Astronomical Tests of General Relativity and the Pseudo-Complex Theory

  • Thomas BollerEmail author
  • Andreas Müller
Part of the FIAS Interdisciplinary Science Series book series (FIAS)


Gravitation is very well described by Einstein’s General Relativity. However, several theoretical predictions like the existence of curvature singularities and event horizons are under debate. This motivated to modify the standard theory of gravity. Here, we contrast predictions made by General Relativity with the pseudo-complex field theory proposed recently. Among them we study the gravitational redshift effect, perihelion shift, orbital motion, timing measurements and spectral lines. We consider supermassive black holes as ideal testbeds to test the theoretical predictions in the regime of strong gravity. In particular, we investigate the innermost centers of active galaxies and the Galactic Centre. This involves high-performance astronomical instruments of the next generation. We present feasibility studies with the proposed Athena X-ray experiment and with the upcoming GRAVITY near-infrared instrument to be mounted at the Very Large Telescope.


Black Hole Event Horizon Accretion Disc Very Long Baseline Interferometry Active Galactic Nucleus 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



TB and AM greatly acknowledge extensive scientific discussions with P. Hess, W. Greiner, T. Schönenbach and G. Caspar on the topics presented in this paper. TB is much obliged to W. Greiner for his longstanding scientific support. We thank M. Dovciak and J. Svoboda from the Astronomical Institute of the Academy of Science in Prag, Czech Republic, who significantly contributed in writing up Sect. 3.5. TB is greateful to S. Gillessen for intense discussion on the Galactic Center research.


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Copyright information

© Springer International Publishing Switzerland 2013

Authors and Affiliations

  1. 1.Max Planck-Institute for extraterrestrial physicsGarchingGermany
  2. 2.Technische Universiät MünchenExcellence Cluster UniverseGarchingGermany

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