. In contrast, by means ofgravitational-wave astronomy, one aims at testing General Relativity up to(v/c)^(12)! It is then relevant to envisage testing frameworks which areappropriate to this strong-field/radiative regime. In the last two chapters ofthis thesis a new such framework is presented. Using the effective field theoryapproach, General Relativity non-linearities are described by Feynman diagramsin which classical gravitons interact with matter sources and among themselves.Tagging the self-interaction vertices of gravitons with parameters it ispossible, for example, to translate the measure of the period decay ofHulse-Taylor pulsar in a constraint on the three-graviton vertex at the 0.1%level; for comparison, LEP constraints on the triple-gauge-boson couplings ofweak interactions are accurate at 3%. With future observations of gravitationalwaves, higher order graviton vertices can in principle be constrained through aFisher matrix analysis.

Effective Field Theory Methods in Gravitational Physics and Tests of Gravity