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Instabilities in the nonsymmetric theory of gravitation

Tomas Janssen·Tomislav Prokopec
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Abstract

We consider the linearized nonsymmetric theory of gravitation (NGT) within the background of an expanding universe and near a Schwarzschild metric. We show that the theory always develops instabilities unless the linearized nonsymmetric lagrangian reduces to a particular simple form. This theory contains a gauge invariant kinetic term, a mass term for the antisymmetric metric-field and a coupling with the Ricci curvature scalar. This form cannot be obtained within NGT. Next we discuss NGT beyond linearized level and conjecture that the instabilities are not a relic of the linearization, but are a general feature of the full theory. Finally we show that one cannot add ad-hoc constraints to remove the instabilities as is possible with the instabilities found in NGT by Clayton.

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Tomas Janssen, Tomislav Prokopec. 2006-04-21. Instabilities in the nonsymmetric theory of gravitation. https://doi.org/10.1088/0264-9381%2F23%2F15%2F015

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