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Gravitational Waves from Isolated Systems: Surprising Consequences of a Positive Cosmological Constant
Abhay Ashtekar1, Béatrice Bonga1, Aruna Kesavan1
1Institute for Gravitation and the Cosmos & Physics Department, Penn State, University Park, Pennsylvania 16802, USA.
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 a generalization of Einstein's 1918 quadrupole formula that would allow a positive Λ is not yet available. 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, nonlinear general relativity.
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