Objective We propose to use conformal invariants to analyse the asymptotic structure of isolated systems in General Relativity. We will perform a rather complete study of the relation between null and spatial infinity.In particular, we shall prove a conjecture regarding asymptotically simple spacetimes (as defined by R. Penrose): that all asymptotically simple spacetimes are stationary in a neighbourhood of spatial infinity.In the light of this conjecture we shall reassess the role of the asymptotic symmetric group (the so-called BMS group), and shall also explore the time asymmetry of certain absolutely conserved quantities at null infinity (the Newman-Penrose constants).The results of the project are of relevance in the numerical simulation of collisions of black holes, and should eventually lead to the construction of physically realistic models of sources of gravitational waves from which templates for the interferometric detectors can be extracted. Fields of science natural sciencesphysical sciencesrelativistic mechanics Keywords Asymptotics conformal methods global existence null infinity spatial infinity timelike infinity Programme(s) FP6-MOBILITY - Human resources and Mobility in the specific programme for research, technological development and demonstration "Structuring the European Research Area" under the Sixth Framework Programme 2002-2006 Topic(s) MOBILITY-2.1 - Marie Curie Intra-European Fellowships (EIF) Call for proposal FP6-2002-MOBILITY-5 See other projects for this call Funding Scheme EIF - Marie Curie actions-Intra-European Fellowships Coordinator CHANCELLOR, MASTERS AND SCHOLARS OF THE UNIVERSITY OF OXFORD Address United Kingdom See on map EU contribution € 0,00