Regensburg 2007 – scientific programme

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EP: Fachverband Extraterrestrische Physik

EP 12: Grundlagenphysik

EP 12.3: Talk

Thursday, March 29, 2007, 12:15–12:30, H46

Local spacetime dynamics and the PIONEER anomaly — •Hans Jörg Fahr and Mark Siewert — Argelander Institut für Astronomie, Univ.Bonn, Auf dem Hügel 71, 53121 Bonn

Propagation of electromagnetic radiation within the heliosphere should be influenced by the dynamics of the local spacetime metric. The latter, however, is an outstanding problem of General Relativity up to now. Assuming that the general Robertson-Walker like expansion of the universe also takes place on heliospheric scales, would lead to a frequency shift of radiosignals communicated between the Pioneer spacecraft and the earth which perfectly explains the observed frequency shift by its magnitude, but not by its sign, i.e a redshift instead of the observed blueshift should result. We investigate some alternatives to the full Robertson-Walker expansion and introduce a local scale function describing the development of the local density contrast with respect to the average cosmic density. This function can be trimmed such that the Pioneer anomaly is explained as a local radiophoton blueshift.