Talk detail

Participant	Zieliñski, Janusz
Institution	Space Research Centre Polish Academy of Sciences - ul. Bartycka 18a - Warsaw - Poland - Poland

Session	SG1	Accepted		Order	Time
Talk	Oral abstract	Title	Torsion of the Earth’s anomalous gravitational field resulting from the finite speed of the gravitational interaction
Co-authors
Abstract	The external gravitational field of the Earth is not axially symmetric but is irregular, described by series of the spherical harmonic functions. In the local inertial coordinate system the field is rotating following the rotation of the Earth. In the Newtonian interpretation the field is rotating stiffly with the Earth but according to the Einstein’s General Relativity interpretation the propagation speed of the gravitation is finite and the gravitational anomalies are propagated in space with the speed of light. Consequently the anomalous field at the altitude h should be twisted by angle á = hù/cg comparing to the ground level (ù - the speed of the Earth’s rotation, cg – speed of the gravitational signal). This effect is difficult to measure because of the decreasing of anomaly values with the distance. However, with the modern techniques like GNSS positioning and gradiometry the torsion could be measured. This effect is different from the known Lense-Thirring effect which depends on the rotation of the whole body and not only on the asymmetric distribution of masses within it.