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arXiv · 1706.07482

Implications of a positive cosmological constant for general relativity

Abhay Ashtekar
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Abstract

Most of the literature on general relativity over the last century assumes that the cosmological constant $\Lambda$ is zero. However, by now independent observations have led to a consensus that the dynamics of the universe is best described by Einstein's equations with a small but positive $\Lambda$. Interestingly, this requires a drastic revision of conceptual frameworks commonly used in general relativity, \emph{no matter how small $\Lambda$ is.} We first explain why, and then summarize the current status of generalizations of these frameworks to include a positive $\Lambda$, focusing on gravitational waves.

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Abhay Ashtekar. 2017-06-22. Implications of a positive cosmological constant for general relativity. https://doi.org/10.1088/1361-6633/aa7bb1

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