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arXiv · 1510.04990

Gravitational waves from isolated systems: Surprising consequences of a positive cosmological constant

Abhay Ashtekar·Béatrice Bonga·Aruna Kesavan
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Abstract

There is a deep tension between the well-developed theory of gravitational waves from isolated systems and the presence of a positive cosmological constant $Λ$, however tiny. In particular, even the post-Newtonian quadrupole formula, derived by Einstein in 1918, has not been generalized to include a positive $Λ$. We first explain the principal difficulties and then show that it is possible to overcome them in the weak field limit. These results also provide concrete hints for constructing the $Λ>0$ generalization of the Bondi-Sachs framework for full, non-linear general relativity.

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Abhay Ashtekar, Béatrice Bonga, Aruna Kesavan. 2015-12-31. Gravitational waves from isolated systems: Surprising consequences of a positive cosmological constant. https://doi.org/10.1103/physrevlett.116.051101

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