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Constraining Gravitational Theories by Observing Magnetic White Dwarfs

Oliver Preuss·Stefan Jordan·Mark P. Haugan·Sami K. Solanki
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Abstract

Under the assumption of a specific nonminimal coupling of torsion to Under the assumption of a specific nonminimal coupling of torsion to electromagnetism, spacetime is birefringent in the presence of a gravitational field leading to depolarization of light emitted from extended astrophysical sources. We use polarimetric data of the magnetic white dwarf RE J0317-853 to set for the very first time constraints on the essential coupling constant for this effect, giving k^2 <22 m^2. electromagnetism, spacetime is birefringent in the presence of a gravitational field leading to depolarization of light emitted from extended astrophysical sources. We use polarimetric data of the magnetic white dwarf RE J0317-853 to set for the very first time constraints on the essential coupling constant for this effect, giving k^2 <22 m^2.

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Oliver Preuss, Stefan Jordan, Mark P. Haugan, Sami K. Solanki. 2004-11-25. Constraining Gravitational Theories by Observing Magnetic White Dwarfs. https://arxiv.org/abs/astro-ph/0411688

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